My particular "new" 1941 M38 Turk isn't shooting well. Had trouble getting it on paper at 100 yards. Got about a 15" group at 50. I'd already noticed the rifling looked very worn when I got the cosmoline out of it. Got to study it and see whether counterboring might help. Can't hurt. I haven't tried pushing a slug through it yet, but that's next on the agenda. These are good to experiment on. It's not worth rebarreling a $65 rifle, but I might think about doing it just to learn how. But if it's got halfway decent rifling a little way back in the bore, I'll try counterboring. That's easy enough if you've got a friendly neighbor with a drill press, which I do.

Lessee, 5/16" is .3125". Big enough to do a .30 caliber, but not an 8mm. 11/32 is .34375". Probably would work, but might be a bit big. Hmmm, found a drill bit table. There's a size P that's exactly .3230". Might be tough to find. 21/64 is .3281". Now we're talking! Or 8.5mm is .3346". Anybody here counterbored an 8mm? What bit size did you use? I think it's got to be bigger than whatever maximum dimension the worn out bore's gotten to if it's going to clean it up evenly. Looks to me like 21/64" is a good candidate.

Ricochet
Enco will sell you indivdual drill bits of fractional, mumber or letter size for very reasonable prices. Checkout
www.use-enco.com Good Luck Jerry

It might not be worth a new barrel but there are dozens of take-off barrels on the auction sites for almost nothing. I can recall several Turk barrels. Some are close enough to spec that you may even avoid setting back a thread.

Most drills cut a few thousanths oversize unless they are ground perfect which they aren't. You will probably just screw the barrel up terminally with a drill. If you must do this, use a reamer. A HAND reamer and not a chucking reamer. Chucking reamers have a back taper and will only run as straight as the spindle and your setup. They cut just on the end of the flutes.

Exposing my ignorance, but what is it that you are trying to gain by C'bore? You want to float the bullet on the gas going by?????? roger

Thanks for the tips, guys!

Roger, counterboring gives an even, clean end to the rifling. It's basically a deeper crown job. It's an old standard technique used by the arsenals to correct muzzle damage from cleaning rod use.

As for my Turk, it's a moot point. I'm going looking for a Turk (or Swede) takeoff barrel. Counterboring isn't going to help it.

The rifling looked pretty rounded after I'd cleaned the cosmoline out. Took it shooting yesterday and had a real hard time getting any holes on paper at 100 yards. At 50 the best I could do was 15" groups. No key holing, though. Turned out the shiny metal surface was copper-nickel jacket metal fouling. I cleaned out the bore really well with ammonia last night. Came out like dark blue fountain pen ink, darkest I've ever seen. The smooth, shiny metal had been copper-nickel fouling. The clean bore steel is dark and grainy, with sizable chunks of black crud standing up from the surface that survived 30 rounds of firing, lots of patching and brushing. (Probably was surrounded and covered by copper-nickel that the ammonia dissolved away.) The rifling looks like shallow ripples in a sandy beach. I haven't bothered pushing a slug through it, but an inside mic measures .337" across one pair of grooves and .339" across the other at the muzzle. I'm going to need another barrel. I hope it won't be too hard to find, as many of them as have been sporterized. A Swede barrel is said to fit, too. Could be interesting.

Anyway, I'll bet that red splotch on the stock did mean a "training rifle" that was unfit for service. Sure is a pretty one!

And yeah, I know it doesn't make sense to rebarrel a $65 rifle, but I'd like to have the experience. Better to mess with one I don't have a lot invested in, and I can't hurt it, only improve it. The headspace will be a hit or miss proposition as if it ends up excessive I don't have the capability of turning it down on the rear face to thread it in deeper and recut the chamber. I'd be back to looking for another. (Though, come to think of it, a Dremel could be pressed into service as a clumsy substitute for a lathe. For that matter, I could probably strike a deal with the shop teacher at the high school.)