Do they make a tool to Re-crown the Barrel?

Yes Brownell's carries several crowning tools, the cheapest hand tool being $150 bucks.
http://www.brownells.com/.aspx/pid=18282/Product/BRASS-ONE-CALIBER-SET

For a one-time job on a mil-sup rifle?

Go to any hardware store and buy a large round-head brass screw, and a tin of 240 grit lapping compound.

Chuck the screw in an electric drill, apply the lap to the muzzle and screw head, and gofer it.

Keep the drill moving in oval circles and the round-head brass screw will lap a perfect crown.

With that said, many Mosens have pretty serious muzzle wear from 90 years of steel cleaning rods. But that wear is inside the muzzle, and re-crowning will not help anything at all.

The answer then is to counter bore the muzzle about 1" deep with a drill slightly larger then the bore.

The drill will leave a perfect crown inside, just not outside on the end of the muzzle.
For best results, I get someone with a lathe to do it.

rc

So long as done correctly, it is easy to crown a muzzle.

(Would add to video below, that when filing to help insure one is staying square to muzzle. File until file marks show across surface of muzzle, then switch and file 90 degrees to original filing until cross hatch pattern is removed, repeat 90 degree process until satisfied.

Video from Midway: http://www.youtube.com/watch?v=OorpZlG28fI

http://www.google.com/#pq=do+not+ta...w.,cf.osb&fp=935a0bef009a2890&biw=720&bih=349

The original re-crowning tool for Mosin rifles that Russians supplied to their armourers looks just like the tool sold from Brownells - brass pilot, angled reamer and a T handle. And this tool is used only for field repair - never for factory refurbishing. They did not supply "barrel crowning files" for sure. One just can't get a flat surface with a file, let alone for it to be perpendicular to the bore. You simply can't.

Boris

What you mean is "YOU" cannot get a flat surface with a file. 99.999% of people have no idea when it comes to filing correctly, it can approach an art.

I wrote this up years ago for American Longrifles:

http://www.americanlongrifles.com/Workshop_Fitting_Breechplug.htm

http://www.americanlongrifles.com/WorkShop_frame.htm

I'd still contend the problem, if there is one, is far more likely to be cleaning rod wear down inside the muzzle then a bad crown.

rc

Yes, hang fire - I can't do it. But can you guarantee me to cut a muzzle crown, that is perfectly flat and perpendicular to the bore line with just a file? Without even knowing where exactly is that bore line? Hint - machinist's square will give you a false reading in this case. Furthermore - it is not precise enough. You are describing a muzzleloader breech plug fitting and recommend it for barrel crowning - this is not correct sir.

Rc, very good question - is the owner 100% sure, that his rifle needs a re-crowning done?

Boris

rcmodel said:

I'd still contend the problem, if there is one, is far more likely to be cleaning rod wear down inside the muzzle then a bad crown.

rc

Click to expand...

I agree...

DM

Re Mizar:

Yes that article was for fitting a breech plug. But I use the same exact procedure for filing a muzzle square prior to crowning, tapered barrel or straight.

An aside, but IIRC, some of the most accurate barrels produced by Harry Pope and his contemporaries had no crown at all for the muzzle, but were as flat and square as they could make them.