Kinda new to loading cast bullets and really need some advice.
I'm shooting a Colt Cowboy in 45LC and have a serious leading problem. Here's the details:
I slugged the barrel and come up with a groove diameter of .4500". The bullet is a .452" Cast Performance LBT style heat treated 250gr RNFP,
most of which actually measure around .4529 on my micrometer. They are supposedly between 18-21 Brinell hardness. They have a clear dry lube. I'll have to take their
word for it because I can't really detect it although they don't feel rough.
The throats of the chambers are at .454". The forcing cone starts at .455". I'm shooting 6.0 gr of Titegroup for a measured velocity of ~820fps.
FWIW, I also notice sooting on the fired cases, but only at one point, not all the way around.
I don't see any chamber to bore misalignment, and it's depositing only the tiniest amount of lead on the frame above the cylinder gap.
Is this simply a problem of shooting too large a bullet? Wrong hardness? Wrong lube? Wrong speed/pressure?
Could the sooting on one side be because of the relatively large diameter of the throats?
The lead build up after just a few rounds is severe. Any advice from you experts is much appreciated.
Thank you.
