22-250 ai

[Geno C.]

The thing about prs is the speed limit. At 3200, there are smaller rounds that will hit that. 22gt being one, with factory brass. They thing is feeding and ejecting. A 22br or brx would be sweet.
But, they don’t always behave with feeding and ejecting. With a 22-250ai, you can stack them in a mag and feeding and ejection should be a non problem. You can run a low node, that’s more forgiving. I’ve ran this chamber for a couple years and it is nice. This is the first with a 7 twist though. We shall see how it works out:

 

[SmartDonkey]

Any of you guys shoot a regular 22-250 with 90 grain bullets? I have a 1-7 and a few boxes of 90 grain Sierra MatchKing bullets. My loading manuals don't go to that heavy of a bullet- but found some "close" info online- but if anyone had a good starting point.

 

[702lineman]

See post number 8 on this thread. I use to use them. Did awesome if they didn't blow up

 

[David.C]

Any of you guys shoot a regular 22-250 with 90 grain bullets? I have a 1-7 and a few boxes of 90 grain Sierra MatchKing bullets. My loading manuals don't go to that heavy of a bullet- but found some "close" info online- but if anyone had a good starting point.

IMR 4831 34.5-36gish, work your way up

 

[AMG04]

Rifle:
Origin Action
20" Shilen, 1-7.5 twist with 4 groove ratchet rifling
KRG Bravo

To get started I partially formed cases with the Cream of Wheat method. Then I selected powders for sighters & pressure testing: H100v, Superformance, H4831sc, MRP, 4000-MR.

Bullet:
75gr Hornady ELD-M
OAL - 2.612" (0.060" Jump)

Sighters:
40.4gr of H100v
1. 3214 / 6. 3231
2. 3212 / 7. 3192
3. 3268 / 8. 3208
4. 3231 / 9. 3252
5. 3180 / 10. 3248 / Avg. 3224

Pressure Tests:
Superformance (41.0 - 44.6)
41.0 - 3022 43.0 - 3182
41.4 - 2970 43.4 - 3155
41.8 - 3069 43.8 - 3201
42.2 - 3103 44.2 - 3243
42.6 - 3098 44.6 - 3273

H4831sc (41.8 - 45.4)
41.8 - 3028 43.8 - 3173
42.2 - 2955 44.2 - 3170
42.6 - 3095 44.6 - 3240
43.0 - 3165 45.0 - 3344
43.4 - 3210 45.4 - 3344

MRP (42.8 - 46.4)
42.8 - 3028 44.8 - 3353
43.2 - 3164 45.2 - 3439
43.6 - 3286 45.6 - 3471
44.0 - 3267 46.0 - 3432
44.4 - 3382 46.4 - 3529

4000-MR (42.4 - 46.0)
42.4 - 3328 44.4 - 3472
42.8 - 3363 44.8 - 3483
43.2 - 3396 45.2 - 3528
43.6 - 3414 45.6 - DNF
44.0 - 3435 46.0 - DNF

Across the ten rounds fired, both Superformance and H4831sc shot less than an inch. With that, they were selected for the OCWs.

The fire formed R-P brass holds an average of 50.3gr of H2O.


OCW / Group Testing:
Superformance has a node between 43.6 and 44.4 and wants to run 3250 fps.

H4831sc shot well with 5 of 6 groups around 1/2" and has a node between 44.1 and 44.7. It also was running an average of 3250 fps.

 

[Geno C.]

Bullet used might help

 

[Varmint7]

I am shooting the 69 gr Matchkings and they shoot very well. I'm not shooting high velocity, but they are consistently less than .25" groups at 100. Im loading Varget with 36grs.

 

[NodakBarbarian]

Rifle:
Trued/blued Remington 700 action. 26” PVA barrel hand throated for 88 gr eld to allow seating bullet bearing surface just about neck shoulder junction. MPA hybrid chassis. TBAC Ultra 7 suppressor.

Lapua brass fire formed with 38.3 gr H4831 SC.

I tested H4350, H4831SC, RL23, and RL26. H4350 had really good speed but bad SD/ES. H4831SC was very consistent but slow. RL23 consistently performed the best across the board regarding SD/ES and grouping. RL26 wasn’t bad either but a bit slower and didn’t group as well.

