Reflex
I've GAINED 250fps (in a 30-06) by having the barrel shortened 1" at the chamber end, and recutting the chamber properly.
A chamber cast before "surgury" showed the throat was .3125 in diameter, the "post surgury" cast is .3085 in diameter. If the throat diameter is at bullet size the bullet acts as a plug to the gases, if the diameter is above bullet size the gases can blow past the bullet until it is in the lands.
Stop spinning your wheels, and get a chamber cast done and measured.
