Possable to put a .358 caliber bullet in a strait case 223?
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FrankenMauser
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The maximum reasonable limit, considering common barrel groove diameters and commonly available bullet diameters, is .338".
Since the .338" bullet diameter is essentially a rifle-cartridge-only affair, that means the case has to be shortened just like .300 Blackout.
The result is along the lines of .338 Spectre.
35 caliber is a bit much. Possible, with a straight-wall cartridge that headspaces on the mouth and neck walls that are thinned to less than 0.009" (too thin for good neck tension, and too thin to resist deformation from lateral pressure with a long bullet seated).
Possible.
But not advisable.
Since the .338" bullet diameter is essentially a rifle-cartridge-only affair, that means the case has to be shortened just like .300 Blackout.
The result is along the lines of .338 Spectre.
35 caliber is a bit much. Possible, with a straight-wall cartridge that headspaces on the mouth and neck walls that are thinned to less than 0.009" (too thin for good neck tension, and too thin to resist deformation from lateral pressure with a long bullet seated).
Possible.
But not advisable.
Theoretically, you could do it, but it would present a number of problems.
First, the cartridge would have to headspace on the case mouth like a 38 Super or 45 ACP. Not a huge problem with short cases, but with longish cartridges it will prove difficult in application. This issue killed the 400 Whelen, 10.15X57mm, and seriously impaired the 35 WSL, 351 WSL, and is one of the reasons why rifles typically use bottlenecked cartridges. Sure, some cartridge developers went ahead anyway, but very few.
Second, the cartridge would have to feed straight into the chamber without any angle. Longish cartridges tend to be difficult to feed. Not as big of a problem with lower pressure cartridges, but a serious issue when you start to develop higher pressure. 120 years ago, they solved the issue by tapering the cartridge, but then you lose the needed case diameter for the .357 bullets. When you consider this, it pretty much eliminates most magazine-fed rifle actions.
First, the cartridge would have to headspace on the case mouth like a 38 Super or 45 ACP. Not a huge problem with short cases, but with longish cartridges it will prove difficult in application. This issue killed the 400 Whelen, 10.15X57mm, and seriously impaired the 35 WSL, 351 WSL, and is one of the reasons why rifles typically use bottlenecked cartridges. Sure, some cartridge developers went ahead anyway, but very few.
Second, the cartridge would have to feed straight into the chamber without any angle. Longish cartridges tend to be difficult to feed. Not as big of a problem with lower pressure cartridges, but a serious issue when you start to develop higher pressure. 120 years ago, they solved the issue by tapering the cartridge, but then you lose the needed case diameter for the .357 bullets. When you consider this, it pretty much eliminates most magazine-fed rifle actions.
I don't know about the .35 and 351 Self Loaders being impaired since they have a rim to headspace on just like the original .38 ACP/Supers.
The largest practical bullet is .338" and the .338-223 Straightwall is exactly that. Having said that, AR15.com for a short time offered a rimless .357 Magnum barrel for AR-15's.
I don't know if pressures are the limiting factor either. Both the 10mm and the .460 Rowland load to some pretty high pressures and they use a taper crimp. The 9x23 Winchester loads to even higher pressures.
I think it's more of a feeding issue in semi-autos. Bottle-neck and taper wall cases simply feed better. Then again, the Coonan seems to have no problem with long, straight .357 Magnums.
The largest practical bullet is .338" and the .338-223 Straightwall is exactly that. Having said that, AR15.com for a short time offered a rimless .357 Magnum barrel for AR-15's.
I don't know if pressures are the limiting factor either. Both the 10mm and the .460 Rowland load to some pretty high pressures and they use a taper crimp. The 9x23 Winchester loads to even higher pressures.
I think it's more of a feeding issue in semi-autos. Bottle-neck and taper wall cases simply feed better. Then again, the Coonan seems to have no problem with long, straight .357 Magnums.
.223 case diameter at the shoulder is .354". .375" at the extractor groove. That doesn't mean you can use a .375" bullet though. Cases usually need a bit of taper to function right. Even the .44 AutoMag, a cartridge originally made from cut down .308 cases, has a wee taper.
.348", maybe. However, like FrankenMauser says, finding common barrels and bullets make a huge difference when you're playing with unusual/weird stuff. .348" bullets can be had without much fuss, but they're 200 grain rifle bullets.
.348", maybe. However, like FrankenMauser says, finding common barrels and bullets make a huge difference when you're playing with unusual/weird stuff. .348" bullets can be had without much fuss, but they're 200 grain rifle bullets.
No. Not unless you have the chamber set for headspacing on the mouth. There is no room for a shoulder. might not even be possible to create a straignt walled case for it as the outside diameter of a .223 case at the shoulder is .358, but the diameter at the base appears to be .377. I don't know if expanding the case to a direct straight line would leave enough room inside that brass, since the outer dimensions will still be only .020 larger, and that's just not enough to fit the thickness of the brass.
Just offhand, I'm sure that someone else has already thought about this, and if it worked, it would have been used extensively by now.
Just offhand, I'm sure that someone else has already thought about this, and if it worked, it would have been used extensively by now.
I've been trying to find some data on case wall thickness, Not case neck thickness, and all I can find id that case necks can run up to .016 in thickness, and no, that's too large to directly fit. You would have to create an oversized chamber for that round, and that's assuming that the body of the case would be thin enough to work.
I'm still going to fall back on the thought that you need to research whether it has been done before. If it was ever successful, that round would have become fairly well known. I think that a 160 grain or so round traveling at 2k or even higher out of a carbine would make a lot of people happy. It sounds like it would be ver effective as a combat round. Heavier bullets would be very effective taken to subsonic loads, maybe.
I'm still going to fall back on the thought that you need to research whether it has been done before. If it was ever successful, that round would have become fairly well known. I think that a 160 grain or so round traveling at 2k or even higher out of a carbine would make a lot of people happy. It sounds like it would be ver effective as a combat round. Heavier bullets would be very effective taken to subsonic loads, maybe.
Here is a fellow that has an ar15 running, shows what he had to do to get it to run.
http://castboolits.gunloads.com/showthread.php?312313-357AR-(Max-Rimless)-AR15
http://castboolits.gunloads.com/showthread.php?312313-357AR-(Max-Rimless)-AR15
He went through a lot more effort than I did but this is a step by step forming process.
http://castboolits.gunloads.com/sho...ss)-from-223-5-56-cases&p=3724676#post3724676
http://castboolits.gunloads.com/sho...ss)-from-223-5-56-cases&p=3724676#post3724676