The M73 Tank Gun

290-62.A.1

The period from 1945-1970 did not represent the figurative finest hour in US small arms design. From the problematic M60, to too little too late M14, to the disastrous initial fielding of the M16, US small arms design during the time seemed to simultaneously reach to far and grasp too little. One family of firearms that was a product of this period of development was a short-action armored fighting vehicle secondary machine gun design, incarnated in the M73 7.62mm and M85 .50 caliber, and later M219 7.62mm types. (EDIT: I don’t really think the M85 should be thrown in there, as it’s a substantially different design, though it shares some features with the M73 and M219. Mea culpa.)

Below is a training film covering the operation and disassembly of the “Machine Gun 7.62mm Tank M73”, hosted at the excellent channel of Jeff Quitney:

The M73, though short, got a reputation as being complex and unreliable. Why is unclear to me, as the gun generally appears to be well-thought-out for a tank MG, with some very desirable features:

1. The barrel can be removed while the gun is mounted behind armor, via the receiver swinging from either the right or the left).

2. Feed can be switched from the left to the right, a good feature to allow the gun to be reloaded easily from different positions in a cramped armored vehicle.

3. As previously mentioned, the receiver is short, reducing the space taken up inside the vehicle by the gun.

4. The weapon is charged via a chain, like a lawnmower. In the confines of a tank, this allows the gunner to charge the weapon without either having to reach all the way over to the gun or, god forbid, getting out from behind armor.

5. Cyclic rate of 450-500. This in theory should reduce wear and ammunition consumption while improving reliability, and is plenty high enough for tank MG duties.

6. Solenoid fired, to allow for a remote trigger. The guns are also provided with a manual back-up trigger.

So why was the M73/M85/M219 family so unreliable and bad? Today they have an almost legendary reputation for being stinkers in the field, but I admit I have no good theories as to why they were so unsuccessful. The fundamental designs seem sound enough, and the unique features they brought to the table really do impress.

Whatever the reason, this family of weapons was eventually replaced. The M73, by the improved but not much better M219, and then eventually by the tank variant of the now ubiquitous M240 machine gun, and the M85 by none other than the very weapon it was originally to replace, the timeless “Ma Deuce” M2 Browning heavy machine gun.



Nathaniel F

Nathaniel is a history enthusiast and firearms hobbyist whose primary interest lies in military small arms technological developments beginning with the smokeless powder era. In addition to contributing to The Firearm Blog, he runs 196,800 Revolutions Per Minute, a blog devoted to modern small arms design and theory. He can be reached via email at nathaniel.f@staff.thefirearmblog.com.


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  • Geoff a well known Skeptic

    I was a 45B20 in 1973. The 73 was a joke which tried to assemble it’s bolt from parts on the fly every time the gun was fired. Build a good weapon and then let the designers put it in the AFV. PLEASE!!!

    • Tracey Leavell

      I was an 1833, an amtracker in the Marine Corps, and I can tell you to M-85 was Horrible!! The biggest problem seemed to be that the linked feed shute had several curves between the turret’s magazine and the weapon. We would always take out several links in the feed shute and wedge a piece of cardboard in back of the turret controls to support the feed shute. We would also lube the feed shute heavily. The weapon was also difficult to charge in the small turret, used different links for the .50 cal ammunition, and was always shot on the high rate of fire. The entire amtracker community was pleased when we went to the new turret that had a M-2 and a MK-19 side by side.
      YAT YAS
      Tracey Leavell

      • gunsandrockets

        Early versions of the M-47 Patton had a co-axial .50 M2.

        From your experience with the new amtrack turret, what do you think of the idea of a tank co-axial .50 HMG, and a Remote Weapon Station controlled MK-19 40mm up top?

        • El Duderino

          As a tanker I’ll take a stab at this (Mr. Leavell can obviously do the same).

          Bigger the coax = bigger the hole in the frontal armor. Less ammo inside the turret. Tanks are designed to use the main gun on just about everything short of light vehicles and troops in the open. .50 is overkill on all of those. With 70 tons to soak up the recoil, the 7.62 coax is an absolute laser out to several hundred yards. I’d rather have the higher rate of fire and 10,000 rounds in the hopper than have a .50 or 20mm.

          M2HB vs. a Mk19 on a tank…go with a Ma Deuce. Can carry way more ammo for long engagements. More versatile. The pillboxes and emplacements that call for the Mk19 in the infantry world are solved quite nicely by a 120mm HEAT round. On an Amtrak…yes, having both is great, they don’t have a big main gun to call on…the Mk19 IS the big main gun.

          The current Abrams TC turret system is just about perfect IMO. Not complex with motors and automated stuff, yet still offers protection.

          • gunsandrockets

            I’ll elaborate why I suggested what I did.

            The Israelis have found the 60mm mortar on the Merkava tank useful since it can hit dead ground. A RWS 40mm AGL could do the same thing.

            The original M-1 design selected the .30 over the .50 coaxial because of the simple math of potential kills per ammo load. But that equation might be different today because of DP explosive rounds like the Raufoss. In any case a modern tank is going to have a .50 caliber and carry ammo for it. The question is whether that invaluable asset is better when it can be loaded and fired under full armor protection.

          • El Duderino

            Good luck getting the bean counters to put long belts of Raufoss in the thousands of Abrams tanks out there. They already spaz out enough with SLAP and treat them like the Holy Hand Grenade.

            I’ve had the chance to shoot Mk19 indirectly. It takes some setting up and knowledge to hit squat. I know the Israelis like their mortars but I don’t see it entering into US doctrine anytime soon.

