I have been keeping close eye on throat lengths of my custom 300RUM. I have kept 3 particular bullets as references to use in my stoney point AOL guage. After 300 rounds in this new barrel, I have seen almost no differences to reach the rifling. This is a Kreiger heavy barrel. With two other RUM's I saw some thoat length changes at 300rounds. I never shoot max loads and the gun never gets hot.

I am just shocked. I am going to take to my gunsmith to look at thru his hawkeye to see if all looks good. One difference with this barrel is I only use wipeout to get the copper and fouling out. No more brushes or scrubing.