Fixing an off-center crown job???

briang2ad · December 17, 2008, 02:31 PM

Saw a little 22 in a shop. VERY nice shape OTHER than it looks like someone used a high Speed drill bit to fix a crown, and got is a little off-center - more bare metal on one side of the crown than the other. Can this be fixed with a brass lap and hand drill???? Is it hard to do? (Its $75 gun, so I wouldn't want to take it to a smith). Thanks.

Scorch · December 17, 2008, 02:48 PM

If the crown is cut off-center, the only way to fix it is to have someone with a lathe recut the crown (usually this is the best option anyway(. I see a lot of "home-shop" crowning jobs that need to be fixed. Most are from cutting a barrel back, but some are from someone's attempt at accurizing a rifle. I usually buy these rifles, recut the crown, then resell them for more than I pay for them, often the same day.

If the bore is centered in the barrel, anyone can do it on a lathe in just a couple of minutes. If the bore is off-center, or the rifle has an octagon barrel it will be more difficult but not a big deal.

briang2ad · December 17, 2008, 03:29 PM

Thanks. But a recrown here in N VA is $50 +75 rifle = $125 = not.

NAKing · December 17, 2008, 03:45 PM

You might wish to check Brownells.com. They have crowning cutters.

Bill DeShivs · December 17, 2008, 05:53 PM

Some people can do it by hand. Others can't.
Even if the crown looks wrong, the gun may shoot fine.

243rem700 · December 18, 2008, 10:23 PM

If the length of the barrel permits it for legal reasons, couldn't the barrel be cut down and recrowned?

Alleykat · December 20, 2008, 10:59 AM

I guess I was extremely fortunate that a real riflesmith charged me $25 to cut an inch off one of my barrels and recut the crown. (recessed, target crown)

HiBC · December 21, 2008, 02:53 AM

You sure do get to decide how you stack your chips and make your choices.
A piloted crowning tool from Brownells,as I recall,is about $65.With the exception of a person highly skilled at hand work,re-establishing a concentric crown from an eccentric crown cannot readily be done with the ball type lapping tools.A piloted tool that follows the bore is required.
It takes some time to set up a bbl with a 4 jaw and spider,indicating a pin gage in the bore.

Relative to the $85 an hour flat rate you must pay a mechanic,your smith's price is not out of line.

Does your $75 rifle live up to your expectations of a $75 rifle?If it does,perhaps enjoy it as is.If it does not,may I respectfully suggest you paid $75 for what is perhaps a $50 rifle.So really,it is a $50 dollar rifle + $50 for a crown job =a $100 rifle with a nice,fresh crown.Not badThat other $25? Tuition ! I'll bet you check the crown on everything from now on.
You have it,might as well enjoy it.

HiBC · December 21, 2008, 03:04 AM

Thinking about it,if you had about a 3/8 dia round carbide or hi-speed burr that was sharp,you could try putting a chuck or handle on it and twisting it in your hand on the muzzle, (no motor! I mean like in an exzacto saw handle)You can study close and push the chamfer over a little,till it all looks concentric and clean.A little magic marker will help you see the concentric ring as you cut it.I only suggest this because it won't hurt anything to try,given your description of what you have.

Bill DeShivs · December 21, 2008, 03:12 AM

Hacksaw the tip of the barrel off. Use a machinist's square and file the muzzle straight. Then use the ball type crowning tool. Of just chamfer the bore.

Bowhunter · December 21, 2008, 04:11 PM

briang2ad, I have salvaged many a bad crowns with this "fix". If you have a disk sander with a miter gauge (or a friend does) that will "square" up the muzzle and take off as little as possible. Once the muzzle is squared up again, I recrown with a Dremel Tool and ball/bell grindstones by "eye". I have had a lot of experience doing this so can "eyeball" this phase of the recrown. If you are not comfortable enough with this, then set the barrel up on a floor length drill press table and "center" the chuck with the bore center line and use the ball/bell grindstones. This should put you back in the "bacon"!................Dick

December 17, 2008, 02:31 PM	#1
briang2ad Senior Member Join Date: December 19, 2004 Posts: 859	Fixing an off-center crown job??? Saw a little 22 in a shop. VERY nice shape OTHER than it looks like someone used a high Speed drill bit to fix a crown, and got is a little off-center - more bare metal on one side of the crown than the other. Can this be fixed with a brass lap and hand drill???? Is it hard to do? (Its $75 gun, so I wouldn't want to take it to a smith). Thanks.

