From my collection of WW2 sniper rifles the Mosin PU is one of my favorites.
Tip#1
On many occasions I have noticed the shots gradually begin to rise as the firearm warms up.
To counter this from happening remove the upper hand guard and lay a strip of heavy duty tin foil along the top of the barrel. Place it shiny side down then reinstall the upper hand guard.
This will reflect heat downwards, keep your upper from discoloration and possibly cracking.
Now your shots will hold a much tighter group. This is due to preventing heat rise that escapes the top of the rifle barrel. I believe the top of the barrel contracts slightly, bending it like a "U". Reflecting heat back down seems to slow this contraction.
I tried this tin foil below the barrel with absolutely no change in performance. The only benefit is your stock is protected from heat.
I imagine someone using these PU's didn't fire 20 rounds consecutively so maybe it wasn't an issue back then.
Tip#2
Teflon tape around the barrel, applied directly under the front barrel band. Add about 0.040"(1mm) in the diameter, test fitting required to get a snug fit.
Tip#3
When the bolt is closed and ready to fire. Lift the bolt handle up a C-hair so it doesn't bounce on the reciever when firing. Try this dry firing and you will typically feel much less vibrations immediately after the trigger is pulled.
Tip#4
Remove the cleaning rod they don't fit snugly and can bounce a bit.
These simple tips apply to most bolt rifles. Keep in mind they are all just observations and numerous tests to reduse harmonic frequencies in the barrel. I'm not an engineer or firearm professional.
Tip#1
On many occasions I have noticed the shots gradually begin to rise as the firearm warms up.
To counter this from happening remove the upper hand guard and lay a strip of heavy duty tin foil along the top of the barrel. Place it shiny side down then reinstall the upper hand guard.
This will reflect heat downwards, keep your upper from discoloration and possibly cracking.
Now your shots will hold a much tighter group. This is due to preventing heat rise that escapes the top of the rifle barrel. I believe the top of the barrel contracts slightly, bending it like a "U". Reflecting heat back down seems to slow this contraction.
I tried this tin foil below the barrel with absolutely no change in performance. The only benefit is your stock is protected from heat.
I imagine someone using these PU's didn't fire 20 rounds consecutively so maybe it wasn't an issue back then.
Tip#2
Teflon tape around the barrel, applied directly under the front barrel band. Add about 0.040"(1mm) in the diameter, test fitting required to get a snug fit.
Tip#3
When the bolt is closed and ready to fire. Lift the bolt handle up a C-hair so it doesn't bounce on the reciever when firing. Try this dry firing and you will typically feel much less vibrations immediately after the trigger is pulled.
Tip#4
Remove the cleaning rod they don't fit snugly and can bounce a bit.
These simple tips apply to most bolt rifles. Keep in mind they are all just observations and numerous tests to reduse harmonic frequencies in the barrel. I'm not an engineer or firearm professional.
