Rate of twist??

[Supermag]

Barnes sent me the reloading data for the .270WSM. I told them I have a Savage 16FCSS and was looking to reload the 140 gr TSX. They said that they recommend around 110gr TSXs for 1 in 11" twist barrels. 140gr TSX bullets might not stabalize in my barrel.

Can anyone explain this to me? Is that just the TSX? Is that due to the length of them, or what? I shot 130gr and 140 gr factory loads and they were fine.

I want to use a sturdy bullet like the TSX and be able to use the .270 WSM for deer, elk, moose and black bear.

Any comments????

[PoppaW]

You say you shot some 130 and 140 factory. Was this with x bullets? If Barnes says your twist is wrong, they may be right. One way to find out though is to shoot some.

[Rusty P. Bucket]

Here is a rifle twist calculator for you:

http://kwk.us/twist.html

Whether or not a projectile stabilizes or not is a function of velocity and projectile length. Longer, heavier projectiles generally need a faster twist on them than do shorter ones given similar velocities.

These formulas are not cast in stone; your individual gun may shoot a variety of weights equally well.

[raised by wolves]

Every gun will shoot a different way. Heavy, or bullets that are long in comparison to their calibre, should be used in rifles with a faster rate of twist, lighter bullets can have a slower rate of twist.

It will not make much difference on a hunting rifle. It really only makes a difference in long range, bench rest or tactical shooting.

My 308 target rifle will drop anything from 150 to 180 grain into the same holes at targets within 300 metres. The variation is only noticable, and becomes much more apparent with each additional 100 metre range. Ideally this rifle is intended for 140-160 grain at the longer ranges.

[Skinnydipper]

I shoot the Barnes 140 grain TSX out of the exact same gun and caliber with no apparent difficulty (3/4" groups at 100).