December 17, 2008, 02:48 PM	#2
Scorch Senior Member Join Date: February 13, 2006 Location: Washington state Posts: 15,249	If the crown is cut off-center, the only way to fix it is to have someone with a lathe recut the crown (usually this is the best option anyway(. I see a lot of "home-shop" crowning jobs that need to be fixed. Most are from cutting a barrel back, but some are from someone's attempt at accurizing a rifle. I usually buy these rifles, recut the crown, then resell them for more than I pay for them, often the same day. If the bore is centered in the barrel, anyone can do it on a lathe in just a couple of minutes. If the bore is off-center, or the rifle has an octagon barrel it will be more difficult but not a big deal. __________________ Never try to educate someone who resists knowledge at all costs. But what do I know? Summit Arms Services

December 17, 2008, 05:53 PM	#5
Bill DeShivs Senior Member Join Date: April 7, 2006 Posts: 11,101	Some people can do it by hand. Others can't. Even if the crown looks wrong, the gun may shoot fine. __________________ Bill DeShivs, Master Cutler www.billdeshivs.com

December 21, 2008, 03:12 AM	#10
Bill DeShivs Senior Member Join Date: April 7, 2006 Posts: 11,101	Hacksaw the tip of the barrel off. Use a machinist's square and file the muzzle straight. Then use the ball type crowning tool. Of just chamfer the bore. __________________ Bill DeShivs, Master Cutler www.billdeshivs.com

December 21, 2008, 04:11 PM	#11
Bowhunter Junior Member Join Date: December 21, 2008 Location: Maine Posts: 12	briang2ad, I have salvaged many a bad crowns with this "fix". If you have a disk sander with a miter gauge (or a friend does) that will "square" up the muzzle and take off as little as possible. Once the muzzle is squared up again, I recrown with a Dremel Tool and ball/bell grindstones by "eye". I have had a lot of experience doing this so can "eyeball" this phase of the recrown. If you are not comfortable enough with this, then set the barrel up on a floor length drill press table and "center" the chuck with the bore center line and use the ball/bell grindstones. This should put you back in the "bacon"!................Dick Last edited by Bowhunter; December 21, 2008 at 06:12 PM.

December 17, 2008, 03:29 PM	#3
briang2ad Senior Member Join Date: December 19, 2004 Posts: 859	Thanks. But a recrown here in N VA is $50 +75 rifle = $125 = not.

December 17, 2008, 03:45 PM	#4
NAKing Senior Member Join Date: August 12, 2008 Posts: 304	You might wish to check Brownells.com. They have crowning cutters.

December 18, 2008, 10:23 PM	#6
243rem700 Member Join Date: October 7, 2008 Posts: 25	If the length of the barrel permits it for legal reasons, couldn't the barrel be cut down and recrowned?

December 20, 2008, 10:59 AM	#7
Alleykat Junior member Join Date: July 26, 2007 Posts: 3,668	I guess I was extremely fortunate that a real riflesmith charged me $25 to cut an inch off one of my barrels and recut the crown. (recessed, target crown)

December 21, 2008, 02:53 AM	#8
HiBC Senior Member Join Date: November 13, 2006 Posts: 8,350	You sure do get to decide how you stack your chips and make your choices. A piloted crowning tool from Brownells,as I recall,is about $65.With the exception of a person highly skilled at hand work,re-establishing a concentric crown from an eccentric crown cannot readily be done with the ball type lapping tools.A piloted tool that follows the bore is required. It takes some time to set up a bbl with a 4 jaw and spider,indicating a pin gage in the bore. Relative to the $85 an hour flat rate you must pay a mechanic,your smith's price is not out of line. Does your $75 rifle live up to your expectations of a $75 rifle?If it does,perhaps enjoy it as is.If it does not,may I respectfully suggest you paid $75 for what is perhaps a $50 rifle.So really,it is a $50 dollar rifle + $50 for a crown job =a $100 rifle with a nice,fresh crown.Not badThat other $25? Tuition ! I'll bet you check the crown on everything from now on. You have it,might as well enjoy it.

December 21, 2008, 03:04 AM	#9
HiBC Senior Member Join Date: November 13, 2006 Posts: 8,350	Thinking about it,if you had about a 3/8 dia round carbide or hi-speed burr that was sharp,you could try putting a chuck or handle on it and twisting it in your hand on the muzzle, (no motor! I mean like in an exzacto saw handle)You can study close and push the chamfer over a little,till it all looks concentric and clean.A little magic marker will help you see the concentric ring as you cut it.I only suggest this because it won't hurt anything to try,given your description of what you have.