twist rate on a pre64 m70 300H&H

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14 January 2010, 03:37

perry

twist rate on a pre64 m70 300H&H

Anyone have any idea before I use the cleaning rod to find out.

Thanks

perry

14 January 2010, 03:48

RaySendero

quote:
Originally posted by perry:
Anyone have any idea before I use the cleaning rod to find out.

Thanks

perry

Perry,

My guess would be 1 in 10".

14 January 2010, 04:29

dedseven

I have photocopies of in-house Winchester drawings showing Maximum cartridge/Minimum chamber dimensions for several caliber/model combinations. The one for the 300 H&H model 70 is dated Jan. 23, 193x (can't read the last digit) with revisions in '38, '54, '62, and '63, none of which refer to twist rate. It says the rifling form is 4 grooves, each .176" wide with a twist rate of 1 in 10". It seems it's pretty safe to say yours is a 1 in 10 unless something out of the ordinary happened. The only sure way to know about your barrel is to measure it.

16 January 2010, 06:55

tsibindi

Perry:

Per Roger Rule's book "The Rifleman's Rifle" the twist rate for the 300H&H is: One in ten.