I have seen a move towards armor piercing rounds in SMG's recently(H&K MP7 PDW and FN P90 f.eks., as well as the recent sweedish PDW), but I have also read a lot of articles by gunwriters questioning the stoppingpower of the 4.6mm HK round, and the 5.7mm FN round, because of low energy/low diameter(The FN p90-round has about as energy from the P90 as a 9mm+p from a pistol. The H&K round even less).
The problem with the .223 compact carbines(I'm not thinking of the M4, but the even shorter barreled supercompact XM-8, or HK G36C) is lack of velocity, and as a result the bullets don't fragment, and this hurts stoppingpower(ice-pick like performance). The problem with the 9mm, .40s&W and .45acp guns, is the lack of armor piercing abillity, and lack of effective range due to more rainbow-like trajectory.
This got me thinking. What if you put a somewhat longer .355 diameter spitzer-bullet in .357 SIG brass, with a steel or tungsten tip, and a small circular cavity around the steel/tungsten tip, like a conventional hollowpoint, so that it would both penetrate soft body-armor, and expand if hitting an un-armored enemy. Also, in the longer barrel of an SMG, the high pressure of the .357 sig would result in a larger gain in velocity(Just as f.eks. the .357 magnum, which practically doubles it's energy from revolver to carbine because of the longer barrel), and thereby more energy than any conventional SMG, or even the fine-caliber HK and FN guns. Also, a longer spitzer-bullet will maybe result in better ballistics, and better sectional density. At least, that's the theory.
So, what I'm wondering about is if this, in theory, would be plausible for use in either a slightly modified(rechambered and new magazine) conventional SMG like the H&K UMP or in a theoretical SMG designet around this round, and with a Calico or PP-90M1-like helical magazine. A helical magazine would give the gun even more ammo per magazine than the FN P90. I am not thinking of this round for use in pistols, only in SMG's and PDW's.
So, give me input people. Inform me of anything I have overseen, anything that speaks against this solution, or anything you think could improve upon this. Also, if you think this is a good solution, I want to hear it too.
Christian.
The problem with the .223 compact carbines(I'm not thinking of the M4, but the even shorter barreled supercompact XM-8, or HK G36C) is lack of velocity, and as a result the bullets don't fragment, and this hurts stoppingpower(ice-pick like performance). The problem with the 9mm, .40s&W and .45acp guns, is the lack of armor piercing abillity, and lack of effective range due to more rainbow-like trajectory.
This got me thinking. What if you put a somewhat longer .355 diameter spitzer-bullet in .357 SIG brass, with a steel or tungsten tip, and a small circular cavity around the steel/tungsten tip, like a conventional hollowpoint, so that it would both penetrate soft body-armor, and expand if hitting an un-armored enemy. Also, in the longer barrel of an SMG, the high pressure of the .357 sig would result in a larger gain in velocity(Just as f.eks. the .357 magnum, which practically doubles it's energy from revolver to carbine because of the longer barrel), and thereby more energy than any conventional SMG, or even the fine-caliber HK and FN guns. Also, a longer spitzer-bullet will maybe result in better ballistics, and better sectional density. At least, that's the theory.
So, what I'm wondering about is if this, in theory, would be plausible for use in either a slightly modified(rechambered and new magazine) conventional SMG like the H&K UMP or in a theoretical SMG designet around this round, and with a Calico or PP-90M1-like helical magazine. A helical magazine would give the gun even more ammo per magazine than the FN P90. I am not thinking of this round for use in pistols, only in SMG's and PDW's.
So, give me input people. Inform me of anything I have overseen, anything that speaks against this solution, or anything you think could improve upon this. Also, if you think this is a good solution, I want to hear it too.
Christian.
Last edited: