India’s new Modern Submachine Carbine (MSMC) and 5.56x30mm Ammunition

During the past few years India’s Armaments Research and Development Establishment (ARDE) have been developing an interesting Personal Defense Weapon (PDW) called the Modern Submachine Carbine (MSMC).

Modern Submachine Carbine
Modern Submachine Carbine

The firearm chambers a round developed in India called the 5.56x30mm. This round is sometimes referred to as the “5.56x30mm INSAS” after the first gun to chambered the round, the INSAS Carbine.

5.56x30mm MARS rifle cartridge
5.56x30mm MARS

Those of you who follow the industry closely may recall that Colt developed a round named the 5.56x30mm MARS during the 90’s as part of their now defunct Mini Assault Rifle project. I imagine the INSAS cartridge is very similar. The Colt patent describes the MARS cartridge:

The MARS cartridge is designed as part of the weapon system and exploits the high energy densities of modern ball powders. It for the first time uses magnum pistol type powders burned at rifle pressures to achieve high rifle velocities in a short rifle barrel. It uses a fast ball powder to achieve 2600 ft/sec with a 55 gr full metal jacket projectile in only an 11 inch barrel.

The MARS cartridge/rifle was able to achieve similar ballistics as a ultra-short barreled 5.56x45mm NATO rifle (I use the term rifle loosely, sub-carbine is more correct), but with less muzzle flash, noise and weight. The Indians went with the 5.56x30mm over the 5.56x45mm for these exact same reasons as Colt.

Out of a 11″ barrel, the MARS Rifle was able to push a 55 grain bullet at 2600 fps, generating 825 ft/lbs of muzzle energy. For comparison, according to Wikipedia, the original Colt Commando (11″ barreled sub-carbine) could push a bullet (presumably a 55 grain M193 Ball) at 2750 fps.

Colt M4 Commando (current model)

While the 5.56x30mm has advantages over a pistol cartridge such as the 9mm NATO, to wit, less weight and kevlar vest penetration, it has in my opinion one fatal flaw. 5.56mm bullets were never designed to operate at such low velocities. While 2650 fp/s may seem fast, that is at the muzzle, not 200 meters downrange where the target is situated.

A graph I generated. Numbers are estimates for illustration only.

Col. Martin L. Fackler, MD famously did a study which determined that a 5.56mm bullet (M193 and M855) would fragment only slightly ,or not at all, when hitting flesh below the speed of 2500 fps. Low fragmentation results in a .22″ sized hole in the target – less damaging that a .38″ (9mm) or .45″ hole.

Col. Martin L. Fackler, MD 5.56mm
Col. Martin L. Fackler, MD results

It will be interesting to see how this new sub-carbine and perform in real life, and what official nickname the cartridge is given. I think 5.56mm India or 5.56mm Short should are much better named than 5.56x30mm INSAS.

Hat Tip: 8-AK Defense News and Ammoland

Tag: 5.56×30

Steve Johnson

Founder and Dictator-In-Chief of TFB. A passionate gun owner, a shooting enthusiast and totally tacti-uncool. Favorite first date location: any gun range. Steve can be contacted here.


  • Freiheit

    It seems to me that a submachine gun isn’t really designed to work well at 200 meters no matter what the ammo or muzzle velocity is. How does it do clearing rooms and fragging watermelons??

  • Kris

    I think the issue is, however, that the 5.56 does its deed by by fragmentation. That’s how the wound is generated.

    As the “bullet board” shows, you gotta be above 2500 fps to reliably generate fragmentation. Based on the estimated velocity chart, that is no more than about 25 yards.

    While true that a PDW is a short range weapon, I’d like it to be reliably beyond 25 yards.

  • Whatever

    If their goal was a meaningful round based on the 5.56x45mm cartridge out of a shorter barrelled gun, I would have gone for a larger diameter bullet in a case of the same length, something like the 6.5mm TCU. A larger bore should let a similar weight bullet reach a similar velocity from a shorter barrel.

    If I was going to go through the trouble of making a new submachine gun to fire a new cartridge, I’d pick a better cartridge, like the 9×25 Dillon (115gr @ 1800 fps from a 6″ barrel). I thought sub-machine guns were supposed to be for engagements of a hundred yards or less.

