Rate of Twist on Mosin Nagant?

[rockstar.esq]

So does anybody know for sure what the twist rate is on the Mosin Nagant?

A quick follow up question would be what is the twist rate on the SKS and AK series?

A cursory check seems to indicate that the SKS and AK have slightly different specs for twist rates which is odd considering they use the same cartridge. I once read that the 7.62x39 was speced with the same twist rate as the much much older 7.62x54R partly due to Russian economist thinking. I've yet to find significant evidence to prove it either way so I'm asking THR for some good information.

 

[Mr White]

Rifling is 4 groove, right hand, 1 in 9 1/2" (24.1 cm.) twist for all models except the M28/30 which is a 1 in 10" (25.4 cm.) twist.

Quoted from 7.62x54r.net

I wonder if that 1/2" slower twist is what gives the 28/30s their rep as the most accurate MN.

7.62x54r.net is a great page for all kinds of info on MNs.

 

[rockstar.esq]

Thanks Mr. White, it appears that at least some SKS /AK series guns are rifled with EXACTLY the same twist rate, groove diameter etc! Lending credence to the aforementioned culprit of inaccuracy in AK's in particular.

 

[slzy]

what rate did the ppsh 41 have?

 

[Hoppy590]

for those of you who only speek Mosin. thats 10 line in .33 Arshin