          • doramin

            The main feature is that the Tank Commander’s .50 can be used from behind armor. Remote-controlled .50’s seem to be the main choice. I’ve been binge-watching the Syrian War YouTube vids. The SAA tankers quickly got rid of their DshK’s because in urban war the TC firing the gun outside the hatch was suicidal. There’s a Russian interview with one “Jalil” where he says as much.

            The modern choice seems to be either a remote-controlled design or a bulky cupola for the Tank Commander to work it.

  • Comrade Misfit

    You could probably write a very thick book titled “The Bad Firearms Designed by Army Ordnance”.

    • iksnilol

      You could write a pretty thin book titled “The Good Firearms Designed By Army Ordnance”.

      • zeprin

        And another titled ‘ John Moses Browning: If It Ain’t Broke…’

  • Raoul Duke

    The M73 was initially designed by a very talented designer, Russell Robinson. Army Ordnance took his concepts and “improved” them to the point that they didn’t function. The worst problem with the system was a springy and yielding locking system that would tear cases apart, requiring brass of a certain hardness to function even marginally.
    Do a little more research on Robinson. He designed and patented some way-out guns, including a shoulder-fired .50-cal belt-fed. No kidding.

    • PK

      I have copies of the few articles and photos about Russel Robinson’s designs, they’re fascinating reading. Truly innovating items, but of a completely different nature than the direction small arms ended up going.

      • PK

        I wish to make it very clear that I intend this offer to remain open indefinitely. In the future, if you come across this offer of Robinson’s articles and photos, please make the subject line clear as to what you’re looking for a copy of and I will respond ASAP.

        These articles and photos are too rare and precious to not have a constant source for them, so if anyone has hosting space, please contact me via the previously listed e-mail address and I will send you the files for hosting. In total, they are slightly under nine megabytes in size.

    • The M73 was more inspired by Robinson’s designs. The patents are held by Richard Colby.

  • Pete Sheppard

    There is a joke that the M219 was so designated because it was 3 times the POS the M73 was…

    • AD_Rtr_OS

      Like a Lotus-40: A Lotus-30 with 10 more design faults.

  • Tom – UK

    Watching this video (in particular the barrel changing aspect of it) made me wonder, has a water cooled machine gun ever been considered for an armoured vehicle? Excluding the period where nearly all machine guns were water cooled.

    To me with my ignorance of operating AFVs it seems like you could have a sealed water system (possibly with radiator) to cool the barrel and allow for intense firing. Weight seems negligable but I can certainly see bulk and armour being affected.

    Can anyone educate me on why it would be a good/bad idea?

    • I believe this was done in some early tanks. However, the issue becomes potential damage to the exposed water jacket. Moreover, it would complicate barrel changes when it did become necessary to do so.

      • The following link has some examples of water-cooled MG in armored vehicle mounts:

        http://derela.republika.pl/weap.htm

        • Tom – UK

          Thank you very much, I thought the train based machine gun had a HUGE water jacket at first haha.

      • doramin

        Of course, they say the water-cooled guns could fire forever as long as the water was topped off.

    • Tom

      IIRC there was talk when the Challenger was being planned about using a modernised Vickers machine gun. Remember that the Challenger had been designed not for the British but the Iranians under the Shah. Not sure if it would of been water cooled or air cooled but I can see some logic to using a tried and true weapon like the Vickers in a vehicle. Though I am not sure in modern combat you are going to need to put out quite the volume of fire to necessitate a Vickers over a more modern design.

      • Tom – UK

        I think it would have been sand cooled 😀

    • doramin

      If I understand my history correctly, the water-cooled guns came into their own in the static trench warfare of WWI. But WWII was mobile infantry warfare, water-jacketed machine guns were out of the question for squad fire-and-maneuver tactics and the MG42, M1919 and Bren ruled the field. The earlier generation served as well, but only in fixed positions.

      I had long thought the water-cooled model could be revived. There must be a high-tech way of making it more compact.

    • Tom Currie

      In two decades on tanks and two more as a civilian training specialist at the Armor School, I cannot recall ever seeing (or hearing of) any tank crew changing a coax barrel other than as part of a drill to demonstrate that it could be done.

      With roughly 3,000 rounds linked together in the coax ammo stowage box, it is certainly possible to overheat a coax machine gun and ‘burn out’ the barrel – but on the few occasions that I saw or knew of where firing that much ammo was necessary, overheating the gun and burning out the barrel was exactly what was done.

  • Mostly Cajun

    My first tank training was with the M48A2C with the Browning M37 (M1919 set up for electric firing. It was as good as Browning’s reputation. However, to swap barrels, you had to unmount the thing and then with the new barrel, set headspace. took lots of time.

    I moved to the M60A1 with the M73 and its follow-on, the M219. Part of the problem is that these were NOT solely recoil-operated. The recoil energy was to be augmented by gas energy trapped between the muzzle of the barrel interacting with the barrel sleeve which was REALLY the part mounted in the turret. If the muzzle to sleeve fit was poor, a common malady, the recoil mechanism was anemic. The ammo belt had to be assisted or it would not feed itself.

    Additionally, the breechblock slid sideways, IMHO an unnatural movement, very susceptible to improper lubrication. There were other weak points. The end result was a gun that seldom made its way through a fifty round engagement without a failure.

    On the other hand, my own experiences with both the M48A2C’s cupola mounted M2 and the M60A1’s cupola-mounted M85, the M85 was superior, mainly because it was easier to load, the ammo supply was a 250-round tray instead of a 50-round coffee mug (and whose bright idea was THAT?) and it could be mounted without having to check headspace.

