450Bushmaster.net

Hello I am starting a 450bm build from a savage 12fv and found a couple nice guns on here. I'm just curious on how you determined your barrel length and twist rate I've seen 1/16 and 1/24.

If you read through the forums the general consensus is you gain little in this barrel beyond 20" due to fast powders used. My 20" only gets me about 80 to 125fps depending on load over a 16" barrel.

As far as twist goes it depends on what bullet weights you plan on shooting. From personal experience the standard 1/24 seems to work well with the 200-250 range of bullets. Many seem to think the 1/32 is better for stretching the bullet range down into the 180gr range. Search the forums and you will get a lot of information and then make your decision.

Mallard1123-

More than three years ago I wrote some long posts about selection of twist rate in this thread: BARREL LENGTH AND TWIST RATES DISCUSSION

I haven't gotten any smarter or learned a whole lot since then on the subject, so have a look at some old stuff. Come back with any questions and I'll try to answer them.

One of my bolt rifles has a 1-in-16" twist, the other 1-in-24". The former was not a particular selection; the barrel cam with that twist. I did select the 1-in-24" twist fore the barrel on my 450B heavy rest rifle. It was what the factory AR barrels at the time were using, and I wanted to be sure any data I generated would be useful.
--Bob

Awesome thanks for the replies I tried searching for other threads but didn't get a lot of results.