Comments on: .50 BMG necked down to .22 http://www.thefirearmblog.com/blog/2009/09/08/50-bmg-necked-down-to-22/ Firearms not Politics Sun, 21 Mar 2010 05:46:29 +0000 http://wordpress.org/?v=2.9.2 hourly 1 By: John Waters http://www.thefirearmblog.com/blog/2009/09/08/50-bmg-necked-down-to-22/#comment-27464 John Waters Thu, 25 Feb 2010 02:00:42 +0000 http://www.thefirearmblog.com/blog/?p=7656#comment-27464 I am dreaming of looooong barrels and deep draughts of slow burning powder.... Anyone have any Hodgdon 570 laying around, still? I am dreaming of looooong barrels and deep draughts of slow burning powder…. Anyone have any Hodgdon 570 laying around, still?

]]> By: Bryan S. http://www.thefirearmblog.com/blog/2009/09/08/50-bmg-necked-down-to-22/#comment-27416 Bryan S. Wed, 24 Feb 2010 04:27:02 +0000 http://www.thefirearmblog.com/blog/?p=7656#comment-27416 Wonder how it compares to the .950? http://en.wikipedia.org/wiki/.950_JDJ Wonder how it compares to the .950?

http://en.wikipedia.org/wiki/.950_JDJ

]]> By: Steve http://www.thefirearmblog.com/blog/2009/09/08/50-bmg-necked-down-to-22/#comment-17982 Steve Thu, 12 Nov 2009 03:14:36 +0000 http://www.thefirearmblog.com/blog/?p=7656#comment-17982 Redchrome, yep, they are low pressure rounds so that is the limiting factor. Redchrome, yep, they are low pressure rounds so that is the limiting factor.

]]> By: Redchrome http://www.thefirearmblog.com/blog/2009/09/08/50-bmg-necked-down-to-22/#comment-17981 Redchrome Thu, 12 Nov 2009 03:12:15 +0000 http://www.thefirearmblog.com/blog/?p=7656#comment-17981 Actually, now that I think of it, I wonder how fast you could go with an APFSDS round from a 12ga. shell? Fundamentally it's not that different in dimensions from a modern tank cannon. Limiting factor is that shotguns aren't built for high pressures. Actually, now that I think of it, I wonder how fast you could go with an APFSDS round from a 12ga. shell? Fundamentally it’s not that different in dimensions from a modern tank cannon. Limiting factor is that shotguns aren’t built for high pressures.

]]> By: Steve http://www.thefirearmblog.com/blog/2009/09/08/50-bmg-necked-down-to-22/#comment-17980 Steve Thu, 12 Nov 2009 02:48:33 +0000 http://www.thefirearmblog.com/blog/?p=7656#comment-17980 Redchrome, very interesting. Redchrome, very interesting.

]]> By: Redchrome http://www.thefirearmblog.com/blog/2009/09/08/50-bmg-necked-down-to-22/#comment-17978 Redchrome Thu, 12 Nov 2009 02:47:03 +0000 http://www.thefirearmblog.com/blog/?p=7656#comment-17978 Some years ago I saw some gimmick rounds where a guy had necked a .50 BMG case down to .17. He did one as a full-length case; and another as an extreme example of a 'short, fat magnum' where the case was maybe an inch and a quarter long.. it had barely any sidewall to it. Must have taken a lot of patience and time on a lathe to thin the walls down enough to be able to do that. I've heard of people making up .378 Weatherby-.22 wildcats, and I heard they tended to blow up... there's just too much powder being rammed down too small a hole, and the throat erodes away almost immediately. (they do supposedly get 6000fps tho). I don't know what the propigation speed of nitrocellulose powder is, or what the practical limits of bullet speed are; but as some anecdotal baselines, I do believe that some tank cannon projectiles (presumably High Velocity Armor Piercing Fin Stabilized Discarding Sabot) exceed 6000 fps. This is noteworthy when you consider how short a tank cannon barrel is, compared to a rifle barrel. In terms of length to caliber ratio, they're like long-barreled pistols. :) Another anecdotal value is the handloads for .30 cal sabots with 55-grain bullets. http://www.eabco.com/Reports/report04.html Basically, it seems that you can't get much faster than about 5000fps. They claim 5300fps for a 55-grain bullet in the .30 sabot from a .300 Weatherby; but I'd like to see some independent confirmation. Larger bores are much more efficient at transmitting powder burn into velocity. This is mostly because the increased area at the projectile base allows more pressure to be expended on the bullet. A side-by-side comparison of .44 Magnum vs. high-pressure .45 Colt loads will demonstrate this. http://www.foxwebdesigns.com/Area51/JLSixGun/articles/gunnotes.html For really high velocities, I'd try to get ahold of some of the .50 BMG sabots the military/Olin has for SLAP rounds, and stuff them with comparatively light bullets into a .50 McMillan Fat Mac case with a monstrously long barrel. It would be barely man-portable, and throat erosion would be a problem (like it is with any of these massively overbore rounds); but you could probably go pretty fast with it. http://www.thehighroad.org/showthread.php?t=139053 Still, as is pointed out above, we're starting to hit the limits of how fast we can burn the powder. The highest-velocity guns are the size of buildings, and burn hydrogen to build the pressure to rupture a diaphragm and drive very small things at exceedingly high speeds (orbital velocities) to see what happens when you throw debris at a spacecraft or the like. I know NASA has one. Some years ago I saw some gimmick rounds where a guy had necked a .50 BMG case down to .17. He did one as a full-length case; and another as an extreme example of a ’short, fat magnum’ where the case was maybe an inch and a quarter long.. it had barely any sidewall to it. Must have taken a lot of patience and time on a lathe to thin the walls down enough to be able to do that.

