Why was the 35 whelen twist rate set at 1 in 16 when 375 bores are set at 1 in 12? Was it because they originally thought it would be used with lighter bullets? Would a 300 grain bullet stabilize in a 1 in 16 twist?

quote:

Originally posted by 376 steyr:
Why was the 35 whelen twist rate set at 1 in 16 when 375 bores are set at 1 in 12? Was it because they originally thought it would be used with lighter bullets? Would a 300 grain bullet stabilize in a 1 in 16 twist?

I tried the 310 grain Woodleigh round nose and they were very accurate although I only shot them at 100 yards.

I don't know why 1 in 16 was chosen. It is the equivalent of 1 in 13.7 in 30 calibre. A 1 in 14 equates to 1 in 12 in 30 calibre so that would have made sense.

A slow twist can make accuracy easier. I had quite a lot to with the 358 STA and a match grade 1 in 14 was used by several people. I had a switch barrel bench style gun based on Rem 700 action, Jewell trigger etc. and magnum bolt face. Compared 338 Winchester, 358 STA and the 375. Same barrel profiles and same maker. The 338 had the standard 1 in 10 and the 375 the 1 in 12 and the 358 the 1 in 14.

A 1 in 14 in 358 would equate to 1 in 13.2 in 338 and 1 in 14.6 in 375.

If you picked the most accurate load (at 100 yards) the 338, 358 and 375 were pretty much equal. However, if you compared average accuracy over a wide range of loads, powders and bullets the 358 was well in front and I put that down to the slower twist.