    I cannot remember ever having a failure to operate on my 85’s, on either high or low fire rates.

    • FWIW: Several successful recoil-operated designs used muzzle cap boosters, including the Browning M1919 series.

      I wonder if some of the issues with the M73 weren’t caused by: the stamped receiver getting twisted out of square during repetitive handling inside the turret; the lack of support for the belt; and misassembly of the feed mechanism by users.

  • ghost

    I wonder how many firearms started off being designed like someone’s life might depend on them?

  • Lance

    The M-73 only worked well when put together by the book and it was very temperamental so it wasn’t solder prof and so many had a bad rap for jamming.

  • James Massman

    Can’t really comment on the M73 or even take issue with assessment of evaluation of M14, but… spent 4 years (’64-’68) as a Marine lugging around an M14, 13 months in Chu Lai, and whether sand or monsoon, it never failed. And I knew if I shot someone, not only that one died, but the one behind him did too. If the SHTF, that’ll be my weapon of choice, not an AR.

      • James Massman

        Can’t sincerely argue my point, as I’ve spent recent years shooting AR platforms, and yes, they can be accurate at distance. In fact, I cobbled together a DPMS lower combined with their parts kit and a Blackthorne Products complete upper (16″ chrome), put it to the test at CMP Match even tho it really wasn’t to specs (Not A2, Not 20″, Not Fixed Stock)… still, 10 rounds prone rapid fire 200 yds. = 93., slow fire = better! Not Anti-AR, Nathaniel, just more pro-M1A.

        • Tom Currie

          The AR is a fun toy — but the M14 was the last battle rifle issued to the US military.

          • James Massman

            And that’s why the M14/M1A choice: Keeping an enemy at 500 yds. and out of assault weapon range is my goal, not CQB…
            2 cents

          • Err, no offense, but what makes you think an AR-15 couldn’t hit you at 500 yards?

            http://looserounds.com/2013/06/10/ar15-at-1000-yards-can-a-rack-grade-ar15-and-m855-make-1000-yard-hits/

          • James Massman

            Sorry, I wasn’t clear… Dead at 500 yds., not Hit at 500 yds. But, I’m only talking my own experience with iron sights. Add a scope, then, well, you get my meaning…

          • Why couldn’t an AR-15 kill someone at 500 yards? It’s certainly lethal at that distance.

          • Tom Currie

            An AR15 has a lot better chance of hitting someone at 500 yards than an M16 (don’t even talk about an M4). The shooter with the AR15 might actually have ammo capable of the shot – whereas the poor GI is almost certainly stuck with standard issue ammo (not the 77gr Mk262).

            It might well be lethal at 500 yards – if you spray enough rounds to accidentally hit someone and that accidental hit happens to be in the head or they simply don’t get any medical treatment. Don’t expect the issue ammo to fragment at its remaining velocity — although it might tumble (since it has a good chance that it is already tumbling before it hits).

            I’ll happily admit that I would not choose to stand in the open and have you shoot at me at 500 yards — but that wasn’t the point in a comparison between the M16 and the M14 now is it? Do you want to take your AR15 in the open at 500 yards against someone with an M1A in the open at 500 yards? The word from the sandbox has consistently been that you shouldn’t even try it.

          • It is a myth that the M4 is not accurate enough to hit targets out to 500m. My own experience backs this up, as does the experience of others.

            Would I take an AR-15 out against an M1A at 500 yards? Yeah, sure, I don’t see why not. I can hit the guy just fine at that distance, and I doubt his marksmanship will be so great after he has a few holes in him. That matchup will mostly come down to who’s better with the gun and who sees the other guy first.

            Contrary to the protestations of the M14 crowd, anyone can go to the gun store, pick up a Colt 6920 and some cheap ammo (M855 if you want to be correct, but I mostly have shot 62gr Brown Bear through mine, which is even less accurate and has a lower MV and ballistic coefficient), and start making hits at 500 yards right away, if their marksmanship skill is up to it.

            The gun can absolutely do that. It may not have the most energy at that distance, but I think people would be surprised at how much energy it does have (comparable to 5.7x28mm at the muzzle, a cartridge that is generally considered to have a 200m effective range). Even with absolutely boring ammunition, it can do the job.

          • The A2-style AR-15 outshoots the M14 at Camp Perry pretty routinely. :/

          • Tom Currie

            Last time I checked, the targets at Camp Perry don’t shoot back.

            The M16 and AR15 are perfectly fine for punching small holes in paper inside 300m (and slightly farther with the right ammo). The measure of a battle rifle is NOT its score on a KD range or the number of rounds a lazy draftee is willing to carry around with him.

          • I dunno, man, the vast majority of nations in the world use 5.56mm or something similar, so it can’t be all that bad.

            And for the record, the AR-15 punches paper waaaayyyy beyond 300m. 🙂

  • gb7

    The M219 embedded link leads to Magnum Knives M219 Power Trooper Linerlock Knife with Black G-10 Onlays…

    • Yes, those are automatically added links. Not something I have control over, unfortunately.

  • gb7

    Check the out other links too

  • Bud Harton

    “problematic M60”?
    having fired well over a half million rounds through M60s, we should probably have a discussion concerning that statement.

