Yeah I've always used brass, your not going to hurt chromoly or stainless steel with brass, I've accidentally grabbed the wrong cleaning rod and jammed a 26 cal jag into one of my 22-250s it was hard as hell to get out, but my buddy run the bore scope up in it and you couldn't even tell it happened.
It's copper after all, as I type KG-12 is working miracles, I haven't used it in this rifle, never had so much copper fouling before, it's either excessive speed of the loads or V-Max is made from different material, which I doubt.
Yep, primers show a lot of pressure, looks like they got print of the bolt surface...
From 100 yard zero it took 3.5 MOA to get to 300 yards... Its about 3300.0 ft/s, this is fast but I'm not shooting match barrel... Its Remington factory varmint barrel.
Hey bud if you have some RE10X load up a couple for shits and grins it may give you the best of both, speed and accuracy, like I said both of my 22-250s love it. But I sounds like it shooting pretty damn good.
RL-10, hmmm maybe, never had any experience with it, RL-15 the lowest one I tried from Alliant, but H-335 was performing very good before, going to repeat myself: I didn't like how it was getting in every part of the powder dispenser.