11-13-2019, 02:13 AM
Stevil Wrote:yeah that velocity is well under what you should be getting, I get 3000fps with my 20in HB, 90gr TNT/31gr of 8208.
You might want to check your data. 3000 fps with a 90 tnt is 24 inch barrel velocity.
You might be running a bit warm for your barrel.