22-250 witha 8" twist

[north of 53]

22-250 witha 8\" twist

Well I went and did it. I took my old 788 22-250 into a smith to see what we could do about the barrel. I was not sure if it could be just set back a little or would need to be replaced. Well he took one look at it and said he has not seen many barrels that had been shot out more than this one. I told him I had thought that might be the case as it is over 30 years old and has over 3000 rounds through it, he thought closer to 5000 and he could be right.
So now it is getting a new 28" barrel with a 22-250 A.I. chamber and a 8" twist. I am planing on shooting some of the Berger 75& 80 grain VLD bullets. I was wondering if anyone has tried them in a 22-250 A.I. If they have, what kind of velocity and accuracy they got out of them.
I would also be interested if anyone can tell what happens if I was to shoot some 50 and 55 grain bullets in a 8-1 do they hold together if you push them up over 36 or 37 hundred.
I know there are many other ways I could have gone with this gun and even got a new gun cheaper but then it would not have been my 22-250 from my youth. It is a bit of a project that should be back to me in about 6 weeks.
As always I thank you in advance for your input.

 

[B Jordan]

Re: 22-250 witha 8\" twist

i am pretty sure a 22-250ai wont feed thru the clip without some modification i ended up messing up a clip on a 223 ackly in a 788 trying to get them to feed
you might think about a 22-243 (standard)if you want more speed than a 22-250 i built one but it was on the longer action 788 it worked fine i think it was a 7mm-08 originally

 

[north of 53]

Re: 22-250 witha 8\" twist

As far as what will fed through the clip I couldn't care less. For the kind of shooting i will be doing I will never use it. I have not used the clip on this gun in years. I allready have the project moving along as a 22-250 A.I.with a 8" twist. I was just wondering a little about what I might expect when I start shooting it. I am notlooking for what some one else might think would have been a better way to go. If it was not a 22-250 I would not feel right shooting this gun.
Some people don't feel right driving anything but a Ford so thats what they drive. Even if others are sure a Dodge is better. I am building a 22-250 because that's what feel right for me.

 

[Wild_Bill]

Re: 22-250 witha 8\" twist

Hi North i have a 22-250AI and have a 6.8 twist on it the barrel was originaly chambered in 223 so i could get a difinative velocity test diference after 150 rounds were fired we rechambered it to 2-250AI and re tested every projectile. i shot from 5gr BlitzKings to 90gr Sierra MatchKings through it the twist was fine for all projectiles in 223 but a tad har on the 55gr at max velocity on the 22-20AI. The 8 wist is much better for the 22-250AI and will shoot a 5gr Blitzking very well and you will not have any trouble with them staying togethor as long as yu dont try to push them past 4K. The 22-20AI in the 8 twist should also stabalise the new 90gr Sierra quite well so give it a go the fast twist on the barrel was to harsh on the 90's in 22-250AI but was fine with the other MatchKings. Be aware thet the 8 twist wil be very hard on the A Max's and Bergers because they have very thin jackets if you are et on using them get a 9 twist or you will blow them up in mid air. I blew the 75gr A Max'x up in the 6.8 twist when it was 223 so i did not try them in 22-250AI they would have never held togethor.

Cheers Bill

 

[Stormrider]

Re: 22-250 witha 8\" twist

I can't speak to the Berget bullets at high velocity. I've shot Nosler 40g bt's to better than 4500 f/s in one of my 22 CHeetah's. Shot less than moa too.

 

[ol mike]

Re: 22-250 witha 8\" twist

North of 53 ,-welcome !!

I know what you mean about keeping a rifle the same ,i have a 25-06 that i've had since 1980.A friend recommended i make it a 257stw -it wouldn't be the 25-06 i've had for most of my life.
The 55gr bullets will do ok at high speed twist but the big 75gr a-max and berger vlds will spoil you.
There is a good bit of data out there -start w/full house 22-250 loads.
You'll probably get around 3200ish out of the big bullets.
You're old sweetheart 22-250 is going to be a longrange monster w/the AI + fast twist custom barrel.You'll be glad you didn't get another rifle once you send a few bullets down a custom barrel.-Best to you --Mike

 

[Fiftydriver]

Re: 22-250 witha 8\" twist

I have found that number of rifling has been more important than actual twist rate when getting the heavy Berger bullets to stay together.

