off-center muzzle crown?

kalibos · #1 05-14-10, 20:41

if the muzzle crown is cut slightly off-center, will it affect the accuracy?
i just noticed while cleaning one of my rifles that the crown is not cut centered to the bore.

JSantoro · #2 05-14-10, 23:16

Do you mean that the crown itself is uneven? If so, yes, it can.

Or, do you mean that, when observed from the muzzle end, that the bore is not dead-centered within the material of the barrel? If this is so, the answer is still yes, but for different reasons than a jacked-up crown, and in ways that are predictable. It's not a show-stopper.

Fireglock · #3 05-15-10, 00:07

This link is from the ADCO website, it might give you some further insight.

http://www.ar15.com/forums/topic.htm...f=130&t=158403

kalibos · #4 05-15-10, 05:46

i mean when i look at the muzzle, the crown is not cut centered to the bore and not even around the hole

rat31465 · #5 05-15-10, 09:58

Can you post a pic? A bad crown can have a detrimental effect on your accuracy. Afterall, the crown is the last point the bullet touches as it exits the barrel.

Robb Jensen · #6 05-15-10, 10:12

A bad crown or a non-concentric to the bore threading can cause accuracy problems.

kalibos · #7 05-15-10, 16:16

does anyone sell a tool so that i can recrown it myself? i hate having other people do things for me that i can do myself.

Iraq Ninja · #8 05-15-10, 16:33

Never done one, but here is a video from Midway:

http://www.youtube.com/watch?v=b43odFm0mrI

Just remember that these tools are made for gunsmiths, or people with the skills and talent.

kalibos · #9 05-15-10, 17:14

i find that if i do things myself that they usually turn out better than when i send them out to be done since it is mine and i'm a bit OCD about my things

Quote:

Originally Posted by Iraq Ninja

Never done one, but here is a video from Midway:

http://www.youtube.com/watch?v=b43odFm0mrI

Just remember that these tools are made for gunsmiths, or people with the skills and talent.

bkb0000 · #10 05-15-10, 17:58

i'm a part-time gunsmith, and I dont do thread/crown. it's the only thing i dont/wont do. the tools and tooling required for an even adequate job are deep into the thousands, including a quality lathe and specific tooling. i highly, highly recommend getting any muzzle work done with a highly regarded smith known for doing good muzzle work.

kalibos · #11 05-15-10, 21:16

i wish i could post a pic of it, my cell phone camera is all i have right now and it can't focus that close up.

it may be nothing to worry about, i've shot it several times and it doesn't seem to be affecting it but i have only shot it out to 50yds.

the tool that is used in the video above doesn't seem to terribly hard to use... it probably isn't the best method but i assume that it is what most gunsmiths would use to do a re-crown?

kalibos · #12 05-15-10, 21:21

then again, how often would i use that tool if i bought it?
probably WOULD be a better idea to just send it to ADCO or somewhere

Stephen_H · #13 05-15-10, 21:29

I'll ask the obvious question here; how does it shoot?

Stephen

bkb0000 · #14 05-15-10, 21:29

if your bore isn't perfectly concentric to the barrel OD, then a hand ream would pretty much be the only option, assuming you couldn't or wouldn't turn the whole barrel down to true it up. i'd be concerned about damaging the rifling at the muzzle with a hand reamer, i'd also question just how concentric you can get.

i'm pretty sure just about every asshat turns their barrels these days, however- out-of-center bores seem to be pretty rare. this in mind, a lathe job at ADCO is going to give a WAY better crown than anything you can do with a hand reamer. and if they fuck it up, you get a new barrel. if you fuck it up, you get to BUY a new barrel.

Fireglock · #15 05-15-10, 21:32

Quote:

Originally Posted by kalibos

the tool that is used in the video above doesn't seem to terribly hard to use... it probably isn't the best method but i assume that it is what most gunsmiths would use to do a re-crown?

I personally would take a dim view of a "professional" using the lands of my barrel to cut the crown on one of my barrels. The demonstrated method looks to me like a poor man's method.

kalibos · #16 05-15-10, 23:31

i was thinking aboput adding a suppressor down the road so i guess it wouldn't be a bad idea to just go ahead and get the threads re-cut concentric to the bore and recrowned at the same time

Spooky130 · #17 05-16-10, 09:03

If you plan to hang a suppressor off that barrel I would quit now and get a new barrel from a reputable source. No sense in blowing out the side of your can and that $200 tax stamp.

Spooky

boltcatch · #18 05-16-10, 21:25

Are you sure it isn't just a crown that looks off center due to the excess chrome lining coming out the front?

I've seen both - off center crowns, and those that at first glance looked off-center.

kalibos · #19 05-16-10, 22:47

the barrel is from a reputable source, the bore doesn't look off-center just the crown.
just thought it would be a good idea to get it rethreaded just to be sure while it was getting recrowned...something i was going to do anyway before adding a suppressor

Quote:

Originally Posted by Spooky130

If you plan to hang a suppressor off that barrel I would quit now and get a new barrel from a reputable source. No sense in blowing out the side of your can and that $200 tax stamp.

Spooky

it's definitely not the chrome lining, i'll try and get a decent camera so that i can get some pics up of the crown

Quote:

Originally Posted by boltcatch

Are you sure it isn't just a crown that looks off center due to the excess chrome lining coming out the front?

I've seen both - off center crowns, and those that at first glance looked off-center.