      • Bud Harton

        Well, I posted based on my extensive experience as a helicopter crew chief/door gunner for 32 months in Vietnam. You based your statement on……? I suspect your knowledge is based on the M60s that came home from Vietnam after being extensively used for anywhere from five to eight years. WEapons asigned to units in Vietnam stayed with the units during their entire deployment. The units did not rotate home, just the personnel. It would be entirely possible for an M60 assigned to (as an example) the 1st 16th Infantry 1st ID to arrive in Vietnam in the fall of 1965 and remain with the unit (and being sent to the field every day) until the unit itself rotated back to the States in 1970. In other words, by the time it got back to the States, it was a shot out piece of garbage. And in the 1970s, the military budgets had been slashed, there were no repair parts or replacement weapons bought until President Reagan restored the military in the 1980s.

        I have the advantage on you in that i served from 1965-69 on Army active duty and then returned to active duty with the Army in 1987 when i retired as a police chief. I was badly injured in 1997 in a training accident and subsequently retired. At the time, I was an Infantry 1st Sgt and I taught my ‘kids’ all kinds of tricks with the M60 to make it run better and faster.
        As I stated, I base my statement on having fired in excess of 500,000 rounds through an M60 in 32 months of combat flight time.

        • Hi Bud,

          If you look closely at all those pictures, you’ll see that the gas system is wired shut to prevent it from backing out. I feel that’s a reasonable application of the word “problematic”.

          • Bud Harton

            I, and every other person who has ever maintained any type of aircraft, used the same method (call safe tying) to secure every nut and bolt, every chip detector and every drain plug on every component on every aircraft every made.
            By your reason, every aircraft ever made has problematic issues?
            Sorry, but there is a locking washer on that piston plug and the safety wire (it’s .035 in size) is merely redundancy.

            How come you don’t know that?

          • Bud Harton

            I will go you one better one better on your photograph “proof”. Here’s a video clip of me (in the helmet with the stripes on the shielf cover) and my buddy Jim who was flying gunner for me. This is an actual gun fight with NVA troops in late 1967. We routinely fired 4-500 round bursts when we were on a gun run. Notice Jim firing from the right side of the aircraft. Notice anything strange about his M60?

            He’s firing it upside down. All the M60s fired from Huey gunships (B and C models) from the right side (the gunner’s side as opposed to the left which was the crew chief’s side) were mounted from the ceiling with a bungee cord attached so the gun would be fired upside down. That was so the constant stream of shell casings and ammo belt clips would remain inside the aircraft instead of flying out and through the tail rotor.

            So, I beat your problematic (not really) photo proof with a counter argument video. Whacha got now?

          • I appreciate you sharing your experiences here. Having said that, you seem pretty annoyed by an innocuous word choice. You can argue that the M60 is a great gun, and that may be true, but it’s also true that some people did have problems with it.

            For the record, I like the M60. Granted, I am not so fond of it that immediately throw up the internet comment equivalent of “them’s fightin’ words” when I see an adjective I don’t like, but I certainly don’t hate the gun. In fact, I’m downright impressed with the Echo 4 variants and on.

          • M60 faults per Peter Kokalis: Parts like the sear and gas piston could be installed backwards, resulting in failures to function. Some users reported that trigger group could work itself loose or fall off completely. If the weapon was loaded and cocked, this would lead to ‘runaway’ fire. When the gas system was sufficiently fouled, the action might cycle just far enough to feed, but not far enough to re-engage the sear. The bolt lugs were particularly prone to burring during use.

            If the feed cover was closed while the weapon was uncocked, damage to the feed pawls would result. Early feed covers were so flimsy that users could bend them in use. A bent feed cover could drag out the buffer retaining yoke, causing the buffer and recoil spring to exit the receiver.

          • Tom Currie

            Show me a gun that CANNOT be assembled incorrectly if you let idiots “maintain” it or that cannot be loaded incorrectly if you let idiots operate it.

            Perhaps a bit off topic for the M73/M219/M85 that the article was about or the M60 that seems to have drawn more interest — but I would like to point out that the Browning machine guns (M1919, M37, and M2) were adopted between 1919 and 1933. The M2 is still in service today (variants of the 1919 were in service in the US and other countries well into the 1970’s). All these machine guns required the operator to check and adjust the headspace and timing. For the past 20 years the US Army has been constantly working to field a version of the M2 that doesn’t require setting headspace and timing because the process is too complicated for our soldiers to perform correctly (as has been evidenced by frequent catastrophic failures in Iraq and Afghanistan). By all accounts (both public statements and actual statistics) we have the best educated Soldiers who have EVER served in the US military. From the time the Browning machine guns were adopted through the mid- to late-1950’s the majority of enlisted soldiers were ILLITERATE (not just Inner City School Illiterate, but as in never learned to read illiterate) – but THOSE soldiers had no problems maintaining the Browning machine guns. And consider the other countries that successfully fielded Browning machine guns, including third world nations including most of central and South America (from Mexico to Chile), much of sub-Saharan Africa, and nearly every non-Communist country in Asia.

          • True, but some designs make it far more difficult to reassemble them incorrectly. You’ll note that US Ordnance has specifically addressed some of these issues in its current M60 variants.

          • Tom Currie

            I don’t know about the M60 being easy to assemble incorrectly — as I pointed out above apparently today anything that CAN be assembled incorrectly becomes the preferred way to do so. Personally I was a barely 20 y/o private when I arrived in country and within a week I was riding the top of a tank with a 1911 on my hip and an M60 on my lap. For the 1911 I had two days of training in AIT — which was two more days of training than I got for the M60.

            Since the Navy is the only branch still using the M60, I can’t say that I kept up with any of “its current variants” but other than the gas cylinder plug I don’t recall any piece that would not have been instantly obvious to anyone with an IQ above room temperature.

