I am putting together a 300WM and am wondering what is the best twist rate. I see 1-10 is the most common. I have a Rock 1-11 5R blank laying around and would like to use it. Would this be acceptable or would a 1-10 produce better results?
What weight bullets are you wanting to use? The 1:10 will be good up to the 190s and 210s, if you want to go heavier the 1:9 is good for the 240. The 1:11 will be good for lighter stuff, 150, 180 maybe...
Sierra recomend a 1:8 for the 240's but i have had fair luck shooting them in a 1:10 with a similar case as the WM. The 1:11 should be good for anything up to the 210's, but thats not 100% solid barrels can vary a little. Alot depends on the style of grooving the barrel is.
Was thinking of the 240 grains SMK also. For that George at GAP recommends the 1:9" twist. However, I have discovered the 208 AMAX, so I am sticking with the 1:10". Should be sufficient. Cheaper and easier to find (at least for now).
I shoot the 208's in my 1:11" twist just fine. If you go with heavier bullets, then you will need a faster twist. Your barrel will shoot the 208/210 weight bullets fine.