When I ran 40 rds of Remington factory ammo through my never-fired Sendero 300WM a couple weeks ago, cleaning produced some copper but that was about it.
Yesterday I ran my first batch of 14 handloads thru it (69.8-72.0gr Re22 under 200gr Accubonds). The first 8 shots were ok...groups of 2 shots either touching/same hole with a third opening it up to about 1" (as likely me as the
. The last two groups, however (the higher charges) were terrible...2.5" and 3.5". I assumed the gun didn't like the charges as the shots felt good when I took them.
When I cleaned the gun, I was mystified to have the first patches come out black as coal, like from my muzzleloader. It took a few to get down to the copper, which also seemed increased over last shoot.
I've never heard Re22 as being such a dirty, dirty powder...everyone seems to like it, but now I'm suspicious that after 8 shots the groups opened up due to excessive fouling. Cleaning every 6 shots seems ridiculous in a centerfire.
Is this normal with this powder? Something to do with the factory tube?