            The so-called faults that Mr Kokalis points out generally require having multiple pieces left over after you finish assembling the gun (which OUGHT to be a pretty clear indication that something is wrong). Yes, a totally untrained operator could open the cover with the bolt forward, which would prevent loading the gun BUT contrary to the claim made above, this would NOT damage the feed pawls or any other part of the gun (unless you had an 800 pound gorilla try to charge the gun after you closed to cover with the bolt forward.

            I suppose that Kokalis’s issue about a badly carbon fouled gun MIGHT be possible after firing a few thousands blanks, but I have never seen or heard of this ever being a problem with live ammo. And even with blanks I strongly suspect it would take several days of failing to clean the gun to develop enough powder fouling for anything to happen.

            Personally I put more faith in first hand accounts of people who actually used the M60 in combat over the analysis of self-styled experts who either never fired the gun or who gained their expertise watching shot out old weapons fired on peacetime training ranges.

          • doramin

            So many and varied weapons mountings on hueys over the course of the war. The minigun seems to be on a moveable mounting rather than fixed forward. I never had it explained but was that the arrangement that the pilot controlled with some kind of joystick and was sighted with that strange, flexible gizmo thingy in front of the windscreen?

          • Bud Harton

            The Huey M21 system consisted of two M134 General Electric minmigun, one each mounted externally along with two 2.75″ aerial rocket pods each containing seven rockets. The miniguns were flexed to 90 degrees straight down and 90 degrees out board. They could fles inboard approximately 12 degrees before the safety interlocke would shut off power to the gun turning incoard. They were fired by the aircraft commander in the left seat (now called pilot in command) using a holographic sight mounted on a joystick. This was the forerunner of the current helmet mounted sight. As the gunner rotated the joystick left or right or roated it down, the guns followed the sight. Each minigun consisted of a drive motor, a feeder-delinker and the gun itself. The drive motor rotated the gun which in turn drew the ammo via a belt from the carfo hold of the aircraft. The feeder-delinker removed the clips from the individual round and dropped it into the next breech. The rotation moved the round forward into the barrel and fired it and then extracted in down and outboard of the aircraft. So, you always had a steady stream of clips coming out from the feeder-delinker and and a second stream of shell casings coming from the gun. The guns were powered by the aircraft electrical system and the guns were throttled down from a normal 6,000 per minute to closer to 2,000 rounds per minute. Ammo was fed into the feeder-deiker opposite of how it was fed into the M60. The ammo was contained in trays in the cargo compart. Two rows of trays containing 3,600 rounds each fed each gun. When firing, the gunner squeezed the trigger and the gun cycled for three seconds and cut off to prevent the barrels from over heating. There was a perceived problem that when the pilot, sitting in the right seat, squeezed off a pair of rockets (normally he only fired one at a time for increased accuracy) the minute drop in electrical power could cause the minis to jam so the two pilots coordinated there firing so one was shooting while the other was aiming the aircraft for the rockets and once lined up, he would pounch off however many he verbalized on the intercom (“Firing two) and then the aircraft commander would resume firing.

            Both the crew chief and doorgunner normally fired on their own, that is without direction. We normally fired 100% tracer because it was prettier! but actually because we had a much better view of the target area, we could direct the aircraft by guiding the pilots with our machine gun fire. Door gunners also fired forward on the run in and then out and down on the race track turn with the inside gunner firing below the wingman who was inbound hitting the target on our egress and then the roles reversed. What happened when a good well trained was working was that there was alway 1200 rounds headed at the target from the doorgunners, frequently another 4000 rounds from the miniguns and also alternating 17 pound warheads from the 2.75 FFAR rockets. Except when we used “nails” (flechette) or willy-pete (white phosphorus) war heads. The 17 pound point detonating warhead was the equivalent of a 105mm howitzer shell.

          • Tom Currie

            Those long bursts were another reason that Huey gunners, tankers, and 19D’s didn’t have as much trouble with the M60 as some other folks did — like most post-Browning machine guns, the M60 fired from the open bolt, which meant that the way you stopped firing was that releasing the trigger moved the sear into the path of the bolt to stop it from slamming forward. Every time you stopped firing was a significant amount of wear on the bolt and the sear. Idiots firing short bursts could tear up the gun quite quickly — especially idiots who didn’t hold the trigger all the way back and actually had the bolt grazing against the sear on every round!

          • I can’t recall ever having seen a picture of an M240 that was being held together by safety wire.

          • Bud Harton

            I am sorry i stood up for the M60 against your quite surprising lack of information. If you’re remember I also pointed out you were wrong when you claimed that the 7.62mm duplex round was not widely used in Vietnam. You were wrong on that point also.
            And the safety wire thingee you are clinging to? By that criteria, the French Chauchat was a great weapon system because it didn’t use safety wire.
            Your problem is that you are clinging to pictures and things that you have heard or seen. Then when someone with actual experience points out that you are wrong, you become offended.

          • I didn’t ask for your apology and thanked you for your contributions. I was very interested to learn about the belted duplex ammunition and have thanked you for that; thank you, again.

            Now, since these are your personal experiences and the M60 is a gun of which you are personally fond, you are taking issue with my use of the adjective “problematic”. I feel the use of that word is warranted, even if the M60’s issues were surmountable. Certainly, the weapon has a reputation for being problematic. Beyond this, I don’t feel it’s useful for the two of us to argue about it, since you will be arguing from experience and I will not.

