I have a 26in bartlein 1-7.5 twist chambered in 6 Creed on a impact 737. It was a great shooter with around 0.3 moa groups and SD's around 4 for at 2945 fps for about 600 round. Since then I have a big increases in velocity with about every 80 - 100 rounds. It will just anywhere from 35 to 40 fps and my SD's have slowly moved up to around 11. Now my velocities are up around 3080 fps and if i try to change my load at all i get pressure signs even though i am near a minimum charge of powder. Also I have to rezero every couple of weeks. My groups are still around 0.5 moa at 100 yards. I have tried different brass and powder and primers with no change. I have close to 1600 rounds on this barrel. I am wondering if I should pull it off and get a new barrel. My buddy has the same spec barrel as me on a impact and his will shoot lights out with what ever he throws in it. If someone has a recommendation for something else please let me know.
Unusual velocity changes.
- Thread starter PB6creed
- Start date
1600 rounds is about where I would expect the barrel to drop off. But the velocity numbers don’t normally go up at end of life. The other things like pressure and you saying you are at minimum loads. Have you checked you powder thrower against a different scale?
I'd scope the bore to see if you have a carbon ring or other buildup. Also see how the throat is looking.
Cleaning regimen? I would be borescoping for carbon ring and setting barrel back to steel or minimal fouling and checking again.
