Thread: Shortened barrel impact on factory ammo FPS

Greetings,
Velocity loss when shortening a barrel is highly variable. For my .308 with AR2206H I allow 20fps per inch from the Hodgdon 24 inch barrel data down to my 20 inch barrel using the same cases. For slower powders like AR2208 it is more. Chronographing your load (or factory loads) in your barrel is the only way to be sure. Generally the slower the powder, the bigger the case and the shorter the barrel the more velocity you will loose.
GPM.