.223 Subsonic twist rate?

[libertyman777]

Originally Posted by LouBoyd

Hart offers a 6" twist barrel. That's the fastest I know of from any manufacturer. Sierra makes 90 grain Matchkings which should give fair wind and drop performance. I would expect that combination to work subsonic though I haven't tried it.

I'm curious though why you'd choose a subsonic 223 Rem over a subsonic 300 whisper. I would expect the performace to be inferior in every respect except maybe for having less recoil. The 223 case has way too much chamber volume to give high expansion ratio and low velocity dispersion. A 221 Fireball would be better, but still more case capacity than optimum.

Hey Lou,

I'm not choosing it over .300 Whisper, I"m including it along with .308 for use with my .30 caliber can (when I buy it). I plan on threading every barrel that I buy for my Savage that is .30 and under. I know that subsonic .223 will not be as quiet as it could be out of a dedicated .223 can and most of the time, I'll be shooting supersonic with the can in place but I was hoping that I could buy a barrel in a twist rate that would allow good performance either way.

I didn't understand part of your answer

Originally Posted by LouBoyd

The 223 case has way too much chamber volume to give high expansion ratio and low velocity dispersion. A 221 Fireball would be better, but still more case capacity than optimum.

. Could you elaborate?

Thanks,

Paul