View Full Version : Crowning muzzle of barrels.

September 2, 1999, 02:34 PM
Got another question...I've heard all kinds of things about crowning. As far as I see it, crowning protects the muzzle, so the "inherent" accuracy of the gun is not last. Lately, i've beeen hearing that crowning the muzzle will sometimes,noticably improve the accuracy of your pistol...Any takers? The pistol i will be considering this for will be a Ruger MKII (5 1/2 bull)...Thanks in advance!

September 2, 1999, 03:07 PM
All I know is that the accuracy will suffer if the crown is not square to the bore.

I've heard that the effects of expanding gases on the heel of the bullet will change depending upon the angle and/or curve of the crown. For ease of manufacture and reliably good results, many target barrels have a compound type of crown--something like 45° just a few thousandths to debur, flat 90° for maybe 1/2 the barrel wall thickness on a counterbore surface, then a 45° or 60° cut to the outer, front-most surface of the barrel crown.

Also heard something about a straight 7° slope from the outer edge of the barrel into the bore, but can't remember anything else.


James K
September 3, 1999, 06:17 PM
Judging by ones I have seen, it would be pretty hard to improve on the accuracy of that Ruger barrel, and a crowning job might hurt, not help. If the major concern is muzzle damage, I suggest just being careful.