Mosin shim update......

[snayperskaya]

I shot my 91/30 on Saturday and whilst the trigger was very satisfactorily the accuracy wasn't so on getting it home it was promptly stripped.After a bit of measuring and checking and then checking again I thought "what would a conscript from the Urals do?" and promptly knocked up a set of shims from an old tobacco tin and fashioned some suitable strips from an old canvas pouch and set to work.I worked out the entire length of the barrel was held tightly by the forend of the stock and the upper handguard so with some sandpaper wrapped around a suitably sized socket I sanded the channel in the stock until I got to the point where once the barrelled action was back in the stock I could freely slide a sheet of paper,placed between the stock and the barrel,along the entire length of the barrel.
Once I was happy I placed the strip of lightly oiled canvas around the barrel at the point of the front retaining band and reassembled everything, being careful to just snug the action screws not overtighten them.The other thing that was apparent was the fact that with the rear sight set on "1" at 100m it shoots approx 10-12" high so I have cut the hollow plastic tube of some cotton buds into suitable lengths, each one progressively 0.5mm longer, and will experiment with them when I next go to the range to test it.I have fitted a 2mm longer one over the original front sight post, it is a nice snug fit, and once it was given a lick with a black Sharpie pen you can't tell the difference between it and an original post and the sight picture is perfect.

So following on from that this morning I've used the same process on my M44 carbine which has taken a bit more work as the stock was fouling the barrel and action everywhere but after some sanding and shimming the barrel was fully floating a treat and after wrapping the barrel with the canvas I can slide a tube of paper between the front of the forend and the upper handguard freely down as far as the canvas so I know the muzzle end is not clamped tight anymore.
Once I get them to the range again I'll be able to see how much improvement I've made so it should be interesting.I have researched this before I started and the mods I've done are Russian and Finnish mods that are well documented so hopefully.......

Here's a pic of the version 1.0 shims I knocked up from the 'baccy tin, not "laser cut" but hey-ho



Cotton bud stick front sight post, 2mm longer than the original

[Demonic69]

Nice work, when you shooting them next? We're you tempted to see if free-floating the barrels was better before the canvas?

[snayperskaya]

Cheers, I'll hopefully get to the range next weekend.I did think about trying the barrels free-floating but the canvas wrap around the barrel at the the front retaining band was the technique used on Mosin sniper rifles by the Russians, and I believe the Finns, so this is what I've attempted to replicate as it apparently dampens the whip of the barrel without clamping it tightly.

[Rearlugs]

I think the front barrel wrap is actually intended just to stop the top handguard moving and thus altering the POI.

[Mezzer]

My goodness, that front sight housing looks as rough as a mustelid's a*se (with apologies to Badger)

Mezzer

[snayperskaya]

My goodness, that front sight housing looks as rough as a mustelid's a*se (with apologies to Badger)

Mezzer

The old girls seen some action in her 76 years and isn't pretty, by comparison the unissued M44 looks as though it came out of the factory recently!


Regarding the barrel wrap this is from a Mosin forum and seems about right....


If you measure the barrel on a 91/30 you will see that from the receiver to the tip it is give or take 28 inches long depending on whether or not the crown has been re-cut during refurb. The wrapping is centered on the front barrel band spring which is about 7 inches back from the crown. If you divide the barrel length into four equal segments you get each segment measuring 7 inches. Extending the felt wrapping 5~7cm also covers the area of five equal divisions of the barrel length or 5.6 inches. So effectively speaking the felt is dampening the fourth and fifth harmonics of the barrel's vibrations. Those harmonics are dissonant harmonics. A fourth harmonic is the sound you hear when you lean on the horn of your car and the fifth harmonic are those power chords you hear in loud rock and roll music. The third and sixth harmonics are sweet tones.