Ok. I got a GP 100 38spl/357 mag. I was planning on using a 158g SWC for my primary load. I am wanting to make sure I am understanding this correctly.
For cast lead bullets you want the bullet 0.001 larger than the cylinder throat correct? This is to prevent gas cutting as it leaves the cylinder as it exits correct?
As best I can measure with my calipers
cylinder throat is 0.359
The forcing cone measures in at .370
muzzle measures .357
The cast lead bullets I bought are supposed to measure in a 0.359, which is under sized as near as I can tell. For my gun I would theoretically need a 0.340 or 0.341. Also even with the 0.359 it may lose a little size due to being loaded into the brass case correct?
Some JHP .357 pass through no problem
some cast coated .357 sized lead are a very light push fit.
For cast lead bullets you want the bullet 0.001 larger than the cylinder throat correct? This is to prevent gas cutting as it leaves the cylinder as it exits correct?
As best I can measure with my calipers
cylinder throat is 0.359
The forcing cone measures in at .370
muzzle measures .357
The cast lead bullets I bought are supposed to measure in a 0.359, which is under sized as near as I can tell. For my gun I would theoretically need a 0.340 or 0.341. Also even with the 0.359 it may lose a little size due to being loaded into the brass case correct?
Some JHP .357 pass through no problem
some cast coated .357 sized lead are a very light push fit.
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