1:9" twist 22-250?

[Marlin Junky]

So, why not?

1:9" twist on a .22 bore scales to 1:12+" on a .30 bore and I'll have an assortment of copper patch from the tiniest lead-free, to bullets capable of taking meat doe, for example:

http://www.midwayusa.com/product/199027/sierra-gameking-bullets-22-caliber-224-diameter-65-grain-spitzer-boat-tail-box-of-100.

Assuming a good barrel, such as a Shilen from Brownells, what would be my velocity limitation on cast? I like the idea of shooting 60+ grain cast too, which will probably be easier to handle than castings from 225438, for example.

Thanks for the input,
MJ

P.S. Now I have a bunch of Re7 and am wondering how that powder will work for reduced loads in the 22-250. The only 22-250 I owned was back in the 70's when all I was doing was pushing 55 Sierras as fast as possible with H380.

[Bullshop]

I built a 22/250 with a 1/6.5" twist. I had no intention of shooting cast in it. It was made exclusively for 90gn Berger VLDs and it shot them very well.
I built a 224 Clark with a 1/9" twist but again it was intended on for the 69gn Sierra bthp and it shot them well at 4000 fps.
There are plenty of 223s with 1/9" twist that are shooting cast quite well. A 22/250 should at equal pressure to a 223 deliver higher velocity or equal velocity at lower pressure so should do well. I have a 22/250 that shoots cast extremely well but it is a 1/14" twist.

[Marlin Junky]

I have a 22/250 that shoots cast extremely well but it is a 1/14" twist.

Bullshop,

More details please. At what boolit length and/or weight does accuracy start to deteriorate from your 14" twist 22-250? I'm thinking there may be a compromise twist somewhere between 1:9" and 1:14".

I understand the 50'ish grain Sierra Varminters (that I'll probably be using the most) may start to come apart when launched from a 1:9" twist; however, I plan on throttling them back to 222 velocities if accuracy is possible with a 2/3 to 3/4 charge of Re7.

MJ

[Bullshop]

I have not tried to wring anything out to absolute conclusions. I am just trying a few things that work and staying with that.
A favorite load in the 1/14" twist 22/250 uses the NOE copy of the RCBS 55gn bore rider. Mine come in at 62gn ready to load with coww type alloy. The powder charge is 8gn of Alliant E-3. The E-3 powder shows up on a burn rate chart along side of Red Dot so is quite fast burning. I have not chronographed the load but in field use it is a simple matter to hit small targets to 200 yards with the rifle sighted about 2" high at 100 yards. I would guess about 1500 to 1600 fps MV.
I have another NOE mold for a similer type boolit but at about 74gn. That one will not shoot from the 1/14" twist but did shoot well from a 1/9".

[runfiverun]

just use 223 loads in your 250.
you get the same results.

[Marlin Junky]

Bullshop,

Thank you for the very useful information. Before I purchase a barrel, it would be nice to know if your 74 grain NOE would stabilize from a 1:12" twist.

Thanks again,
MJ

[Marlin Junky]

just use 223 loads in your 250.
you get the same results.

That's pretty much what I plan on doing with the fragile Sierras... major difference though is the amount of air in the case.

MJ

[btroj]

Why go faster than 1:12 if you don't bullets over 55 gr?
A 1:9 will stabilize a 69 Sierra. It will not generally shoot a 50 as well as a 1:12 will.
I have 2 AR15 set up for Highpower, they no have a 1:7 and shoot 80 Sierras very well.

I like to go slow as possible for them intended bullet.

[Marlin Junky]

Why go faster than 1:12 if you don't bullets over 55 gr?
A 1:9 will stabilize a 69 Sierra. It will not generally shoot a 50 as well as a 1:12 will.
I have 2 AR15 set up for Highpower, they no have a 1:7 and shoot 80 Sierras very well.

I like to go slow as possible for them intended bullet.

Actually, I kinda went overboard there for a minute 'cause the wife wants a lil' deer rifle; therefore, I was thinking 65 grain Sierra Gamekings too. In all reality, 45-55 grain copper patch and 60-80 grain (ready to fly weight) grooved/lubed will be fine.

MJ

[Bullshop]

I think what you would see with the 74gn NOE and a 1/12" twist is decent accuracy at close range but signs of bullets tipping on target. At anything beyond modest range they would likely just completely bug out and head for parts unkown. Maybe I am wrong and they wouldnt even work at 100 yards. I think 1/9" was the targeted twist for the design.

[Bullshop]

OH and by the way I shoot the 62gn NOE in my 22 Cooper. Out to 100 yards it is wounderfully accurate but you can most definately see tipping on target. The 22 Cooper has a 1/14" twist but is only capable of about 1800 fps max with that boolit. Beyond 100 yards all bets are off especially if its windy.

[btroj]

Sometimes a barrel needs to be set up for a narrow range of bullet weights. Velocity plays a role too.

I would decide what the primary projectile weight will be and go with a barrel set up for that.

[Bullshop]

Yup you got it right. The same boolit that shows signs of tipping at 100 yards from my 22 Cooper at 1800 fps MV shows no such signs of tipping from my 221 FB at 2500 fps MV with the same 1/14" twist.
Set yourself up right in the middle between too fast and too slow. Too fast a twist will limit velocity potential and too slow a twist will limit boolit weight/length. I guess there is just no way arround some kind of comprimise unless you can get an adjustable twist barrel.

[btroj]

Yep. Compromise means not bad at anything but not the best at anything either.

[Marlin Junky]

I think what you would see with the 74gn NOE and a 1/12" twist is decent accuracy at close range but signs of bullets tipping on target. At anything beyond modest range they would likely just completely bug out and head for parts unkown. Maybe I am wrong and they wouldnt even work at 100 yards. I think 1/9" was the targeted twist for the design.

Thanks Bullshop... I'll have to choose between a 1:9" and 1:10". I prefer the latter, but it'll cost me more.

MJ

[btroj]

A yes, the cost. That is a factor never to be ignored. Sometimes coatis the determining factor.

[Marlin Junky]

Will a 12" twist stabilize the 60-ish grain boolits like SAECO 221?

Someone brought a very nice Rem 700 in 22-250 to the range this morning to sell, but I passed on it because of the 14" twist.

MJ

[johnnybar]

Savage runs a 1:9 in the 22-250 varmit rigs I own. It will do fine until you get into the jacketed 70gr and up weights. If you know the exact bullet length and weight, I have a calculator somewhere that reports required twist.