Barrel leading in KKM 10mm Glock 20 Barrel

[Dschuttig]

hello all,

Trying to figure out why my new KKM barrel in 10mm is leading like crazy! Shooting 9grs Power pistol behind Mp hollow point, 160ish grain water quenched wheel weights. Lubed with LBT soft blue. Bore slugs right at .400. I've tried sizing .400, .401 and .402. Using m die with appropriate plug and checked to make sure no squeezing of bullet. Seems no matter what I do it leads like crazy. Same load (same bullets) in my Blackhawk shoots fine with zero lead, ever.

Any thoughts?

[khmer6]

Maybe the tight chamber /throat could be shaving or staging it down. Never had an issue with the lee 175 in stock and wolf barrels for the 20 and 29. Tumble lubed.

[DougGuy]

KKM makes really pretty barrels but they don't have much throat in them at all. I have had good results with throating them .4025" to give about .150" worth of freebore in front of the chamber before the leade in to the rifling. Could be your throat is just small enough to be shaving the boolits as they leave the case mouth and subsequent boolits push it into the bore.