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Ghost101
11-13-2012, 08:09 AM
First off, I'm not an expert on doing any of these things that I'm about to try. I'm getting a lot of leading from my S&W .500. Using a Lee 440gr. GC, water dropped boolit.
I have slugged my barrel at, .500, .501, .5001. My cylinder measures out to .499.
I was going to hand lap my bore with LBT lapping compound, until I slugged my bore an it wouldn't pass thru the cylinder.
Question being, how much larger do I want the chambers to be over the bore ?
I plan on doing this per LBT's instructions with his kit. But no mention of how much bigger I need to go.
At some point I want to order more molds for this gun besides the Lee. And sure don't want to order dies of the wrong size for my Star.
Thank You

GBertolet
11-13-2012, 09:00 AM
Idealy, about two thousandths over bore size.

Ghost101
11-13-2012, 05:41 PM
Thank you GBertolet for the info. Veral at LBT can be hard to reach by phone. A little scared about
messing with the cylinder, but will go slow. thanks again.

leftiye
11-20-2012, 06:15 AM
Barrel bore is one thing, and lapping that is your decision. Chamber mouths should be made (if not done so during manufacturing) .001" (or .002") over GROOVE diameter. There is much info (many threads) here about opening up chamber mouths.