[Unclenick]

A number of the military surplus Mausers I've seen have barrels that were cleaned more often than they were shot, and they can, indeed, have muzzle funneling from cleaning rod rubbing without the throats being shot out. Usually this funneling is biased to one side. You can see it with a flashlight (or even without) The lands just aren't equally tall all around the crown. In a bad case (saw this on a bunch of Columbian m.98's 20 years ago) there may be no rifling at all at the muzzle.

Recrowning with a lathe or with a special crowning tool, like Dave Manson's, is not rocket science. I am astonished you've found nobody to do it or to counterbore to recess the crown. They are common services. You do want to find a gunsmith shop with machine tools, though, and not just a repair bench in the back room, as many gun dealers have. If nothing else, Gander Mountain usually equips its gunsmiths with a lathe. If the fellow they've hired knows his trade, they should be able to do it.

Mr. Guffey has given you good advice on the hand drill and bolt lap for two reasons: One is that rotating a lap in one directions tends to score the surface. It may not matter to function in this case, but it looks poor. You want lapping to be done with a back and forth motion the way engine valves are done. Then you'll get a smooth surface for bluing.

The more important reason, though, is that all the "round head" bolts I've ever held against a radius gauge have turned out to be elliptical in profile. That means, if they aren't fed in on a perfectly straight line with the bore, they will cut the crown at an angle rather than symmetrically. That will never let you reach the barrel's accuracy potential.

If you want a hand lapping method that works, I have one presented in the attached PDF file. It uses a perfectly spherical lap (a ball bearing) and randomizes the pressure angle of the person doing the lapping by rotating the gun barrel repeatedly during the work. You do, however, still need a means of cutting the barrel off square before you start. That's trivial on a lathe because you don't even need to indicate the work to center make a square right angle cut. There are also piloted 90° cutters from Brownells. You can also shorten the barrel with a saw and make the muzzle surface perpendicular to the bore using a file and a square, the way M.L. McPherson is known to do, but this takes skill. You likely won't get it right the first time you try. Once you have the muzzle square and the tools assembled, the process only takes 10 to 15 minutes using graded abrasives.