Mosin Vertical stringing problem....

Hi All,

I have a Mosin Nagant M38 that was bubba'ed when I bought it (threaded for a .30 M16 style flashider & drilled for a Russian style side scope mt, as well as having a sniper style bent bolt) so it wasn't pristine when I got it. It's been counter bored at some point like most M 38s. The barrel is pretty decent, dark but no pitting. Cleaned it several times with JB bore paste (not too much crap came out, a good thing!) & oiled after with Miltec oil. I have shimmed the barrel under the front band as was suggested by a Russian friend with gasket material and the receiver / action with brass plate. There is no movement whatsoever. The two stock screws for the receiver are very tight & solid, no play in them, so didn't think I needed bedding posts. Also replaced the firing pin spring with a Wolff 30lb. one (old spring was broken). That's what I've done so far.

So the problem I have is that the first two shots are always in the black 10 ring or bulls eye when shooting at 100yd.s when using a bench rest (doesn't matter the ammo), but then as the barrel heats up, the next several shots will continue to climb up after the last (almost like a ladder. Think it's called vertical stringing). This happens with or without the flash hider on and doesn't matter with or without the gasket material (although the stringing isn't as "big or high" with the gasket material in place). It has been suggested to me that I should cut down the barrel just past the counter bore (would be an inch & 1/4) then re-crown it and put the front sight back on. Would anyone have any suggestions to try so to avoid going to this extent?

Thanks for your time.

If you live near Dallas, come by and I'll sell you one of my M44s and forget about it. Maybe the muzzle is climbing out of the vice.??

you may want to slug the barrel and determine the wear.

also, what ammo are you shooting?

If surplus,remember it is .310/.311 diameter and many, many of those barrels are now .315 if not.316 in diameter..not the best for accuracy..

you can cast .314 diam boolits without a custom mold..they don't call it a model 1938 for nothing

No it's .311 (slugged it when I bought it) and it's not an ammo issue. Also not climbing out of the vice. Was suggested on another board to free float the barrel from muzzle to receiver edge (shims only work for the full length barrels so they say) so a business card can pass under the barrel without hanging up, so will try that next.

My barrel slugs at .310

You firing it without the bayonet on? If so, install the bayo and try again. Something to do with barrel tuning.

Etek, The M 38 does not have a bayonet, the M44 does.

Was suggested on another board to "float" the barrel, so you can slide a business card between the lower stock and barrel up to the receiver. They said that shimms under the barrel only help with full length MN rifles, not the carbines. So sanded down the barrel channel in the stock and now can do the business card trick. So off to the range next week to give it a try.

Just an update. Indeed floating the barrel took care of the problem! Very happy with the results!! :cool_smal