New 629-6 Muzzle crown concern

Hi,

I just bought a new Smith 629-6 and noticed the muzzle crown has a slight machine tool mark on it and looks a bit rough.

Should I be concerned with this affecting accuracy?:confused:
 

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The nick at the end of the barrel doesn't mean a thing . I would, however hone that junction between end and bore , that's the important area !
 
Where?

Hi,

I am not exactly sure which area you mean.... :confused: Is there any way you could indicate the area? Also I am not even sure how this can be done. :confused:

Does the barrel need to be removed?:eek:

My lat S&W 44 was a 29-2 in blue so imperfections were not as noticeable...
 
That muzzle area does look kind of raggedy.
But that little nick isn't on the muzzle.
If you have to ask how........
Why are you asking us if it affects accuracy?
Your gun will tell you better than we can.
 
Find a roundhead brass screw or carriage bolt with a head larger than the bore diameter.

Chuck it in a drill and coat it with a fine grinding compound or a good metal polish and with the barrel in a vise, use it to square up the end of the rifling until it's the same all around the circumference.

It should only take a few minutes
 
None of my drills run straight enough to do that.
They're ok for drilling holes and such, but not for machining.
What brand of drill will?
 
All he is saying is that you don't need a metal lathe to perform this operation and any 3/8" electric drill will suffice. Frankly, all this muzzle crown concern is way overblown for your average handgun. That little flaw is meaningless unless you are paying an absurd amount of money on your firearm.
 
This is a new S&W?
Send your picture to them and see if they will fix it. That gun looks like it has been kicked around for years!
 
None of my drills run straight enough to do that.
They're ok for drilling holes and such, but not for machining.
What brand of drill will?

It doesn't have to be perfectly straight to be effective.

All you're really doing is removing the burrs and imperfections by removing a few thousandths at a time.

The round head is self centering.

You can buy a hand tool to do the same thing, but the drill is faster and cheaper and gives the same end result
 
How is Smith & Wesson's service on new weapons that are returned for service?

I was thinking of returning it but I am afraid that I might get it back in worse shape...

Do they ever just give you a different weapon? :confused:

Thanks
 
They will replace guns that can't be repaired.

You "problem" is a 10 minute fix with hand tools.
It's more cosmetic than a real problem.
 
RE: Will S&W replace my gun

The muzzle crown is not the only issue....
The trigger has a negative sear engagement and is subject to push... a safety issue.:eek:

I was thinking of having a gunsmith here deal with the trigger.... honing the muzzle is not something I had considered. Maybe it's better to send it to S&W... Not sure what to do.:confused:
 
The trigger issue is much more worrisome than that little nick on the nuzzle.

I say send it back and let Smith & Wesson repair both issues.
 
I've always checked crowns after machining by running in a Q-tip and then pulling it out. If there is a burr it will pull off cotton from the Q-tip.
 
Not me

I wouldn't go near the muzzle crown with any hand held cutting tool or hone. I would think gunsmith time or send it back to factory or lathe time and I'm not past tinkering with or adding aftermarket parts but the muzzle crown has to be about 100%,,, the one exception might be a cutter or stone that had a guide rod that fit into the muzzle bore tightly to keep it exactly square with the bore
bb
 
I wouldn't go near the muzzle crown with any hand held cutting tool or hone. I would think gunsmith time or send it back to factory or lathe time and I'm not past tinkering with or adding aftermarket parts but the muzzle crown has to be about 100%,,, the one exception might be a cutter or stone that had a guide rod that fit into the muzzle bore tightly to keep it exactly square with the bore
bb

Too many think a muzzle crown has to be "perfect" to get good accuracy when reality is it's nowhere near as critical as some would have you believe:

https://thefiringline.com/forums/archive/index.php?t-517374.html

JimPage
February 23, 2013, 10:13 PM
A friend of mine crowned his barrel with a marble epoxied to a bit shank. Then he put emery cloth on the marble and chucked in a hand drill. He gets exceptional accuracy for the gun... I can't recommend that procedure as it is so unusual. But it's hard to argue with success. Of course, he only did it to the one gun.

Step by step instructions:
http://www272.pair.com/stevewag/muzzle/mz.html

I've done several with just the bolt and metal polish instead of grinding an entire new crown.

The OP's gun would only take a few minutes to polish out the imperfections.
 
Buzzard Bait,

I have a lathe, but I still use the ball lapping method. I came up with it probably the same way others have; when I was younger and short of cash, but shooting what little money I had up in matches, where I wanted a rifle that grouped as well as I could get it to. Since I have a lathe these days, I usually cut the muzzle square on it and do and outside chamfer on it, then go to the ball lap. When I was young and poor and didn't have a lathe, I scraped together money for one of the 90° cutters that Brownells sells and used that.

The reason I like the ball lap is that a sphere is self-centering over a square hole, and as long as the muzzle starts square, that center will be the bore axis. I've also cut crowns on the lathe, of course, but a right angle cut is the only one that doesn't require centering. So I can to that square cut on the 3-jaw chuck and it's good enough for the outside chamfer. To cut a crown, though, I have to center the bore in the 4-jaw chuck, and by the time I've swapped the chucks, turned a brass mandrel that kisses the rifling to get a smooth concentric surface to make indicating the center easy, and then actually adjusted to the chuck true, the ball lapping is done and is geometrically perfect. The result is also cleaner looking as it produces no tool marks.

I prefer the ball to the round head screws, because the latter usually are not actually round but elliptical in profile, so they don't truly self-center and depend on the fellow operating the tool to randomize the angle to a true average. Also, I don't like using something that only turns in one direction. That does produce scratchy looking tool marks from the removed metal balling up and scratching itself, where the back-and-forth motion I described for lapping doesn't make any. It's the reason engine valves are ground that way.

I've seen photos of M.L. McPherson cutting off and crowning his barrels at the range to tune them. Hacksaw, square and some files to get the end squared up. Glass marble rolled under his palm for a lap to cut the edge recess. Same self-centering principle.
 
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