[320pf]

Kurtz,

If you want to put together the fastest barrel that you can use a 3 or 4 groove barrel or better yet a Polygonal barrel with a 1:10 to 1:12 twist. You do not want to put too much of the powder energy into twisting the bullet like a standard 1:8 300 whisper barrel.

I have been doing a bit or research on Polygonal barrels. David Tubbs one of the top high power shooters uses a polygonal barrel. They are suppose to be very accurate and produce the highest velocities. They also do not foul as easily. Pac-Nor offers polygonal barrels if you are interested. Another source for a polygonal barrel is Schneider Rifle Barrels. This is who Tubbs uses.

I am pretty convinced that a 20-inch polygonal barrel is the way to go to get max. velocities out of an AR.

I am very interested in how the whisper xl turns out that you and Pug are experimenting with. Let me know how it works out.


"you wanna hear something funny, the 16" bolt gun shoots sub-sonic loads about 100 fps faster than the 24" gun with a given charge..."

I can believe that. In subsonic loads the gas pressure drops off to the point that the extra 8-inches add enough friction that it actually slows the bullet down. I bet that there is a lot less report with the 24-inch barrel than the 16-inch barrel (sans suppressor for the comparison)

thanks

320pf