Skip to main content
Help Center Community Shop

bullet vs bore diameter

MVP
I have heard about Ruger Mini 30 being hammer forged with their .308 rifle barrel mandrels and how it is one of the causes for there to be a lacking in accuracy because of the 311 diameter of the 762x39 bullet.
Forcing a .311 bullet down a .308 bore.
What got me thinking about this is
I measued the bore on an old 9.3x72 rifle and it is measuring .358 and available bullet diameter is .366
This doesn't seem right to me.
What am I missing, will there be excessive pressure or is it going to be ok to handload the .366 bullet and fire it down a .358 bore?
0

Comments

4 comments

Date Votes
  • 788-308
    "Groove Diameter"

    Bore is the small dimension of a barrel, while groove is the large.
    0
  • MVP
    quote:Originally posted by 788-308
    "Groove Diameter"

    Bore is the small dimension of a barrel, while groove is the large.


    Thanks for the correction[:)]

    My groove diameter is .358.
    0
  • Rocklobster
    BTW, the first run of Mini 30's were the only ones with the .308 bore. Multiple reports of pressure problems caused Ruger to change to the correct bore size on subsequent runs, and they replaced barrels on any rifles with the wrong bore for free.
    0
  • 788-308
    You do have a bore dia. of .358", groove would be .366" +/-. [:I]Have you slugged the bore of the rifle?
    0

Please sign in to leave a comment.

Recent Activity