Fast twist 22-250

[scott/r]

Something I've had sitting in the back of my mind for a while is building a 7 twist 22-250. My thinking is that with a 30" barrel, 90grn projectiles and the larger cases, it would have to result in good enough speeds to be interesting at the shorter ranges. I'm gathering this would burn barrels pretty quick, but how much I don't know.
I haven't been around fullbore shooting long enough to know if this has been tried before or even if I'm just bored and thinking to much.
What's your thoughts?

[macguru]

One of our older club members had what i think was an 8 twist 22-250 Ackley Improved firing 80grain projectiles at high velocities. It shot really, really well and could keep up to our current sixes (dasher etc) from what i remember... Barrel life was probably in line with the 6x47 lapua or maybe a bit worse. If the 90gr bullets do not work you can always go back to the 80-82gr ones.
but look at:
http://6mmbr.websitetoolbox.com/post/22 ... le-2466907

[Malcolm Hill]

One of our members tried a 22.250 with a 1 in 8 barrel a few years ago when there was only the Sierra and Amax 80 grainers available. Both shot very well but the Amax jackets didn't like the rotational speeds once velocity went over 3300 fps. The projectiles would come apart about 50 metres out from the muzzle at times and never get to the target. The Sierra's didn't have the problem due to thicker jackets and shot very well. There is a much wider choice of projectiles around now with the 90 grain offerings as well so it would be interesting to get them cranked up (which you can't do out of the 223 case) for some fairly tidy ballistic figures. Will be interesting to hear how it goes. Regards Malcolm.

[Frank Green]

Even at .223 velocities bullet failure rate can be very with the 90gr. bullets. It is a very common problem that I hear. I personally don't shot any of the bullets. At .223 velocities I recommend a 1-6.5 twist. Twist rate calcs come out to 6.8min. for those.

For a .22-250 I would go with a 1-7 twist.

To help fight bullet failure rate I would use a standard .2190" bore size (not a tight bore at .2180") and I would want the grooves at .2245". I would also prefer the 5R style rifling so the lands don't directly oppose one another as this will help fight distorting the bullet/upsetting the jacket more vs. a even groove barrel. We do this for a custom AR15 match rifle builder over here and he has pretty good luck with them and fighting the bullet failure problem and the accuracy is excellent. He builds match AR15's for across the course shooters. Guys shooting the 90gr. bullets the guns are pretty much being set up as a dedicated long range match or service rifle when based on a AR15 platform because the throat of the chamber gets so long to seat the bullets out so your not sucking up the case capacity. When that happens the rounds won't feed from a magazine.

Also keep in mind at the higher velocities of the .22-250 your going to be increasing the rpm of the bullet as well which has been mentioned previously.

As previously suggested if the 90's are a problem in any way you can always drop back to the 80gr. bullets.

Later, Frank
Bartlein Barrels

[Brad Y]

I would suggest a 22brx or dasher over the 250, I used to run a 22brx 10 twist for short range and varmints. it shot really well, and a straight 22br with a 7 twist and 90gr bullets didn't do that great. Possibly an average barrel, but once rechambered to a 223 it shot fine.

[scott/r]

Thanks for your replies guys. I'm not sure if you guys have talked me into it or scared me off. haha.

[Matt P]

Back in the very beginning of F Class when we had only one class, the 22-250 and the AI version were the calibers to beat, a few of the down falls were barrel life and the other was being able to put a bullet down the spotter peg and not do any damage to the peg which normally resulted in a miss
Matt P

[DenisA]

G'day Scott. The first thing that comes to my mind when you say "22-250 at the shorter ranges" are the QRA energy and velocity restrictions. There is a reference specifically to 22-250's in it.

Bullets of up to 145 grains weight are restricted by the maximum velocity limit even though they do not generate anything near the maximum energy limit, whilst bullets beyond that weight are restricted by individual velocity limits. This means that small calibre high velocity hunting rounds, like the 22/250 for example, would not be permitted when loaded to factory velocities or faster.

http://www.qldrifle.com/images/updates/ ... %20WEB.pdf

Defeats the purpose these days.

[scott/r]

That's a good call Denis. I would think that you would be be pushing the limits of the restrictions just as you came to the potential of the caliber. Maybe I'll have to have another chat with you about the 6br.

[macguru]

Yeah you would be over with a 22/250 .... the 6x47 is OK (3200) but there are bigger sixes that would not be. no one uses them anyway. (http://www.6mmbr.com/gunweek019.html)

If you specifically wanted a 22 for the shorts/medium because of projectile availability, i have seen a 22BR get great results. I am thinking a 22BRX or similar would be under that limit with 80gr as well.
(http://www.6mmbr.com/22BR.html)

[BRETT B]

Back in the very beginning of F Class when we had only one class, the 22-250 and the AI version were the calibers to beat, a few of the down falls were barrel life and the other was being able to put a bullet down the spotter peg and not do any damage to the peg which normally resulted in a miss
Matt P

I won my First Queens in 2001 using a 22-250 and 80gn bullets. It was extremely accurate and easy to tune.

33 gns of 2209 and 80 gn Sierra gave me around 3250 fps. I also had a 22-250 AI but found accuracy not as good at 3400fps with 80 gn bullets.

With the larger selection of bullets now and Lapua making brass I have actually been considering doing another one for local prize meets ..