            It appears to me as thought you’ve painted me in your mind as an M60 hater or as looking down on the M60 because of my use of the word “problematic”. I don’t think this is fair to me. The safety wire repair on the M60 is an example of a problem the weapon had in service. Naturally, this doesn’t preclude other systems – such as UH-1 helicopters – from having problems, either, but we do not see similar fixes present with anywhere near the frequency for weapons like the M240. Neither does saying the M60 had this issue preclude other weapons from being problematic in other ways – to suggest what I’ve said is tantamount to arguing the Chauchat was a perfect weapon is more than a bit silly. Of course other weapons can have flaws; but the safety wire appearing so often is direct evidence of a problem the M60 exhibited that had to be fixed.

            So the M60 is problematic. The word choice is appropriate. It may not be a bad weapon, but I never said it was. It may be your favorite weapon, and that status may be well-earned by the excellent service the weapon gave you. But I do not think this means I cannot use the word “problematic” to describe the weapon as a whole.

            Cheers!

          • Tom Currie

            Wired shut to prevent idiots from setting it up to try to get a higher rate of fire. Of course, doing that also ensured that those same idiots wouldn’t ever clean the gas cylinder plug — which pretty much ensured that the gun wouldn’t work long.

            The more significant issue demonstrated in most of those pictures is tangled belts of filthy ammo.

        • doramin

          There’s nothing like the voice of experience. I too, have read that the M60 acquired it’s worst reputation in the seventies and eighties because the guns in service then were worn out. I wonder when they stopped manufacturing them?

        • Kevin Harron

          Hi Bud.

          Just thinking about something in general. I’m not going to discount firsthand door-gunner experience. I’m glad you found it to be an effective weapon for you while you served. I actually think that the M-60 gets a bit of a worse rap than it should. But do you think that your experience moving along at helicopter cruising speed above the jungle would be significantly different from the GIs and Marines down in the jungle? In a helo doing sustained fire with airflow around the gun versus down in the mud with all the jungle crud or dust during the dry season gumming things up during a firefight?

    • CommonSense23

      M60s are extremely problematic if you treat them like GPMG, instead of a LMG like they should be. Same thing as a MK48 vs a 240.

      • iksnilol

        I don’t really know about the M60. Some say it was a problematic POS while others say it was amazing. Same thing applies to all weapons I guess.

        • Zebra Dun

          Do the PM and keep the ammo clean and inside a box before you use it and it will not let you down.
          Wearing the belted ammo around your body was the one event that caused failures.
          Changing the barrels and dropping the receiver into the dirt propped up on it’s bi pod was the other.
          There are lemons and dogs even amongst firearms and when you get one it sucks.

        • CommonSense23

          Right the people who say is was awesome, typically had new ones, and used them a light machine guns. People who complain about them typically had ones that were shot out and using them in a position that doesn’t enhance their strength, as a GPMG.

        • JSmath

          In my experience, the only problem people have with the M60 is that it weighs a lot for a personal small arm.

          • iksnilol

            Eh, all portable MGs are heavy. The lightest one in a “full-power” cartridge is probably the PKM. Though there are lighter ones in intermedia cartridges. Stuff like the CETME Ameli and the KAC Stoner.

    • iksnilol

      The following is just a joke:

      Man, you must have missed a lot. I mean, half a million.

    • Tom Currie

      The problems of the M60 were mostly that the gun had a hard time feeding and firing twigs and leaves. As an 11E, I didn’t have the luxury of a five man team just to carry and operate one M60. So my M60 had one 300 round belt when I was off the tank or one 750 round belt when I was riding topside. Either way, the ammo was protected, NOT looped over my shoulders Pancho Villa style — and my M60 _always_ fired 100%. Meanwhile my 11B neighbors did seem to have more troubles with their M60s. Depending on the unit, near as I could see, the load actually connected to the gun varied from about 10 rounds to what was probably a 100 round belt that couldn’t be fired because it was wrapped around the gunner (and that wouldn’t fire even if he lived long enough to unwrap it because it was full of mud, twigs, and leaves picked up along the way).

    • n0truscotsman

      That word is an understatement IF anything.

      The M60 is a mediocre weapon on its very best day, and IMO, took the entire sound concept/theory behind the MG42 and system of optics and tripod and reinvented a inferior, worse working, wheel.

      Compared to its direct contemporary, the PKM, it was no contest. The PKM still to this day is a tough nut to crack and was better in every other machine gun attribute than the M60.

  • Will

    As a tank crew member, Germany 1964-1967, we used both the M-73 and M-85 on M-60 Main Battle Tanks.
    As a loader I was responsible for the M-73 Coax machine gun. It worked as advertised. Why? Because I was a fanatic about weapons maintenance. I took care of my tanks weaponry and it did what it was designed to do…WORK!! Simple as that!
    Later as a tank commander (TC) and section leader I had the M-85 as my weapon in the TC cupolas. Did it work? Yep! Any problems that were weapon related? Nope! Loved the fact that I didn’t have to mess with head space and timing gauges any longer.
    As I said earlier; I maintained the weaponry and it functioned as advertised. I imparted that mantra to the entire tank section and it proved itself time and again.

  • Cannoneer No. 4

    For the information of the NTMF’s on this thread, a coaxial machinegun was a very important antipersonnel weapon for a tanker, critical in keeping enemy dismounts, RPG gunners, and satchel charge flingers away from your tanks. If your coax doesn’t work right on Tank Table VIII, you are going to have a bad year.

    I HATED the 219! By 1979 the 219’s were so worn out even fanatic couldn’t keep them running.

    • gunsandrockets

      I read that the tanker community argued forcefully for twin co-axial .50 HMG armament during the M-1 tank design phase.