I’ve heard of people making up .378 Weatherby-.22 wildcats, and I heard they tended to blow up… there’s just too much powder being rammed down too small a hole, and the throat erodes away almost immediately. (they do supposedly get 6000fps tho).

I don’t know what the propigation speed of nitrocellulose powder is, or what the practical limits of bullet speed are; but as some anecdotal baselines, I do believe that some tank cannon projectiles (presumably High Velocity Armor Piercing Fin Stabilized Discarding Sabot) exceed 6000 fps. This is noteworthy when you consider how short a tank cannon barrel is, compared to a rifle barrel. In terms of length to caliber ratio, they’re like long-barreled pistols. :)

Another anecdotal value is the handloads for .30 cal sabots with 55-grain bullets.

http://www.eabco.com/Reports/report04.html

Basically, it seems that you can’t get much faster than about 5000fps. They claim 5300fps for a 55-grain bullet in the .30 sabot from a .300 Weatherby; but I’d like to see some independent confirmation.

Larger bores are much more efficient at transmitting powder burn into velocity. This is mostly because the increased area at the projectile base allows more pressure to be expended on the bullet. A side-by-side comparison of .44 Magnum vs. high-pressure .45 Colt loads will demonstrate this.
http://www.foxwebdesigns.com/Area51/JLSixGun/articles/gunnotes.html

For really high velocities, I’d try to get ahold of some of the .50 BMG sabots the military/Olin has for SLAP rounds, and stuff them with comparatively light bullets into a .50 McMillan Fat Mac case with a monstrously long barrel. It would be barely man-portable, and throat erosion would be a problem (like it is with any of these massively overbore rounds); but you could probably go pretty fast with it.
http://www.thehighroad.org/showthread.php?t=139053

Still, as is pointed out above, we’re starting to hit the limits of how fast we can burn the powder. The highest-velocity guns are the size of buildings, and burn hydrogen to build the pressure to rupture a diaphragm and drive very small things at exceedingly high speeds (orbital velocities) to see what happens when you throw debris at a spacecraft or the like. I know NASA has one.

]]> By: Roper1911 http://www.thefirearmblog.com/blog/2009/09/08/50-bmg-necked-down-to-22/#comment-17909 Roper1911 Wed, 11 Nov 2009 03:08:37 +0000 http://www.thefirearmblog.com/blog/?p=7656#comment-17909 Titanium alloyed with the appropriate metals(tungsten carbide, nickle-cobalt) can be harder than steel,[random amateur metallurgist thought coming in 3...2...1...] instead of a titanium bullet, try a cobalt-bismuth alloy bullet (with out using the charts 60 parts Bismuth to 40 parts cobalt sounds good), that way you have ultra high velocity integrity and still retain some mass. make sure to powder the cobalt to about the grain of table salt or it won't dissolve into the bismuth right; that way you don't need a 2750F furnace. Titanium alloyed with the appropriate metals(tungsten carbide, nickle-cobalt) can be harder than steel,[random amateur metallurgist thought coming in 3...2...1...] instead of a titanium bullet, try a cobalt-bismuth alloy bullet (with out using the charts 60 parts Bismuth to 40 parts cobalt sounds good), that way you have ultra high velocity integrity and still retain some mass. make sure to powder the cobalt to about the grain of table salt or it won’t dissolve into the bismuth right; that way you don’t need a 2750F furnace.

