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Prc329
11-29-2007, 11:37 AM
O.K., On the guns Randall did for me have a nice, crisp crown that is flat and recessed. Nice and sharp, rifling very clear, etc. The guns shoot very well. The factory gun had an 11 degree target crown.

What is the best to have on a precision rifle? 11 degree recessed crown? I know the recess (am I using the right recess or am I telling everyone to go play outside) is for protection of the crown mainly. Is a flat crown of an 11 degree crown most desired?

rksimple
11-29-2007, 12:09 PM
There was a thread about this over on SH a while back. Under a brake, the protection issue doesn't come into play. I'll look for that thread...

Fjold
11-29-2007, 12:14 PM
I've heard people go on and on about what angle the crown is cut but have never seen a large scale experiment that had any evidence that any angle is better than any other angle.

IMHO as long as the crown is cut even the angle of the cut doesn't matter enough to measure any difference.

Prc329
11-29-2007, 12:31 PM
There was a thread about this over on SH a while back. Under a brake, the protection issue doesn't come into play. I'll look for that thread...

For my rifle it would. I will be running an FTE brake so I can easily remove my brake for cleaning. I'd hate to screw up my crown while the brake is off.

sloguy
11-29-2007, 1:05 PM
For my rifle it would. I will be running an FTE brake so I can easily remove my brake for cleaning. I'd hate to screw up my crown while the brake is off.

to damage it youd have to bang it on somthing pretty hard. its naturally slightly recessed anyway. what are you planning to do while cleaning thats so violent? drop it barrel pointed at the ground?

when i crowned one of my 22 rifles, from the factory crown to my 11 deg crown i cut my groups in half. when cleaning it ive purposely tried to damage the crown with my aluminum rods( why not, i can just recrown it since i have the tools). havent seen any loss of accuracy.

Prc329
11-29-2007, 1:09 PM
I can be a little clumsy :D

rksimple
11-29-2007, 1:17 PM
I can be a little clumsy :D

I wouldn't worry too much about damaging it while the brake is off for cleaning. Just be careful! I'd worry much more about dinging it on something during a match or while hunting.

rksimple
11-29-2007, 1:22 PM
Here's (http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Board=17&Number=347392&Searchpage=4&Main=32023&Words=crown&topic=0&Search=true#Post347392) that thread on SH. Doesn't seem like it matters what type for accuracy, just that recessed is more protected.

Prc329
11-29-2007, 1:31 PM
Thanks for the link.

ar15barrels
11-29-2007, 1:33 PM
The 11 degree crown comes from the benchrest crowd.
Someone once figured out that it was the best angle to use with a specific boattail bullet so that the gasses escaped around the base of the bullet with the absolutely least disruption to the bullet.

Keep in mind that this only applies to un-braked barrels.
When you put a muzzle brake or anything else that traps gas, it won't matter anymore as there's already something else to make gas turbulence.

The most important thing is that the crown is perfectly perpendicular to the bore.