      • Tom Currie

        There has always been a faction within Armor Branch who support the idea of a .50 cal coax. The two arguments for this are that: 1) the space inside the turret would allow a larger amount of ammo than is possible in the cupola or any RWS; and 2) a .50 cal coax would enable the gunner to engage trucks and scout vehicles without having to expend a main gun round. Frequently the suggestion for a .50 cal coax is combined with the suggestion to have a 7.62mm commander’s weapon for use against dismounted troops (traditional coax targets) because with 7.62 there would be room for enough ammo to be useful.

        The arguments against a .50 cal coax have already been presented here.

  • gunsandrockets

    It’s only fair to remember that during that 1945-70 period also saw the fielding of 57mm, 75mm, and 106mm RCL guns, and 40mm grenade launchers. Definite bright spots and ground breaking small arms weapon systems.

  • Dennis Hixson

    Never saw the M73, the M219 was Crap, we were lucky it fire 3 rounds before it stop. I was all ways on the charging Handel! Now the M240 sang! I remember the first time we fired it, I was standing by the charging Handel it never fail us. And the M85 rock and roll too! The only problem I can see with it, it had to be loaded upside down.

  • iksnilol

    Looks like a failed version of the NSV. I know, they aren’t related at all but the cord “charging handle” made me think of the NSV immedately.

  • Phillip Cooper

    I’d always wondered about the wierd flash supressor on the .50 in the M60 tanks, now I know why…

  • AD_Rtr_OS

    Why was it a “stinker”?
    Perhaps for the same reason that the M16 initially encountered so many problems:
    Powder that was incompatible to the design?
    Save a dime here, cost a life there.

  • Tom Currie

    The author’s comments suggest that he is a historical researcher but has never served on any armored vehicle – much less any M48- or M60-series tank equipped with the M73.

    Comments, 1,3,5 & 6 are correct. Comments 2 & 4 however demonstrate his unfamiliarity with armored vehicles. The feed is NEVER switched once the weapon is on a vehicle — the entire mounting and feeding system is designed around feeding the gun from one direction. The ability to change feed direction is useful to the government so that the same weapon could be used on different kinds of vehicles, but that “feature” is useless to the crew of any vehicle. The charging chain is not really any better than the rigid charging handle of the M37 machine gun that the M73 replaced. And it is the tank loader (NOT gunner) who charged the M73 (both for loading and for immediate action in the event of a stoppage).

    Nathaniel scratches his head and asks “So why was the M73/M85/M219 family so unreliable and bad?” Apparently he doesn’t realize that the only purpose of these weapons is to fire. The M73 was a marvel of mechanical ingenuity, but it simply did not work (despite all the great features Nathaniel mentions).

    So, what really was wrong with the M73 and the M219 — the Army never quite figured that out (as demonstrated by the fact that the M219 had exactly the same problems as the M73 it replaced); but tank crews and ASI C5 Master Gunners had plenty of opinions.

    ONE problem of both the M73 and M219 was that the feed mechanism would not reliably PULL ammunition from the stowage box mounted on the turret wall. Apparently it never dawned on the Ordinance Corps testers that this gun was being used in peacetime. In war, the ammo box is full (thousands of rounds), bringing the level of the ammo belt up about even with the gun. In peacetime, you never got more than 300 rounds — not quite two layers of ammo in the very bottom of the ammo box, with the gun having to pull ammo up about two feet. Many crews discovered that they could build up a platform inside the ammo box so that the 200-300 rounds of ammo were at the top of the box instead of the bottom — this did not solve the problems of this gun, but it did help A LOT.

    ANOTHER problem of both the M73 and M219 was that the gun simply jammed frequently even when the feeding problem was mostly handled. We never were able to determine exactly why these guns jammed but my own pet theory had to do with uneven heating and expansion of the different metals used in the mechanism. The M73 and M219 had all the simplicity of a Chinese copy of a Swiss watch. One thing crews found was that (once the feeding issue was handled) the gun would fire just fine cold — and it would continue to fire as it heated up — but if you stopped firing for more than just a few minutes (but not long enough for the gun to fully cool) then started again the gun would usually jam quite quickly. Both the location of the gun and the required “Immediate Action” procedures prevented crews from trying to diagnose the exact nature of the stoppage, but there was no doubt among any experienced tanker that something made these guns jam much too often to be acceptable.

    Nathaniel lumped the M85 in with the M73 and M219, but the M85 was a completely different animal. It was an awkward beast in many ways but those were mostly issues with how the Army manged to stuff it into the limited space in a tank cupola (in some vehicles it was actually mounted upside-down!). The M85 worked quite well as a machine gun, but was still unloved by most tankers due to a variety of reasons unrelated to the gun or its performance.

    First, the M85 was a .50 cal machine gun that did not use the same ammo as the rest of the .50 cal machine guns in the Army. Well, actually it fired the same rounds, but they had to be linked with a completely different link from those used in the M2 (Browning) machine gun. The M85 used ammo with an M15 link where the gun pushed the round forward through the link (much like the M13 links on NATO 7.62mm machine guns) instead of pulling the round out the back of the link as the M2 did. At least in the early years of the M85, you could expect to receive the wrong ammo at least a quarter of the time you received ammo. (Later on, in tank battalions, the few vehicles that had M2 machine guns faced the reverse of this problem).