    • Whatever, I agree

  • Matt Groom

    Ten mill gives me a thrill,
    better than some .22 pill.
    Disagree you might, but still
    these shoes may be tough to fill.
    Better designs? There are nil.
    I think .40 fits the bill,
    when you have to take that hill
    you need a little more than will.
    When hostiles break your chill,
    you need something that can kill.

    • Matt, ha ha, nice

  • jody

    been lurking here for a year. first post.

    how is this new indian round any different than the 6×35 round developed for the knight’s armanent PDW? seems like almost the same thing, only worse.'s_Armament_Company_PDW

    • jody, good to have you posting!

      I agree with you. Same concept, but I think that a heavier 6mm bullet would be better.

  • Vitor

    Well, the Knight 6mm isnt really that heavier, 62 grains.

  • komrad

    I’d take a P90 over that little thing any day. Probably a bit heavier but the bullpup design and longer barrel would give it a little more versatility. And it looks like that thing doesnt have anywhere near the 50 round capacity of the P90.

  • DanKnyphausen

    Just a little food for thought.. think about procurement versus expected use. A 1.7″ long round (the 5.56mm MARS and, I’m guessing, this one as well) could find its way ino the envelope of replacing the following:

    -Sub-Machine Gun
    -Sub-Carbine/Micro Carbine (those 10″ and smaller barreled M4-like things that’re becoming all the craze)
    -Personal Defence Weapon (in its truest meaning, for REMF’s and vehicle crews)

    With just one or two purpose-made weapons. That’s four weapons, of at minimum two calibers (say 9x19mm and 5.56 NATO), replaced by one weapon that could possibly use the same projectile (a 55gr bullet if the Idians do switch over to 5.56 NATO and something like the SS109). Those purpose-made weapons could be:

    -A “Machine Carbine” with all the performance of a rifle round at close quarters (fragmentation, wounding ability, shock ability, pain and suffering, debilitation, and armour penetration) and out to 250-300m (typical combat range, ask the Germans and why they made the 8mm Kurtz round). This would be for special operations use, MOUT use by infantry or mechanized forces, COIN/CT/Anti-Terror/High-Risk Breach for SWAT units, in a weapon about the same size as, say, something the size of an HK33KA3 with a retractable stock – a “carbine-like” weapon, that’s “full sized” for this round. I’m thinking a good 13″ to 13.5″ barrel or so, with a folding or collapseable stock that goes all the way to the receiver, to keep it very compact and lightweight for long distance missions (and to save weigt for more ammo at the same total weight package). That should keep it still smaller than an M4 and the two/2.5 extra inches of barrel should bring long distance (100+m) performance up to at least par with the M4 Carbine. The chart up there omits the M4’s performance (14.5″ barrel), but it’s a good guess that it’s about in between the MARS and the M16, towards the lower end. Capacity, ideally, would be 40-50 rounds per magazine.. as much as 60 if it can be done efficiently (think weight, size, existing mag pouch dimensions, etc.)

    -A “Personal Defence Weapon” with the performance of a rifle round at very close ranges (0-50m). This would be something like the MSMC above, or like the H&K MP7. This would replace handguns, SMG’s and existing “crew personal weapons” for non-infantry personnel and be designed for *defencive* use. That is, put plenty of rounds down range while moving away from the engagement. If the enemy is ambushing your convoy, they’re almost at knife-and-bayonet range as it is. You don’t need a weapon that can kiss the fly on their head at 200m, you need one that can hit the torso of a man-sized target at just a few dozen feet. The MP7 comes with “spoon-tip” rounds, that seem to be plenty legal (Hague convention – the Bundesheer is issuing the MP7 now, and they are, I believe, signatories of it), and in a larger (.223″ vs .183″ or 5.7mm vs 4.6mm) round, plenty lethal. In this weapon, hits count. If you have five troops returning fire with five of these PDWs and one on a mounted weapon, that’s six things throwing full-auto lead in a nice blanket – high hit probability, and good enough to cause either debilitating wounds or death on enough targets to make escape possible. For India worrying about Pakistan, this makes great sense.

