308 barrel length v velocity

[rifleshooter]

Hi,

I chopped up a 308 rifle and posted results here: http://rifleshooter.com/2014/12/308-...ty-28-to-16-5/

[Suvorov]

Thanks for the post. Particular interest to me as I contemplate the worth in rebarelling my M1A Socom with a 18 inch Criteria barrel.

If I am reading your graphs correctly, the .308 from a 16.5 inch barrel does not go subsonic until beyond 1000 yards?

[rifleshooter]

Thanks for the post. Particular interest to me as I contemplate the worth in rebarelling my M1A Socom with a 18 inch Criteria barrel.

If I am reading your graphs correctly, the .308 from a 16.5 inch barrel does not go subsonic until beyond 1000 yards?

I would run the velocity with a bullet in a ballistic app. IIRC, last time I looked the 168 and 175 from my 16.5" gun both went subsonic at 800ish. The short barrels drop like a rock downrange- the reason you will never see a bunch of F TR rifles with 16" tubes.