    The M85 had two selectable rates of fire — Low rate was around 500 rpm, high rate nearly twice that — you were only supposed to use high rate to engage aircraft by simply firing steadily into the air hoping the aircraft would fly into the stream of fire (which was effectively useless due to the small amount of ammo available in the Cupola). The M85 fired from the open bolt. Low rate of fire (which was how you always used the gun) was achieved by a mechanism that caught and held the bolt to the rear then released it a fraction of a second later. This mechanism was contained in the backplate of the machine gun – the bolt would come to the rear – hit a stud on the front of the backplate which would cause a drum to turn winding up a spring – while the drum was turned a mechanism held the bolt to the rear – then when the spring unwound and returned the drum to its rest position, that released the bolt letting it go forward to strip and fire the next round. Surprisingly this Rube Goldberg contraption actually worked — at least as long as the rate selector lever was properly locked in place and the timing spring didn’t break.

    Like the M73 & M219, the M85 used a chain instead of a charging handle. Like the M73 and M219, the M85 also had a manual trigger in case the electrical solenoid failed. BUT unlike the M73 and M219, you couldn’t actually reach the manual trigger on the M85, so firing it manually was accomplished by pulling a handle on the end of a chain — yes, an chain and handle that were identical to the chain and handle used to charge the gun except that the charging handle had a black plastic coating and the manual trigger handle had a red plastic coating — of course they were out of sight from the shooter’s position and hanging side by side (if not tangled together).

    So, bottom line: The M73 and M219 were hated because they would not shoot reliably. The M85 did shoot reliably but it did introduce a number of headaches that some people found bothersome.

    • Cannoneer No. 4

      Tell us about the M60A1 cupola and the M105D Articulated Telescope, Uncle Tom.

    • You’re right that I probably was not right to lump the M85 in. It was designed by AAI, I think.

  • You’re right that there is wire on it, but it’s not clear what it’s holding on, if anything. Could be for a sling, for example.

    • Tom Currie

      By your highly knowledgeable (smirk) standards, the simple presence of safety wire anywhere in the vicinity of any weapon means that wire was used to “repair” the weapon and proves that the weapon design is faulty.

      • So, what would you say to Peter Kokalis, then?

  • John W Faulconbridge

    I have to agree with the folks who are defending the M73 (and M219). You neeed to replace the drive spring before (or immediately after) a gunnery cycle but if you took care of the gun it would take care of you. M85 was also a good gun. switching back to the M2 wasn’t done because it was a bad gun, it was due to the redesign of the TC station.

    • Tom Currie

      You might want to consider replacing BOTH drive springs — not that this would really help either of those pieces of crap, but at least it would make the comment more believable.

      As for the return from the M85 to the M2, that was NOT due to the redesign of the CWS — after all, a new CWS could have been designed for ANY weapon. The major reasons the Army dropped the M85 were financial. The gun itself cost more than the M2 and maintaining two incompatible kinds of .50cal machine gun ammunition in the supply system was a significant cost and had repeatedly proved to be a problem for the logistics system. When the M85 was first adopted, the Army’s intent was to use it as a test bed for a new .50 cal machine gun family that some hoped would replace the “obsolete” M2 entirely in about a decade. No other NATO or SEATO country showed any interest in such a change and no flexible mount version was ever fielded. Although the M85 worked well enough, it never achieved the popularity of the Ma Deuce and eventually the Army realized it was time to return to the proven workhorse heavy machine gun.

  • You know, ribbing the other gentleman aside, dickering over whether a piece of wire on an M240 is holding some essential bits on or not doesn’t change the fact that the M60 did apparently need it.

    And it doesn’t change the fact that many people found the weapon to be problematic. All I’m doing here is defending the use of that adjective.

    • Tom Currie

      Well, from someone who has used the M60 in combat to someone who has never even actually seen one other than in photos, I will simply tell you that the gun did NOT need safety wire or any other modifications to function properly.

      And yes, there were some people with IQs below room temperature who could not figure out how to put bullets in the top, pull the thingie on the bottom, and make those bullets come out the front.

      • Come again? I’ve never seen an M60? How do you figure?

        It’s not exactly correct to suggest that no one who’s used the M60 thinks it’s problematic, is it? Even Bud suggested that this was a common impression among those who served with the gun in the 1970s and ’80s.

        What is most interesting to me is how my use of one adjective has catalyzed such a response as this. I have people outright insulting my experience despite not having any idea what my experience has been. It’s not like I made any extended assessment of the M60, I just called it “problematic”. Is this really an appropriate response?

  • Dennis Hixson

    Sorry Tom your info is not true, I’m a tank crewmember, I’m 5’9″ never had any problem that you mention on the M60A2, I crew the M60A1, M60A2 and the M60A3

    • Tom Currie

      I’m also 5’9″ — the only time I was on an A Deuce was for part of ANCOC — all I can tell you is that with the TC’s platform set all the way up when I stood on it, my eye level was even with the top of the cupola with no chance to see over the sight (although I could look around it if I leaned to the side). But if I sat on the Loader’s seat, and closed the loader’s hatch, I had to bend forward to not hit my head on the inside of the hatch. (And for anyone who has never seen the inside of an A2, the loader HAS TO be sitting if the hatch is closed because there is nowhere to stand except directly behind the breech).

      Whoever designed that turret never heard of the word “ergonomics.”

      • Dennis Hixson

        When and where were you on the A2? I was in katterbach Germany 1/37 armor, we got our A2 middle to late 77

      • Dennis Hixson

        Yes the loader had to set to load the 152 mm gun and stand to load the missile, what’s was wrong about that? You said the only time you were on the M60A2 was in ANCOC? So you really didn’t crew them Like I did, I was on them for 3 years and you A month? Some of your info is right and some not right.

  • You’ve made it very clear that this has really gotten under your skin. That certainly wasn’t my intention.