]]> By: Steve http://www.thefirearmblog.com/blog/2009/09/08/50-bmg-necked-down-to-22/#comment-17842 Steve Mon, 09 Nov 2009 21:56:23 +0000 http://www.thefirearmblog.com/blog/?p=7656#comment-17842 Roper1911, interesting, but a Titanium alloy would be harder, right? Roper1911, interesting, but a Titanium alloy would be harder, right?

]]> By: Roper1911 http://www.thefirearmblog.com/blog/2009/09/08/50-bmg-necked-down-to-22/#comment-17832 Roper1911 Mon, 09 Nov 2009 16:06:54 +0000 http://www.thefirearmblog.com/blog/?p=7656#comment-17832 Steve, no offense, titanium(Rockwell scale: B70, Method B is use on softer metals) is softer then barrel steel (Rockwell scale: C50, method C is used on harder metals, C50 equals about B100-120) , I'd still suggest a cobalt-steel-tungsten alloy barrel for the thing though, that round would push some PSI... Steve, no offense, titanium(Rockwell scale: B70, Method B is use on softer metals) is softer then barrel steel (Rockwell scale: C50, method C is used on harder metals, C50 equals about B100-120) , I’d still suggest a cobalt-steel-tungsten alloy barrel for the thing though, that round would push some PSI…

]]> By: chris http://www.thefirearmblog.com/blog/2009/09/08/50-bmg-necked-down-to-22/#comment-16422 chris Fri, 16 Oct 2009 22:08:31 +0000 http://www.thefirearmblog.com/blog/?p=7656#comment-16422 if only it would hold together, i'd love to know what fps thats doing lol if only it would hold together, i’d love to know what fps thats doing lol

]]> By: crimson30 http://www.thefirearmblog.com/blog/2009/09/08/50-bmg-necked-down-to-22/#comment-14965 crimson30 Wed, 23 Sep 2009 14:56:04 +0000 http://www.thefirearmblog.com/blog/?p=7656#comment-14965 For those interested in this sort of thing, here's a good thread on the matter: http://www.thefiringline.com/forums/showthread.php?t=311773 For those interested in this sort of thing, here’s a good thread on the matter: http://www.thefiringline.com/forums/showthread.php?t=311773

]]> By: nateF http://www.thefirearmblog.com/blog/2009/09/08/50-bmg-necked-down-to-22/#comment-14618 nateF Thu, 17 Sep 2009 01:10:14 +0000 http://www.thefirearmblog.com/blog/?p=7656#comment-14618 there have been stories of palistinian terrorists using this. they use a discarding sabot, so that the full thing is a plain .50 cartrige, just using a metal tipped plastic round. the plastic would fall off quickly after leaving the barrel, and the powder burns like any normal .50. the bullet does have issues with effectiveness though. the friction of a little piece of metal going that fast will turn it into a drop of molten copper, and when it hits, it is more like what happens with an ap round, burns its way through. there have been stories of palistinian terrorists using this. they use a discarding sabot, so that the full thing is a plain .50 cartrige, just using a metal tipped plastic round. the plastic would fall off quickly after leaving the barrel, and the powder burns like any normal .50. the bullet does have issues with effectiveness though. the friction of a little piece of metal going that fast will turn it into a drop of molten copper, and when it hits, it is more like what happens with an ap round, burns its way through.

]]> By: Mu http://www.thefirearmblog.com/blog/2009/09/08/50-bmg-necked-down-to-22/#comment-14487 Mu Tue, 15 Sep 2009 14:31:33 +0000 http://www.thefirearmblog.com/blog/?p=7656#comment-14487 Hmm, this makes my idea of recreating the German 7.92x99 anti-tank round on a .50BMG case look like a minor task. Hmm, this makes my idea of recreating the German 7.92×99 anti-tank round on a .50BMG case look like a minor task.

]]> By: Caleb http://www.thefirearmblog.com/blog/2009/09/08/50-bmg-necked-down-to-22/#comment-14305 Caleb Fri, 11 Sep 2009 00:12:29 +0000 http://www.thefirearmblog.com/blog/?p=7656#comment-14305 I don't know about you guys, but, I believe this is a great idea. All you would need is a barrel of optimum length to let all of the powder burn. But, if the riflings in the barrel (and the barrel itself) were made out of tungsten-carbide, and, you used monolithic bullets that are of a tough alloy like titanium, this could be pulled off. The only problem would be finding someone dumb enough to shoot it. Well....maybe not... I don’t know about you guys, but,
I believe this is a great idea.
All you would need is a barrel of optimum length to let all of the powder burn.
But, if the riflings in the barrel (and the barrel itself) were made out of tungsten-carbide,
and,
you used monolithic bullets that are of a tough alloy like titanium,
this could be pulled off.
The only problem would be finding someone dumb enough to shoot it.
Well….maybe not…

