7-1 vs 9-1 twist

Typically, it's better to have too much twist vs not enough. A 7 twist will shoot some of the lighter weights as long as your not pushing them too fast.

Too much speed plus a fast twist means too many RPMs and rounds disintegrate in flight.

As for the 55s...

If you oly plan on shooting 55 or lower, go with the 9 twist. Is will shoot the smaller bullets, more efficiently.

The best twist, IMHO, for a 223 round is an 8. It's very versatile.
 
Thanks. The one I got in July is a 7-1. I've shot at 24 and killed 21 with it. The muzzle velocity is 3240 on the bullet. My buddy just put another one together for me and it's 9-1 so I guess I should be ok. Thanks for the replies.
 
I wouldn't buy a 1:7 unless I wanted to shoot heavy VLDs. Even my 1:10 will shoot 60 gr. Partitions very accurately.

I guess if they outlaw jacketed lead bullets you might have an advantage, though. That might be something to consider.

1:9 is a pretty sweet choice for something like predator hunting, IMO.
 
The 7-1 seems to do ok with the 55???? I have 1,000 rounds of the hornady 55 grains so I hate to do the switch. What would the 7-1 with 3240 and 55 grain do that would warrant me going heavier?
 
I a regular AR, not much. But a higher BC bullet may flatten your trajectory a bit. A 1-7 really shines in 2 aspects. A longer barrel for launching heavier bullets and getting the speed needed to maintain ballistics.

And in a military rifle. The steel core ammo is a bit longer, due to the less dense steel. So our M-4 are equipped with a 7 twist to stabilize the longer bullets.
 
ive heard from a few diff benchrest shooters that you get more accuracy with a just enough twist to stabilze the bullet. more twist isnt always conducive to being more accurate but not enough twist will surely give poor results.

IMO a 1x7 is complete overkill for anything lighter that 68gr. my 1x9 shoots the 68gr into very good groups.
 
Originally Posted By: SHamptonThe 7-1 seems to do ok with the 55???? I have 1,000 rounds of the hornady 55 grains so I hate to do the switch. What would the 7-1 with 3240 and 55 grain do that would warrant me going heavier?

7 twist is fine with 55 grainers. No need to go heavier for yotes inside of 300 yards. The 7 twist disintegrating bullets is a myth unless you're trying to push a 35-40 grainer to 4000 fps. You've killed 21 of 24 with this combo per your previous posts. I seem to remember something about not fixing things that aren't broken!
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Originally Posted By: Scoop1
7 twist is fine with 55 grainers. No need to go heavier for yotes inside of 300 yards. The 7 twist disintegrating bullets is a myth unless you're trying to push a 35-40 grainer to 4000 fps. You've killed 21 of 24 with this combo per your previous posts. I seem to remember something about not fixing things that aren't broken!
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There's your answer right there Hampton.

The 1:7 seems to be working for you just fine. The 1:9 will too.
 
I'm going to say my 1:8 was the most forgiving I have shot when it came to bullets. Although all of my barrel have like the high quality expensive ammo
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If you shoot a bullet in a 9" twist barrel at, say 2800 FPS, the bullet spins one revolution in 9" of distance. Is that correct?

So, if you shoot the same bullet in the same rifle, but the velocity is increased to 3000 FPS, does the bullet spin faster than one revolution in 9" of distance like it did at 2800 FPS?
 
Originally Posted By: Winny FanIf you shoot a bullet in a 9" twist barrel at, say 2800 FPS, the bullet spins one revolution in 9" of distance. Is that correct?

So, if you shoot the same bullet in the same rifle, but the velocity is increased to 3000 FPS, does the bullet spin faster than one revolution in 9" of distance like it did at 2800 FPS?

Yes to your first question. Bullet will always spin 1 time in 9 inches no matter what the velocity.
No to your second question. Bullet still spins 1 time every 9 inches no matter the velocity.
However it will travel the 9 inches faster thus spinning faster in time (rpm) with incressed velocity.
Hope that muddies things up a little more for you.
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Originally Posted By: Winny FanIf you shoot a bullet in a 9" twist barrel at, say 2800 FPS, the bullet spins one revolution in 9" of distance. Is that correct?

So, if you shoot the same bullet in the same rifle, but the velocity is increased to 3000 FPS, does the bullet spin faster than one revolution in 9" of distance like it did at 2800 FPS?

Nope, still only one full turn in 9"

It just covers the 9" quicker, therefore more RPM's.

Twist rate is the ratio of turns to horizontal distance traveled. RPM is turns over time.
 
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