shot out rusted out mosin??

[RyanJames170]

I have a old 1923 mosin that i would like to see shoot cast at some point, currently its being fed a diet of various jacketed bullets.
the bore on it measures .318 in the groves and .305 on the lands, it can shoot .308 diamater bullets with some degree of accuracy approximately 2-4" at 50 yards and with .311 russian bullets it will tighten that up to 2" and 4" at 100 yards,

the barrel was rusted pretty bad when i got it and is pitted pretty bad due to probably corrosive ammo and being in a house fire. the rifle did not get hot at all but did get a little wet and rusted in the fire.

now this rifle can chamber a unisized NOE .316 mold that measures in at .318 unisized. but i can tell the case is touching the throat in the neck aria.

if i wanted to try shooting cast out of this thing how could i go about opening up the neck? and would this bother my accuracy with jacketed bullets?
also what would i wanted to do for a bullet size, lube and preparation to get this thing to shoot cast?

[Larry Gibson]

I've helped get a couple similar MNs shooting reasonably well with cast bullets. Might do a chamber cast as many MN chamber necks simply taper from chamber into the throat with little or no chamber mouth step. Trimming the cases to a shorter OAL can allow the .318 bullets to chamber in Norma cases. Some other cases have thicker necks and neck turning is the option there. A custom reamer to ream the chamber neck would probably be cost prohibitive.

I also found a Lyman 323470 (160 gr 8mm bullets. Sized and GC'd at .325 then run through a .318 sizer makes and excellent bullet for such. However, your NOE 316299s at .318 "as cast" should work quite well.

[Outpost75]

A .345" chucking creamer from McMaster-Carr is $28 and will open the neck to accept larger bullets, using a simple bushing made from a cartridge case with neck cut off to align the reamer shank in the chamber body.

[GregLaROCHE]

Depending on how the bore looks after firing the jacketed bullets, you may want to investigate fire lapping. I’m sure there are posts about it if you use the search box. Also it’s always a good idea to slug the bore to know for sure what the diameter really is.

[RyanJames170]

After firing a good number of Russian steel jacketed bullets that have a heavy skirt the bore is starting to get closer to bare metal inside all but it still dark looking with tons of pitting.

I did actually slug it lastnight and with its size I ended up deciding cast might not be out of the question, as I was under the impression it was a bit bigger in size.

Would a GC .318 bullet have a chance in hell of working or would I be better off with something at .319?

[.455 Webley]

How are you determining that the case is touching the throat as you say? It's possible that seating slightly deeper may help your issue. What is the inside diameter of a fired case mouth? That figure subtracting a couple thousands of an inch for the case to release the bullet should give you the biggest diameter you can chamber. If you want your as cast .318 to get a little bigger you can try a few dirty tricks. I have read that an aggressive lean on a lubrasizer handle can bump up a bullet. This is with a correctly sized die and good fitting nose punch. You can beagle the mold and then size down to where you want to be. Or you can powder coat and size to where you want to be , or perhaps the PC would get you just that 1 of 1.5 thou that you are looking for.

If you are not set up to PC I can do them for you. I am just up the road from you.

[GregLaROCHE]

You don’t say what size you found it was after slugging it. That’s what will determine what size boolits will probably work best in it.

[starnbar]

I have worked on some old mil rifles and you might be surprised at the accuracy after a little work on them. Hey it is a crap shoot unless you go with a new barrel and even then it might not be much better than what you can get by yourself

[RyanJames170]

I slugged the bore lastnight at .318/.3175 in the groves one grove is a little bigger then the other, the lands are .305 and .303 one being bigger then the other. The slug I drove threw it was about .50” long and stated out over .355” with a nice taper at the nose to start it. My cousin made them with 9x18 casings.. oddly enough they work good for making slugs.

The case neck showed small amounts of whitnessing from touching, and I used the proper NOE neck expander for the .318 bullet.

[Larry Gibson]

After firing a good number of Russian steel jacketed bullets that have a heavy skirt the bore is starting to get closer to bare metal inside all but it still dark looking with tons of pitting.

I did actually slug it lastnight and with its size I ended up deciding cast might not be out of the question, as I was under the impression it was a bit bigger in size.

Would a GC .318 bullet have a chance in hell of working or would I be better off with something at .319?

A .318 cast bullet should work fairly well. The T53 (Chicom M44) I brought home from the late SE Asian war games has a real sewer pipe barrel. With the 3 rounds of ammo still in it when I picked it up it wouldn't hold a C-Ration cast lid at 50 paces with the one bullet hitting was wobbling bad. When I got home Norma ammo with .308 bullets was hopeless. I wore out numerous bore brushes and used up a lot of older milsurp bore solvent and Hoppe's scrubbing the bore. In '68 I tried some .312 jacketed over H4895 and they held about 8-10" +/- at 100 yards. The T53 was basically just a wall hanger. Some years later i was helping a guy load for an odd ball 8mm drilling cartridge that needed.318 bullets. I got a .318 H&I die and already had some 323470s GC'd, sized and lubed at .325. I removed the "I" rod from the "H" die and used it as a push through in the 450 lubrasizer. The 323470s sized down perfectly. They shot extremely well also.

As an after thought I dug out the one box of 7.62x45R Norma cases I had used with the T53 and those .318 sized 323470s were a slip fit in the fire formed necks. I had already shortened a Redding 284 Win bushing die for use with different bushings to NS cases for my other MNs as The FL dies would size the necks for use with .308 bullets. Appropriate NSing gives almost forever case life, especially with cast bullet loads and using the Lee .308W collet die with a washer over the case will size the necks appropriately also. Thus with the necks sized to give .002 - .003 tension on the bullets a Lee Universal Expander was used to flair the case mouths slightly. If i recall correctly I loaded them over 12 gr of Unique and found they were pleasantly accurate at 50 yards. I used an NECCO firelap kit and fire lapped the bore. Since then I've gotten a group buy Lee 6 cavity C314-291 that drops the bullets at .317 - .318. I just GC and lube them in the .318 H&I. Loaded over 30 gr 4895 with a dacron filler they shoot right around 3 - 4 moa at 100 yards which puts the old T53 "back in service" shooting as good, if not better than, other MNs with much better bores shooting milsurp ammo.

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