]]> By: SB_Pete http://www.thefirearmblog.com/blog/2009/09/08/50-bmg-necked-down-to-22/#comment-14263 SB_Pete Thu, 10 Sep 2009 09:02:35 +0000 http://www.thefirearmblog.com/blog/?p=7656#comment-14263 LOL, well, you'd get bragging rights for sure at least. I believe the uninhibited expansion speed of nitro cellulose powders is right about 5000fps though, so you actually wouldn't get much more velocity than a .204 Ruger. Lots of nifty sound and fury though. Perhaps it could be advantageous in propelling some sort of really long solid tungsten dart type projectile out of a 50" bbl? lol. I want one on my bookshelf for sure though ;-) LOL, well, you’d get bragging rights for sure at least. I believe the uninhibited expansion speed of nitro cellulose powders is right about 5000fps though, so you actually wouldn’t get much more velocity than a .204 Ruger. Lots of nifty sound and fury though. Perhaps it could be advantageous in propelling some sort of really long solid tungsten dart type projectile out of a 50″ bbl? lol.

I want one on my bookshelf for sure though ;-)

]]> By: Komrad http://www.thefirearmblog.com/blog/2009/09/08/50-bmg-necked-down-to-22/#comment-14247 Komrad Wed, 09 Sep 2009 21:41:04 +0000 http://www.thefirearmblog.com/blog/?p=7656#comment-14247 Maybe you could do it with some sort of sabot. Maybe you could do it with some sort of sabot.

]]> By: Tim http://www.thefirearmblog.com/blog/2009/09/08/50-bmg-necked-down-to-22/#comment-14214 Tim Wed, 09 Sep 2009 02:04:17 +0000 http://www.thefirearmblog.com/blog/?p=7656#comment-14214 hahaha well, i geuss i have lots to learn, thanks for the info. hahaha well, i geuss i have lots to learn, thanks for the info.

]]> By: Steve http://www.thefirearmblog.com/blog/2009/09/08/50-bmg-necked-down-to-22/#comment-14212 Steve Wed, 09 Sep 2009 02:02:30 +0000 http://www.thefirearmblog.com/blog/?p=7656#comment-14212 Tim, the problem is that the bullet has to be softer than the barrel! And if the barrel is to hard then the rifling cannot be cut accuracy, mean lower accuracy. Firearms technology almost always is about tradeoffs and finding an optimal solution. Tim, the problem is that the bullet has to be softer than the barrel! And if the barrel is to hard then the rifling cannot be cut accuracy, mean lower accuracy.

Firearms technology almost always is about tradeoffs and finding an optimal solution.

]]> By: Tim http://www.thefirearmblog.com/blog/2009/09/08/50-bmg-necked-down-to-22/#comment-14211 Tim Wed, 09 Sep 2009 02:00:34 +0000 http://www.thefirearmblog.com/blog/?p=7656#comment-14211 what about titanium bullets? haha. it would raise the price to somewhere around 50 bucks a round but hey. i'd pay that to shoot it once. what about titanium bullets? haha. it would raise the price to somewhere around 50 bucks a round but hey. i’d pay that to shoot it once.

]]> By: Steve http://www.thefirearmblog.com/blog/2009/09/08/50-bmg-necked-down-to-22/#comment-14200 Steve Wed, 09 Sep 2009 01:29:22 +0000 http://www.thefirearmblog.com/blog/?p=7656#comment-14200 gunslinger, yep, it would need to be rebarreled. The problem is that modern day bullet cannot handle the extreme velocity that such wildcats can produce. There have been many attempts at simular overowered, under sized cartridges. gunslinger, yep, it would need to be rebarreled. The problem is that modern day bullet cannot handle the extreme velocity that such wildcats can produce. There have been many attempts at simular overowered, under sized cartridges.

]]> By: XxleoxX http://www.thefirearmblog.com/blog/2009/09/08/50-bmg-necked-down-to-22/#comment-14189 XxleoxX Tue, 08 Sep 2009 22:57:05 +0000 http://www.thefirearmblog.com/blog/?p=7656#comment-14189 this is the reason i got to TFB :) this is the reason i got to TFB :)

]]> By: Ken http://www.thefirearmblog.com/blog/2009/09/08/50-bmg-necked-down-to-22/#comment-14181 Ken Tue, 08 Sep 2009 21:59:16 +0000 http://www.thefirearmblog.com/blog/?p=7656#comment-14181 10,000 fps? lol... 10,000 fps? lol…

