5.7x28mm Alternative Bullet Weights?

[guru_I_aint]

SO, does anyone know if .223 Remington bullets could be seated into the 28mm cartridge that the P90 uses? I ask because I love the idea of a wicked fireball of a carbine cartridge (read, I don't want a 9mm or .45 ACP carbine). Now, I love the PS90. The thought of a bullpup carbine for a home defense gun is not a new thought by any means but the problem for me, is that the heaviest bullet fired out of the PS90 is only 55 grains. This is fine if it can pierce armor or if it is loaded to it absolute highest velocity but alas, no such round exists for us civilians commercially.

Thus, the question exists, what is the heaviest bullet I can seat into the cartridge that will still fit and reliably feed from the unique magazine that the PS90 uses? I'm thinking it's somewhere in the 60 grain range. Ya ya, it's only 5 grains heavier but, if I'm going to handload, and I can use the heaviest expanding bullets, without messing with the powder capacity or cartridge OAL, I might as well.

If anyone thinks I could get away with a 68 grain BTHP maybe with less powder overall capacity, then please let me know because I would love to be able to load those bulllets into the PS90.

[JimBianchi]

I read here a while ago folks were doing it with 223 55grn.

I have no idea if it is safe at that size or larger.

Why don't you load up some 75grn scream'n meanies lets us knw how it goes.:whistling:

Before you pull the trigger, set up the video camera please......

[guru_I_aint]

Ya and maybe I'll just crunch that powder down as far as it'll go and end up with 100k PSI's and lose some fingers or eyebrows.:rofl:

[Jim Watson]

Could be. Check out the long thread on THR about the Five seveN kaBoom with a froggy reload. Delayed blowback actions are not the place for ballistic experiments.

[JadeRaven]

I believe elite ammunition produces a round available to the public that is of the armor piercing weight and velocity.

[guru_I_aint]

Ya, I found them while researching this dilema of mine. Their rounds are very impressive and unfortunately I've found that this round is extremely fussy. One reload page I found showed a 300 fps increase in velocity with the addition of .1 grains of powder. YA, .1 as in 1/10th! This was measured in the PS90 so the barrel length probably contributed but still. Oh well, from what I've seen, this is a round best left to the experts and I've come across too many mangled hunks of steel and polymer that used to constitute the making of a firearm that dealt with trashy loads from this round and like I said before, I like my fingers and facial hair too much.