I am building a new 22-250 for some long range target practice. I want to shoot heavy bullets (65-75 grains)out of it at 3200-3300 fps. Which twist rate would be optimal for this set up?

http://benchrest.com/sst/shilentwist.html

Looks like a 1-8, at least as far as Shilen is concerned.
- mike

For the long bullets like that, mho is correct. You'll want a 1:7 or 1:8. You might be able to get away with a slower twist like a 1:10 but it'd be touch and go would be my guess.

Does bullet speed affect twist? I assume that a faster bullet will get more RPM out of a cetain twist rate. Is it enough to matter?

I just read the Shilen link. How much does speed affect twist? Will the 500 fps difference between the 223 and 22-250 be engouh to change the required rate of twist in heavy bullets?

The 1:8 twist would be your best bet. Once I shoot out my barrel with the factory 1:14 twist it's going to be rebarreled to 1:8 to shoot heavier bullets too as well.

I barreled my 22-250 to 1:7 and it does very well with 75 and 80 g. bullets. There were some that said that the tight twist would preclude use of lighter bullets. So far I have shot 52 and 55 g. bullets out of it (just to deplete some loaded ammo I had). It shoots those very well too. 1:8 is probably fine, I sure wouldn't argue with a barrel maker, but I don't think you can go wrong with a 1:7

As Pet points out, with a twist rate, of 1 in 8 or 1 in 7, you pick up the ability to shoot the long target bullets quite well... what you give up is the ability to shoot some of the lighter bullets or the more fragile/explosive bullets....

It will just vaporize those...

I have a new Savage 12BVSS in 223, with a one in 9 twist....55 grain SPSX hornadys with an MV of 3200 fps virtually vaporized coming right out of the barrel....

If you want to shoot some of the lighter bullets, I'd go with the 1 in 8 over the one in 7.....

Pac Nor makes twists down to one in 5.5....

I know one guy who is having a 22/284 made with a one in 5.5 barrel just to see how many different bullet types he can vaporize in 22 caliber.....

With a 22.250 tho, actually a one in 10 or one in 9 will also stabilize the 75 and 80 grain bullets... as the cartridge developes enough velocity....

I am taking a 223 and reboring it to 22.250... It has a one in 8 twist on it....

Good luck..
cheers
seafire

I am considering the same thing. I have a Savage barrel with a 1:9" twist that I may rechamber to 22-250. I am wondering if the 1:9" would be adequate. I don't need to shoot really light bullets but it would be nice if I could shoot 55 grain slugs.

Most .22-250s come with a 1 in 14" barrel twist which won't do you any good above 55grs. I'd be thinking about a 1 in 8" twist for the heavier bullets. That'll probably fix you up nicely. Best wishes.

Cal - Montreal

quote:

Originally posted by elkhunter:
I am considering the same thing. I have a Savage barrel with a 1:9" twist that I may rechamber to 22-250. I am wondering if the 1:9" would be adequate. I don't need to shoot really light bullets but it would be nice if I could shoot 55 grain slugs.

Elkhunter:

Just keep away from bullets like the SPSX hornadys.....Sierras, Noslers, and Regular Speer and Hornadys work just fine... the 60 grainers will all work well....I love the 60 grain V Max!

Cheers
seafire

Contrary to what Cal says I've found the 1/14's to shoot the 60's and the 63's very very well.

The 63 Sierra is one of my all time fav's for accuracy and gaming ability.

The 60 Horns and the 60 Noz's shoot incredibly well also.


Just my 12 cents worth.

Mark D

Elkhunter, I don't think anyone ever your question about bullet speed. Yes, is the answer. You can partially make up for a slow twist with increased speed. The 22-250 being one of the fastest 22's out there is especially forgiving in this regard. However, for the longer bullets like the heavy Matchkings etc. you're still going to need a faster twist.

My 22-250 has a 1 in 14 twist and it shoots the 60 grain Hornady's (haven't tried V-Max). the 63 grain Sierra and the 70 grain Speer very well. I hope this barrel keeps shooting like it does for a long time but when it finally goes I want to rebarrel to 224 TTH with a 1 in 9 inch twist. Gotta try those 75 grain AMax bullets.

Sorry, I was playing the same mental game yesterday in regards to a 220Swift.

So what you guys are saying is that in a 22-250 (the Swift isn't that much faster) with 1-8 twist, 60-80 grain bullets (Partition, Matchkings, and TSX come to mind as ideal) will stabilize and good 40-55 grain bullets like Nosler BT's will hold together?

That probably just decided the end result of a Mauser sitting in my safe with a crap barrel!