Bullet weight versus Barrel Twist?

Ranger66Rick

Ranger66Rick

New member
I recently purchased a 243 win. Model 10 GXP3, it has a 1:9 1/4 twist. I was doing some reading on twist vs. weight and I was wondering would I be better off shooting something like 85-100 gr bullets, right now I have some 65gr hornady v-max reloads that shoot alright but haven't tried different bullets or powder charges. Most of my shooting will be done in the 300 yard mark (deer, coyote, g-hogs). I also have some 95gr Nosler Partitions that I haven't loaded yet and am earger to check them out. Anyone got a good load for the 95 partition with IMR 4350 powder?
 
You need a faster twist to stabalize LONGER bullets. The longer they are the faster the twist needs to be. Think of a top. A short fat top will stay up when spinning slow but a tall thin top will fall over unless it is turning very fast. Same thing with bullets. A fast twist will stabilize long bullets but it will also stabilize short ones too. Vice versa, a slow twist will stabilize short bullets but will not stabilize long ones. Vary your velocity on the 65 VMax's and I bet you'll find a keeper.
 
tonlocus hit it on the head - its length, not weight, that determines proper barrel twist.

The attache link is written by a lady who has a pretty good grasp on ballistics and rifling twist. Look in the "Interior Ballistics" Section and she has a very thorough discussion of bullet length versus rifle twist rates. - BCB

http://www.aeroballisticsonline.com/
 
True. But within a given caliber, isn't a LONGER bullet usually a HEAVIER bullet?

If you're shooting a rifle with a rate of twist much faster or slower than the "mid-range" twist, then you'll likely get the best results with heavier or lighter bullets respectively.
 
Yup longer will always be heavier given the same construction. It is the length not the weight that requires the twist though.

A form of exception is the Barnes all-copper X bullet. If you switch from the same weight jacketed/lead core bullet to a Barnes, it will be longer than the equivalent-weight lead core bullet because the copper is lighter than lead. Going from one X bullet to a heavier X bullet will of course increase length there too.
 
This is good stuff, I was under an impression that a higher ballistic coefficient required a faster twist. This may unravel why I had such a difference with the Noslers & Sierra bullets.

Btw welcome to the board Ranger66Rick. My 700 has a 1:9 & 1/8 twist, seems to like the 70 - 85 grain ammo. I had tried some of the Partitions before, but I was using 414. Now partitions might not win a match shoot but you'll probably find plenty of hunters that swear by them.
 
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Longer does generally equate to heavier in bullets.

About the only exception would be with some VLD bullets. They are very long but may not be the heaviest bullet in any given caliber. - BCB
 
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