View Full Version : recrown rifle barrel
Mongosafari
03-06-2010, 00:29
I got an AR15 upper in trade a few years ago with a little "ding" right on the muzzle crown. I saw this and planned to someday have it recrowned by a gunsmith. Accuracy suffers (I assume) because of the "ding".
Brownells has a hand tool to cut an 11 degree crown in the muzzle. For not too much money.
or
Remove the barrel from the upper and ship it to a gunsmith with a lathe to do the job. I hate having parts laying around for a couple of weeks.
I also have an older Westernfield 22 WMR that would probably benefit from a crown job too with the hand crowning tool.
JimBianchi
03-06-2010, 00:41
I've recrowned a few barrels and when done correctly, it can seriously improve accuracy.
I've seen the tool you mentioned and if I needed one, I'd buy it.
I've used a variety of dremel tools and a low speed drill with lapping compound.
The first one I did took three tries, but after that, I was good to go.
I even did a video on recrowning an airgun barrel a few years ago. It's on Google Video under the search terms I love Airguns. Airgun barrels are much softer steel than firearms so they make it look easy in the video. I took some guff from gunsmiths for my techniques, but I can't argue with success.
I did not do a video on a firearms barrel mostly because at the time I had very accurate rifles that did not need me fooling with them. I wish I still had a pro video camera, I have a second 1022 now that is not nearly as accurate as it should be and the crown looks imperfect.
paddle007
03-06-2010, 07:30
I had an aftermarket 357SIG barrel with a ding. Long range accuracy was not a big concern so I made a simple tool. I brazed a round ball bearing to a steel rod. I tried it be hand but geez it was going to take a long time. Put it in a drill with lapping compound and had it done in ten minutes. May not be uniform enough for some but I can can't visually find a problem with it.
faawrenchbndr
03-06-2010, 07:40
Depending on how large the nick is, you may be able to polish it out.
See the video's available here for an idea
http://www.midwayusa.com/General.mvc/Index/VideoLibrary
Mongosafari
03-06-2010, 08:34
I'm thinking it is just larger than I want to use a brass lap and 600 grit compound to polish out.
Thanks for the responces.
I'll be getting the 11 degree cutter with interchangable brass pilots. I need to measure the 22 WMR to get the right pilot: .213" or .215"
If I need it later add another caliber pilot. Just go slow and a little at a time. I can easily swap out the AR-15 barrel but if I can save two barrels for around a hundred bucks, I'm that far ahead.
Andrewsky
03-06-2010, 13:13
Adco is pretty highly thought-of in the realm of AR-15 barrels.
I have used the Brownells cuters with good results. Make sure you use a good cutting oil with the tools, especially if you use power tools. Also, don't go too fast.
Mongosafari
03-06-2010, 20:08
I have used the Brownells cuters with good results. Make sure you use a good cutting oil with the tools, especially if you use power tools. Also, don't go too fast.
I don't plan on using power tools for the cutting.
Do you also use the brass lap/compound after cutting or just the 11 degree cutter and that's it?
Actually, you'll get better results using a battery powered drill than just doing it by hand. You can't keep the pressure constant through a full circle. But try it, you'll see what I mean. I always cut and then lap. Use a little Clover compound.
Mongosafari
03-07-2010, 08:10
That is what I was curious about. Both (cutting and lapping) need to be done for a complete crown job.
I didn't phrase it correctly; the 11 degree cutter will be by hand and the brass/compound lapping would be using a small electric drill.
Thank you very much for your response.
vBulletin® v3.8.7, Copyright ©2000-2013, vBulletin Solutions, Inc.