Flash hole diameter

justin amateur

Sergeant
Full Member
Minuteman
Apr 21, 2012
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I've recently taken up reloading 223, as it's an inexpensive cartridge
with a large assortment of bullet weights and styles.
Read everything I can find, ask questions of more experienced shooters,
and one question seems to have very few answers:

Is there an optimum diameter for flash hole size?
Is there any data available on how hole diameter is determined?

Found a pdf of a Masters Thesis on line, 200 plus pages of information.
Interesting conclusion regarding 223 and 308 flash holes.

Link to download pdf of research document
 
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