blackpowder ruger #1 breech plug

[lazylabs]

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Did you cut the inside of the case head to uniform it or did you just cut the end of the plug to match as close as you can to factory shape?

 

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Most of my cases use a 209 primer and do not require very close headspacing.
The H&R is the only rifle that requires a LRM primer and those cases need to be machined on the ID to ensure about 0.002 clearance.

Everyone has their own thoughts on headspace. I prefer a 209, but most use a standard case.

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