i'm in the process of building a 7mm Mauser off of a new production M70 FWT. will be used as mainly a deer gun with the occasional Wyoming antelope thrown in. planning on using mostly 120-150 gr bullets, don't need anything heavier as i have a .358 Norma Mag for the big stuff. what is the ideal twist rate for this rig? thinking 24" Douglas Premium barrel, i also seem to recall reading something about a specfic reamer to use so it does not have excessive throat meant for the long 175's.

I believe that Mule Deer wrote in an article that he had a custom 7X57 built and told the gunsmith that he wanted it to shoot 140's and the gunsmith had it riffled in 1:11. It shot 140's very well but would not shoot 160's. I think that I would do it in the standard 1:9 or 1:9.5 and it would shoot anything.

Send a PM to Redneck. He built something similar for a member here, ( huntr, IIRC ) using the customer's reamer. Lee helped spec out the reamer. Heck, just get him to re-barrel.

LOL wish i could, but the laws on either side of the border make it too much of a headache...

I would use the standard 1-9. Accuracy will be fine even with 120's, and some of today's 7mm bullets in the 150-grain class do better with 1-9.

Sorry, I missed your location.

9"

My new 7x57 is 1-9", and shoots 140 gn Partitions very well.
I have two older ones that are 1-10", and they shoot the same bullet well. I doubt that I'll shoot anything heavier than the 140's.

I did mine with the 1 in 9 as well and it puts the 120gn GS HV into amazingly small spreads as it does with the 160gn Woodleigh.

Von Gruff.

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From the 7 x 57 in an 1895 Chilean Mauser...

What twist is needed to stabilize the Sierra 175 grain boattail ?


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Currently have three 7x57s with three different twists. 8.75", 9" and 10". All shoot 115gr to 160gr bullets with a good degree of accuracy and each prefer a different bullet weight and brand for exceptional accuracy.

I keep things simple.

7mm - 9
6 and 6.5mm - 8
30 - 10
338 - 10
358 - 12

Those will handle most any bullet w/o problems w/solid accuracy IME if you are not shooting bonafide benchrest.

I use 1~9 twist barrels on my 7X57's

1:8.66"

Dang double tap.

Factory twist for reference:

7 x 57mm - 1 in 8" . . . . . . . . . . .Ruger (present)
7 x 57mm - 1 in 8 1/2" . . . . . . . .Winchester 70 (post 64)
7 x 57mm - 1 in 8.7" . . . . . . . . . .FN
7 x 57mm - 1 in 8 3/4" . . . . . . . .Winchester 54, 70 (pre �64); Ruger 77
7 x 57mm - 1 in 9" . . . . . . . . . . .Mannlicher-Schoenauer; Thompson/Center Rifle
7 x 57mm - 1 in 9 1/4" . . . . . . . .Remington 700
7 x 57mm - 1 in 9 1/2" . . . . . . . .Ruger 1, 77 (old); Savage 110
7 x 57mm - 1 in 10" . . . . . . . . . .Winchester 70

geo