Thread: Resurgence of interest in the old "Three Oh"?

if you think about it,a two groove barrel,is something like 80?% at .303 of an inch sized hole...so a .308 sized projectile gets 5 thou grip over 80% of its surface....

Originally Posted by Micky Duck

if you think about it,a two groove barrel,is something like 80?% at .303 of an inch sized hole...so a .308 sized projectile gets 5 thou grip over 80% of its surface....

Greetings Micky and Scout,
That was my thinking. Some data for the two groove barrels that I found gave the bore at .304" and the groove from .316" to .318". The dimensions were developed to suit the Mk VII projectile and gave decent accuracy and long barrel life. Tests with the 175 grain Hornady round nose often give two shots touching at 60 metres but different lots of projectiles can give quite different points of impact. Current production has a blunter shape.
Regards Grandpamac.