Here's my recent findings on HBN coated bullets (143 ELDX)... As ya'll probably know by now, my 260 rem is now assembled and I've been breaking the barrel in and trying to find "my load" for it recently (130 rounds now).

My first 100 rounds down the barrel where "naked" bullets... the last time I went to the range I shot a total of 50 rounds (had some fantastic groups with that batch of reloads). I went home after that string and foamed my bore as usual... Even after a 50 shot string and a 24 hour foam treatment, I barely had any blue come out from copper fouling.

Went to the range again this last weekend (I HBN the entire box of bullets) with some other loads to try out.... Shot a total of 30 rounds and with only a couple "good groups"... Went home and foamed the bore as usual for 24 hours.... Ran a patch down the barrel and had a river of blue coming out the end of the barrel!!!! It was as bad as my 270 Savage barrel was....

I don't know why this is happening.... Everything I read about HBN says it should reduce copper fouling, not exaggerate it... Has anybody else experienced this?