5.56mm ammunition for an 8.5 inch barrel?

[BCannell]

I need some suggestions for 5.56mm ammunition that will reliably fragment at ranges up to 100 yards out of an 8.5 inch barrel with 1:7 twist. Any ideas?

 

[Mike Irwin]

Only thing I can suggest is Winchester hollow point varmint ammo. Stuff seems to almost come apart in mid air.

 

[IZinterrogator]

That's what I was thinking, the 45-gr. stuff. You aren't going to hit the magic 2700 FPS where the bullet fragments out of a 8.5" barrel. The 45-gr. JHPs are the only ones that will come out of that barrel with a decent (although probably not 2700 FPS) speed. And that 1/7 twist will probably rip them apart, sending multiple bullet fragments downrange at high speed, but with totally degraded accuracy. Best of luck.

 

[BCannell]

Aren't there bullets that will fragment at lower velocities?

I figure that there must be something that produces a decent wound, or else no one would purchase sub-compact 5.56mm rifles like the G36C, SIG 552, Galil MAR and MTAR-21.

 

[Mike Irwin]

The Winchester ammo is the only ammo I know of that might fit your requirements.

Bullet design can be very fussy.

If you design a bullet designed to fragment at very low velocities, chances are it won't stand up to higher velocities very well, or the stress of firing.

And, I'd say that the bullets for just about every .223 round you'll find on the market are designed to provide adequate expansion at velocities quite a bit higher than what you're going to be getting out of your rifle.

Why?

Because there just aren't that many 8.5" barreled .223s in civilian hands.