Sapper771 said:
Bds, Have you used any 0.358" diameter lead bullets in your Glock factory barrel? I found I got better results with oversized bullets. BHN is around 12 , lubed with BAC, used WSF powder.
No I haven't but you bring up an interesting point. My experience with lead bullets in Glock barrels is that the smooth/rounded rifling with very gradual start of rifling won't engage the bearing surface of the lead bullets like the conventional square cut land/groove rifling. With typical sized bullets (.356" and .401" respectively) and high enough powder charges, this may result in lead bullets losing grip with the rifling. Larger sized bullets may allow better grip with rifling and sealing of high pressure gas to maintain bullet rotation out the muzzle and accuracy of shot groups (especially with softer 12 BHN bullet).
As I posted previously with barrel pictures, lead bullets in Glock barrels also seem to produce more fouling build up than square cut land/groove rifling barrels. The hard/crusty fouling build up will line along the rifling and could be difficult to remove (old copper bore brush wrapped with copper scrubber strands like Chore boy dipped in Hoppes #9 does a good job of this fouling removal). My concern for checking the factory barrels every 200-300 rounds is to check for build up of this fouling that would reduce the barrel diameter and potentially increase the chamber pressure.
I have tested 20-24 BHN hard cast lead bullets (sized .356" and .401" respectively) in the past in 9mm and 40S&W factory Glock barrels using Bullseye, Clays, Titegroup, WST, W231/HP-38, Universal, HS-6 and WSF but got some extent of leading.
In recent years, I have tested 18 BHN Missouri bullets (sized .356" and .401") and when I first did load development with W231/HP-38, I got leading at high-to-max loads but no leading at start-to-high range load data. Like your larger sized bullets, the softer bullets are probably deforming/obturating better even at lower powder charges to seal with the barrel. Accuracy has been good at start-to-high range load data so the deformed bullet base is probably engaging the smoother Glock rifling sufficiently.
My range sessions often involve 300-1000+ rounds and I prefer to use aftermarket Lone Wolf barrels for many reasons:
1. Regardless of powder charge, the brass cases do not bulge from tighter chambers and makes resizing of spent cases much easier (this seems to extend the case life also as I rarely see split case neck anymore).
2. Accuracy is maintained throughout the range session whereas Glock barrels will gradually decline in accuracy as the fouling build up increases.
3. With typically just the lube residue in the LW barrels after the range session, barrel cleaning is easier and faster.
4. Although 9mm LW barrels have comparable case base support as factory Glock barrels, 40S&W LW barrels have fully supported chambers. For me, this is added insurance for peace of mind for the higher pressure 40S&W.
crestoncowboy said:
I have a couple kkm barrels in 10mm on a 6 inch and unlessi'm using a vice I see no difference, unless you are a very good shooter I doubt you will either. They are easier on brass though
I thought about trying a KKM G22 barrel for improved accuracy as posted by some users.