All has to to with bullet baring surface compression. Make sure the barrel your getting is not a 3 groove design. A 5 groove is better and a 6 groove would be the best.

The fewer the lands in the rifling, on average, the wider the lands. This is what causes the problem. Make sure your getting a thin landed 5 or 6 groove barrel or you will tear the Bergers apart no matter what velocity you are driving them to in a 3 groove barrel.

Kirby Allen(50)

 

[Guest]

Re: 22-250 witha 8\" twist

[ QUOTE ]
I have found that number of rifling has been more important than actual twist rate when getting the heavy Berger bullets to stay together.

All has to to with bullet baring surface compression. Make sure the barrel your getting is not a 3 groove design. A 5 groove is better and a 6 groove would be the best.

The fewer the lands in the rifling, on average, the wider the lands. This is what causes the problem. Make sure your getting a thin landed 5 or 6 groove barrel or you will tear the Bergers apart no matter what velocity you are driving them to in a 3 groove barrel.

Kirby Allen(50)

[/ QUOTE ]

Kirby, I was thinking of 105 Bergers in my in my 6x22-250. Are you saying that is no-no for the Lilja 3 groove?? My 107SRA's are running 2930-2950. Jim

 

[Varmint Hunter]

Re: 22-250 witha 8\" twist

Kirby,

Isn't it true that the lands on a three groove barrel are generally taller (engrave deeper)than that of 5 and 6 groove tubes? If so, this would likely be the cause of jacket integrity failure caused by the 3 groove tubes; wouldn't it?

 

[Fiftydriver]

Re: 22-250 witha 8\" twist

Jim,

Your 107s are shooting so well because of their relatively heavy jackets for a match type bullet.

In your 6-250, I would be suprised if you see a problem with the Berger or A-Max coming apart in the 3 groove. I have found the velocity limit where this issue comes into play is generally around 3200 fps with 3 groove barrels. If you keep velocity under that, no problem at all, over that and you generally get accuracy loss at best and total bullet failure at worst.

Your 6-250 will not be able to safely drive a 105 gr bullet to anywhere near 3200 fps.

On the other hand, the round in question, a 22-250 AI loaded with 75 to 80 gr bullets will certainly be able to reach this level of velocity. And that is why I made the recommendation. If it were a standard 22-250 I would say not as big of a deal but he will get an extra 100 to 150 fps out of the AI version and that will put him into the velocity range where there could be problems.

If he were shooting sierra bullets, there would more then likely not be a problem either because of the heavier jackets.

Kirby Allen(50)

 

[Fiftydriver]

Re: 22-250 witha 8\" twist

VH,

I can not say if the 3 groove has deeper grooves or not. I have never asked Dan Lilja about that. If they do that would certainly effect this in some way.

TO that point however, I have tested this theory in my Allen Magnums extensively with many different rifling designs. In the Lilja 3 groove barrels I get issues with some of the really heavy Wildcat Bullets in fast twist barrels so I tested some Rock 5R barrels. THey were even worse then the Lilja at tearing apart bullets. This example was with the 7mm AM shooting 200 gr ULD RBBTs built on J4 jackets.

I had Rock barrels redesign the 5R to a very thin land design. Roughly 1/3 of its original land width with no change to depth of groove and the problem totally went way. Even more, I was able to increase velocity nearly 100 fps with no bullet failures to this point.

So that tells me its more to do with baring surface compression percentage then anything else.

Still, if the 3 groove has deeper grooves, that would not help any with the thin jacketed match bullets.

Good point!!

Kirby Allen(50)

 

[jes10x1]

Re: 22-250 witha 8\" twist

Pardon me for starting in the middle of a discussion, but just found the site and have a question touching on what you gents are discussing:

I have the savage 12 22-250. I've ordered a 30" heavy barrel 1:9 twist to be chambered in 22-250 Ackley Improved. My goal is two fold:
1.Find a good shooting combination for 1000 yard competition that is easy on the shoulder and
2. have a long range varmit gun.
I intend to try to use the 75 A-Max for both. It appears the max rotational speed of the bullet and MV should match up pretty well. With the longer barrel, I'm hoping to be able to use all the AI capacity and use slower powders.
Does anyone have any load experience in this realm?