Details:
9mm Kimber Custom II (1911 A1)
Barrel slugged 0.355"
Boolits sized 0.356"
Boolits are 15 BHN (using a Lee hardness gage)
120 grain TC
Hi-Tek coated (passed the smash test)
Speed - Unknown, I do not have a chronograph
Expanding the brass using a M Die
Crimped using a factory crimp die
Powder - 3.4 - 3.7 gr. Titegroup
Primer - Federal Small Pistol
Question:
I am having a leading issue. The lead streaks go down the entire barrel with more deposits seeming to be towards the crown. According to the Lyman Cast Bullet Handbook, 3.3 to 3.7 grains of Titegroup can be used safely so I feel the speed is not excessive. I also saw where someone else was having issues using Titegroup with the Hi-Tek coating but I'm not sure his conclusion was accurate. Can someone share his experience with this issue and hopefully what I need to do different to eliminate the leading issue?
Thanks in advance