Hi Rob, thanks for the advice. Got good accuracy with this barrel before with 20 thou jump. Tried it once with a jam, and the gun did not like it. Kept chasing the lands as they wore out, and eventually the 140 Berger could not get that close to the lands anymore, without falling out of the case.
At that time, 140 gn projectiles were the heaviest and longest available for 6.5 CM. Since then the Hornady 147 ELD-M and 153 A-tip and the Berger 156 gn became available, so i can now chase the lands again with these longer bullets. [It is an 8 twist barrel, hope it will stabilize these long heavy bullets.]
I deep cleaned the barrel over multiple days, and a lot of carbon came out. Amazing what is left inside a “clean” barrel when you put a bore scope in there. There was defintely a carbon ring in the chamber as well, but the entire barrel had severe carbon fouling. Too much RL-17 perhaps. Such a dirty powder.
So really hoping the extreme carbon removal cured the erratic speed issue... and that the barrel can become the basis for an accurate hunting rifle.
This is what a dummy round looks like when loaded to a 20 thou jump with the 147 ELDM... Bordering on the ridiculous, but what do i have to lose....
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