3-4 MOA par for the course on 91/30?

[lowflier]

I got my 91/30 back to the range and ran a few groups of 5 shots, with a 5 minute break in-between (waiting for the firing line to "go safe"). Like last week, I seemed to have one high flyer in each group of 5; it's possible that the barrel is changing as it warm (or I just lose concentration 20% of the time ): (2nd image below).

Average vertical group size was 6 MoA. Average horizontal group size was 4.1 MoA. (vertical spread was 50% bigger than horizontal). Good news is, 6 MoA is within the black bullseye on standard targets. Bad news is, I was shooting from a bench

For reference, I then shot a M1917 (attached). Average vertical group size was 2.8 MoA; average horizontal was 3.5 MoA (vertical was a tad tighter than horizontal, but basically even). I think the m1917 benefited a bit with the peep sights and better trigger, probably about 25% reduction in group size. But 91/30 vertical grouping was 50% bigger than the M1917.

Can anybody recommend a torque value for the action/tang screws? I think I have mine at 18 in-lbs each.

[Edit: I see another thread showing three groups of 5 shots; they appear to average 3.4 MoA vertical group, and 4.6 horizontal. ]

[Junk Yard Dog]

I tighten them firm by hand, never checked the torque, the US M1917 was designed as a precision marksman's tool, the 91/30 as a basic infantry rifle used by an army that did not put great emphasis on individual marksmanship. The Russians went for massive numbers, while the British ( who designed the US M1917) and the US army went for smaller numbers and higher skill level with the rifle. The stringing sounds fairly typical of a basic Soviet 91/30 as it warms up. The Finn M39 will give the M1917 a run for it's money, but the Soviet Mosins rarely will, and then only by chance.

[lowflier]

What causes the muzzle rise with a hot barrel? I see a few things people are doing for general accuracy:
- shim the action, using 5 to 20 thou brass shims
- tighten the action screws to 30-40 inch lbs
- float the barrel a bit (permanent change)
- bed the barrel under the forearm band with oiled felt, cork; or even bed the whole barrel length

It seems like if the hot barrel is bending upwards, then either the first or third might help. I have good accuracy between two shots with the barrel cold, or two with hot barrel, so I think the crown is good and the action is tight enough.

[desdem12]

You can float the barrel maybe by shimming the action and that would not be a permanent change. That is what the finns do. Also you may try without the handguard. I would just take a week camping (at the range) with all the stuff and try each little thing and see which one works best.

[polymerase2]

I find with my aging eyes that aperture rear sights are more accurate. I may not be able to focus on them, but I get a consistent fuzzy ring to center the front post. The Enfield, Garand and the target .22's are nice. I'm watching for a 1903A3 someday.

[lowflier]

I agree: I need readers, and I see double-images of the rear sight. The two overlapping circles I see from a peep sight or ghost ring works better than double-image rear open sights. That said, I prefer the cheek-weld I get on the 91/30 over the M1 or M1917!

[Warf51]

It's not always the fault of the rifle, sometimes it's the ammo, Mosins are notoriously picky about ammo, swap to another country's cartridge, or another lot and POI can change. Also keep in mind that many of us are older now, and can't see for shit anymore.

Boy that is the truth! Yes,,,,3 or 4 is perfectly OK with an Iron sighted rifle at 100. Matter fact,,it is good!