300 Norma Magnum Twist Rate

[LukeM]

Hi all,

Was wondering if I could get some input from those who have any experience with 300NM. I am having one built, but cannot decide on the twist rate. I will primarily aim to shoot Berger 230/245 hybrid.

There's a lot of mixed opinions online - some say 1:8 so that you can use pretty much everything under the sun up to the 250 atip, but others say 1:9 is a lot less finnicky and easier to get good results with.

SG wise, the 245 LRHT is at 1.95 for the 8 twist, and 1.54 for the 9 twist (both @2850fps).

Has anybody got any personal experience with both options? I almost want to split the difference, but very few people seem to make 8.5 twist .30 blanks.

Cheers

Luke

 

[Edinburgh Rifles]

1:8
anything else is a waste!

no issues with any load development in both my 1:8" Normas with 200, 225, 230, 245 and 250 gr lead, and 200 and 208gr copper
if anything the copper should have been fussy but I stopped after the first three rounds went into the same hole!

you can't over stabilise any of these, but you can under stabilise with a lower velocity

 

[Malxwal]

I run 245gr Bergers through a 32" 8 twist, albeit a 300PRC anywhere between 2925 and 3150, seems to work.

 

[ruger7717]

i went with a 30'' Bartlein 9 twist shooting 230 ATIPS did the mile on a MOA target on my 3rd round

 

[provarmint]

I went 1/9 30" but I only shoot 212g, I've seen both 1/9 and 1/8 shoot the heavier bullets very well.

 

[LukeM]

That's a even split of owners between 8 and 9

 

[Malxwal]

That's a even split of owners between 8 and 9

Go 8 , run the big bullets !

 

[shoppe]

300prc, 30 inch barrel with 1 in 8 twist. 230A tips.
Great!!