    By replacing SMG’s, Sub-Cars, almost all Handguns (General/Staff Officers could be issued a handgun in this same caliber, the round is only 0.10″ longer than the P90 round) and PDW’s, you save on Training requirements (time and money). By acquiring two weapons instead of (at least) four, you save acquisition costs. By switching to one caliber instead of (at least) two, you save ammunition costs. By using the same types of projectiles, you save on acquiring new machines to make bullets.. the list goes on. It’s incredibly cost effective, in theory, and it simplifies weapon training for those that aren’t expected to do much fighting, AND gives the potential for extending these benefits to SWAT-type units.. the postives can potentially outweigh the negatives, if the system is implemented correctly and with enough forethought.. an if the politicians can stay out of the mess.

  • DanKnyphausen

    I should note that these two weapons would *compliment* standard Assault Rifles and such in the mainstream military (front line) environment, NOT replace them. As good as this midrange round may be, you still need the ability to land a good amount of debilitating and/or lethal hits at the 300+ meter range.
    Possibly, for Mechanized/Heliborne/Light Infantry troops, the “Machine Carbine” could be restricted to two Troopers in six (whichever two would, ordinarily, either need their hands free the most, or would be most likely to sweep buildings, backed up by a man with a full-power S.A.W. like an Ultimax 100), the rest would have purely standard weapons.
    For REMF troops, and the “Personal Defence Weapon” it would be the exact opposite. All but, say, two Troopers in six, the remaining two with full power carbines and light optics (3.5x or so). Again, the idea being that they aren’t there to fight, jut to be able to protect themselves if they’re attacked, and be able to withdraw. The two sets of boots with carbines being the best two shots in the group already, and having a tool that takes maximum advantage of that. Even if the ratio is 5:1, it’d still be a huge benefit.

  • prettypete

    No offense, but I’ve heard that the PDW, machine carbine and carbine replacing the pistol or that the pistol has, heretofore, become redundant oftentimes before. However, the pistol though far from ideal in the battlefield and especially in its bigger bore variants, has always staged a comeback.

  • prettypete

    Interesting and well thought out analyses, Dany. And great track on the pistol issue, that they should share the same ammo as the PDW.

  • Jere

    A change in the bullet’s construction (Thinner jacket etc…) could allow it to perform, or fragment, with-in it’s velocity range.
    Why compare it to a bullet designed for higher velocities?

  • Jason B.

    Why does everyone try to either replace one thing at a time or kill 2 birds with one stone. I say dump the whole system! Get rid of 9mm 5.56×45 and 7.62×51
    Replace all three with two rounds. One a PDW/pistol/sub carbine round two a dedicated rifle round that spits the difference between the 7.62 and 5.56 both in energy (1800-2000ftlbs) and diameter (6.5mm)

    i had a concept for a telescoped 77grain 5.56/5.7x38mm PDW round that would have the same base dimensions of a 9mm(for ease of transition). the bullet would be made primarily of two materials aluminum in front + lead in the rear (making it likely to yaw) with a thin copper jacket(to insure frag even at slower velocities) and a titanium tip to help penetrate body armor.
    the projectile would be a double ogive (double pointed) the rear facing lead side looking much like .22lr hollow point pointing backward(a lot like a boattail but longer) and the front being much pointier like a 5.45.

    the round would be optimized for a 16in barrel 2500fps and 1068ftlbs(assuming the right powder is used). Out of a 8 inch barrel I calculate a muzzle velocity/energy around 2095fps/750ftlb

    external ballistics are tough to predict because of the round’s COG (causing it to be slightly less stable) however it is easily overcome by the round’s shape and sectional density (giving it a high BC around .4+) at 400yards the round would actually have more energy than a 5.56NATO when both are fired from a 16 inch barrel. At 600 yards it officially goes subsonic and turns toward it’s base(and becomes a Hollow point)

    i predict the terminal effects would essentially be the equivalent of a 31grain 5.7 and 45grain .22mag hitting roughly the same spot at the exact same time.(fragmenting into two main pieces and causing two wound cavities that in places open up into one large one.

    • Rob

      This is absolutely absurd. You’re joking about all of the above, right?

  • pepe romo

    They should call it the Akuzi.