Final load is 40.9 gr RL 23 @ 3175 FPS. 5-7SD. .3-.4 MOA 5 shot groups.

 

[Geno C.]

Rl26 produced some really crazy spikes in high temps for me

 

[Varmint7]

Rifle:
Trued/blued Remington 700 action. 26” PVA barrel hand throated for 88 gr eld to allow seating bullet bearing surface just about neck shoulder junction. MPA hybrid chassis. TBAC Ultra 7 suppressor.
View attachment 8066064

Lapua brass fire formed with 38.3 gr H4831 SC.

I tested H4350, H4831SC, RL23, and RL26. H4350 had really good speed but bad SD/ES. H4831SC was very consistent but slow. RL23 consistently performed the best across the board regarding SD/ES and grouping. RL26 wasn’t bad either but a bit slower and didn’t group as well.

Final load is 40.9 gr RL 23 @ 3175 FPS. 5-7SD. .3-.4 MOA 5 shot groups.

Nice set up!

 

[swamper2]

Not sure but it should not be a big deal to rechamber a standard 22-250 to a AI. Or is it possible?

 

[2/319th]

The AI 40 degree shoulder chamber is simply an alteration of the factory chamber, if done correctly, it will still shoot factory ammo, that fire forms to the AI dimensions.
Reloading will require an AI sizing die at some point, at least, in order to set the shoulder back.

 

[waspocrew]

Not sure but it should not be a big deal to rechamber a standard 22-250 to a AI. Or is it possible?

Yes, you can have it rechambered to 22-250 AI. The barrel will need to be set back slightly to accomplish this, as the AI is designed to have 0.004 crush fit with factory ammo.

Another consideration is your current twist rate - if you’re wanting more speed, AI is great. If wanting to step up to heavier projectiles, you’ll want to make sure your current twist rate can handle it.

 

[swamper2]

Yes, you can have it rechambered to 22-250 AI. The barrel will need to be set back slightly to accomplish this, as the AI is designed to have 0.004 crush fit with factory ammo.

Another consideration is your current twist rate - if you’re wanting more speed, AI is great. If wanting to step up to heavier projectiles, you’ll want to make sure your current twist rate can handle it.

I have a 1-8 twist. How much more speed will it achieve.

 

[waspocrew]

I have a 1-8 twist. How much more speed will it achieve..

You're probably looking at an extra 100-150 FPS. When I had my barrel chambered, I went right to the 22-250 AI, so I don't have any data to compare to the standard chamber.

For what it's worth, my 22" 1:8 twist barrel handles projectiles from 55 - 88 gr very well. RL-23 and the 88 gr ELDM are going at a comfy 3150 FPS.

 

[swamper2]

You're probably looking at an extra 100-150 FPS. When I had my barrel chambered, I went right to the 22-250 AI, so I don't have any data to compare to the standard chamber.

For what it's worth, my 22" 1:8 twist barrel handles projectiles from 55 - 88 gr very well. RL-23 and the 88 gr ELDM at going at a comfy 3150 FPS.

Nice numbers. thanks

 

[AMG04]

Settled on a few loads for my 20" 22-250AI.

Low Cost Plinking:
75gr Hornady ELD-M
OAL - 2.612"
44.0gr - Superformance
3250 Avg. FPS

Long Rang Steel:
90gr Sierra Match King
OAL - 2.572"
41.0gr - H4831sc
3000 Avg. FPS

Hunting:
77gr Barnes LRX
OAL - 2.664"
42.3gr - H4831sc
3140 Avg. FPS

Fireforming:
55gr Nosler BT
OAL - 2.454"
38.0gr - H380
UKN Avg. FPS (no crono that day)

 

[waspocrew]

Braved the snow and rain today to get a little more trigger time in with the 22-250 AI. I'm currently at 766 rounds on this barrel and it's still shooting well. I have some more rounds loaded with the 75 Scirocco and 80 gr ELDM that I'll be testing out shortly.

77 TMK
41.1 gr RL-23
Fed 210
Lapua 1x brass
CBTO: 2.208 (0.020" off lands)

3345.7 Avg with SD of 6.8 per Garmin (5 shots) with a nice cluster at 100 yards. Might be able to tighten it up a bit with some nicer weather.