]]> By: Crabula http://www.thefirearmblog.com/blog/2009/09/08/50-bmg-necked-down-to-22/#comment-14171 Crabula Tue, 08 Sep 2009 18:19:47 +0000 http://www.thefirearmblog.com/blog/?p=7656#comment-14171 I would seriously like to know how long the barrell would have to be for all of the gunpowder to combust before the bullet exited. You know, to obtain optimum efficiency without wasting half of the powder-charge after the bullet is half way down range. Definately not a good cantidate for a new sbr cartridge. :) Then again, I can't think of much that this would be a good cantidate for. I would seriously like to know how long the barrell would have to be for all of the gunpowder to combust before the bullet exited. You know, to obtain optimum efficiency without wasting half of the powder-charge after the bullet is half way down range.
Definately not a good cantidate for a new sbr cartridge. :)
Then again, I can’t think of much that this would be a good cantidate for.

]]> By: Paul_In_Houston http://www.thefirearmblog.com/blog/2009/09/08/50-bmg-necked-down-to-22/#comment-14165 Paul_In_Houston Tue, 08 Sep 2009 17:01:10 +0000 http://www.thefirearmblog.com/blog/?p=7656#comment-14165 My memory may be playing tricks on me, but I SWEAR that when I was a kid (more years ago than I like to think) there was a comic book story in which a .50 caliber round necked down to .22 was featured, playing up "hydrostaic shock" as making it so terrible and lethal. Late '50s, I think. (Yeah. What WERE we teaching our kids through the comics back then? :-) - My memory may be playing tricks on me, but I SWEAR that when I was a kid (more years ago than I like to think) there was a comic book story in which a .50 caliber round necked down to .22 was featured, playing up “hydrostaic shock” as making it so terrible and lethal. Late ’50s, I think.

(Yeah. What WERE we teaching our kids through the comics back then? :-)

-

]]> By: dg http://www.thefirearmblog.com/blog/2009/09/08/50-bmg-necked-down-to-22/#comment-14158 dg Tue, 08 Sep 2009 15:43:06 +0000 http://www.thefirearmblog.com/blog/?p=7656#comment-14158 I dont care what it takes someone needs to develop an alloy that would work for this. Practical: heck no, expense:more than 50cal id imagine, but it would be way to cool. Even if they were dummy loads this needs to be done and marketed. As for the name try "22 gladiator" or something with a little more 'cool factor' than Xpress. I dont care what it takes someone needs to develop an alloy that would work for this. Practical: heck no, expense:more than 50cal id imagine, but it would be way to cool. Even if they were dummy loads this needs to be done and marketed. As for the name try “22 gladiator” or something with a little more ‘cool factor’ than Xpress.

]]> By: gunslinger http://www.thefirearmblog.com/blog/2009/09/08/50-bmg-necked-down-to-22/#comment-14150 gunslinger Tue, 08 Sep 2009 14:26:28 +0000 http://www.thefirearmblog.com/blog/?p=7656#comment-14150 But what kind of barrel would you need? because that's a change from .22 to .50 But what kind of barrel would you need? because that’s a change from .22 to .50

]]> By: SpudGun http://www.thefirearmblog.com/blog/2009/09/08/50-bmg-necked-down-to-22/#comment-14141 SpudGun Tue, 08 Sep 2009 13:24:59 +0000 http://www.thefirearmblog.com/blog/?p=7656#comment-14141 We've all thought about doing this, haven't we? If this project ever did become a reality, my biggest problem would be to get all 35 squirrels to line up in a row. I could nail them to a plank, but that kinda defeats the sporting purpose. We’ve all thought about doing this, haven’t we? If this project ever did become a reality, my biggest problem would be to get all 35 squirrels to line up in a row.

I could nail them to a plank, but that kinda defeats the sporting purpose.

]]> By: Steve http://www.thefirearmblog.com/blog/2009/09/08/50-bmg-necked-down-to-22/#comment-14139 Steve Tue, 08 Sep 2009 12:47:28 +0000 http://www.thefirearmblog.com/blog/?p=7656#comment-14139 haha. You just get copper dust shooting out the barrel instead of lead ;) haha. You just get copper dust shooting out the barrel instead of lead ;)

]]> By: Nomen Nescio http://www.thefirearmblog.com/blog/2009/09/08/50-bmg-necked-down-to-22/#comment-14138 Nomen Nescio Tue, 08 Sep 2009 12:45:57 +0000 http://www.thefirearmblog.com/blog/?p=7656#comment-14138 so, solid-copper bullets for when we actually try this for reals? ;-) so, solid-copper bullets for when we actually try this for reals? ;-)

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