22-250 AI 7 twist

[backyardsniper]

Guys I need a little basic knowledge here. I've got a fella wanting to trade me a 22-250 AI with a 7twist at 20" I'm very interested and I have long been wanting to try a fast twist 250 to run the heavy bullets at high speed so what I need to know from some guys that have experience with these is.
What kind of performance over the regular 250 can I expect?
Is a 7twist enough to stabilize the 88 eld and 90gr8 variety bullets, if so what powders should I look at to run in it. H4831/Rl22 burn rate?
What is the expected barrel life, I know its short but just a general idea. 800 to 1000ish?
It appears to be a nice handy set up. 20"M24 contour in a HS precision police style stock. He said he was getting 3550fps with 80gr eld using hybrid 100v. That sound reasonable?

 

[del2les]

I'm running 26" tubes with 1/8twist in my 22/250AI's, and I stabilize the 88/90 ok. While I have used a variety of powders through the years, currently, I am loading 7828SSC for added speed, and I can easily reach 3500fps with the 80's, but I am not sure about a 20inch. Even if you only get 3400fps with the 80's, that is plenty to shoot 1,000yds. I have used 80ELD and Berger to 1 mile, but the 88-90's perform better at those ranges

 

[backyardsniper]

Awesome. I should be able.to stabilize the 88 in a 20" 1/7 then. Maybe not max speed but I bet it'll be fast enough to impress a coyote or a whitetail

 

[hunter67wa]

I shot 75 eldm with 8 twist 22-250ai 20" with H414 and was in the mid 3300's. I can look up my load for you when I get home if you like.

Interesting though when I was ordering my barrel from Shilen i asked for a 7 twist and they called and inquired what I was shooting and at that time was straight 22-250 and they strongly suggested 8 twist cause of velocity. I don't know if to much velocity on fast twist is detrimental.

 

[jeffke]

I have a 7 twist 22-250 AI and its to fast to shoot any of those bullets. Im shooting a 70 grain berger target bullet at 3100 fps. I have to shoot the target bullet because of the thicker jacket and cant shoot any faster than 3100 any faster and they blow up 50 yrds out of the barrel. My barrel is a PAc-nor 28 inch 3 groove.

 

[johnnyk]

"My barrel is a PAc-nor 28 inch 3 groove."

I wonder if it's the 3G that's causing your issues. I have a .270 Allen Magnum, 30" Lilja, 8T, 3G and I read something about the 3G's ripping bullets. I talked with Kirby Allen and RoyinIdaho and they advised once the barrel gets a few rounds on it and rougher it tends to have a not so desired effect on the bullet jackets.
It has been recommended to my by KA to not shoot AccuBond LR in my rifle. He says they will not hold up to the speed and RPM's. I've never tried them in that rifle (I thought of secretly trying the newer 165gn, 270's!).
Not sure if this is the issue with yours, just "rang a bell".

 

[North Idaho Hunter]

20" xcaliber 6 groove 8 twist for my 22-250 Ai.

3900 w/40 grain Nosler ballistic tips & 4064
3100 with mild charge of 4831 & 70 grain soft point.
3000 with 75 grain eldm

I've never tried running up to pressure - just found accuracy first trip out with all the loads so I never tried going higher!

 

[AZShooter]

There is something that happens with a 3 groove and a fast twist. BUT bonded or monos can survive the trip once the throat gets rough.

My first experience with a 1 in 7 3 groove was with a 7 Rem mag. 180 Berger hunting VLDs were going 3050 fps. After a few hundred through the bore they began to have damaged jackets which caused radical divergence of up to 5 inches from POI at 100 yds. Switching to 180 target bullets with thicker jackets worked for another 100 rounds or so. Then they began to show signs of damage too.

Switching to 140 accubond or 140 TTSX solved the issue but BC was disappointingly low.

Lesson learned use just enough twist to stabilize a cup and core or use bonded or monos with a 3 groove!