22-250AI 7 Twist barrel

[Seddo]

Hi guys,

I had Lilja profile me up a 7 twist 22 cal barrel for a 22-250AI. I sent it off to a local gunsmith with my armours kit and barrel extension and got it back last week. There was a small issue with the profile job, Dan said it was most likely due to how it was polished as the profile had a cylinder. I had to put the barrel in the lathe and take a few thou off the muzzle end of the cylinder section. Its still a little tight so i have to do it somemore.




I took it to the range today to test it with some 50gr Federal factory ammo. I ended up firign 6 shots before i ran out of time. The surprise was 1 case seperated just below the shoulder which is the first time its happened to me.


Here are some formed cases (uncleaned) with a 90gr berger and 80gr amax in them with a regular 22-250 case for comparison.



Now that i know it works i will start fireforming the Lapua cases while i wait for the redding FL comp dies to turn up.

[Archaos]

Nice mate,

Glad to see another custom up and running. I am still waiting on the .223 conversion to come along. I'm not up on the 22-250, what's the benifit of going AI vs normal (pro's and con's), how will barrel life be effected, what's the increase in case capacity and how much increase in velocity.

I really need a bunny and fox calibre for mine, that's what the .223 would be for, turning little pests into red streaks of paste with my 308 does the job in controlling them but the a little too much in the destructive power.

[Seddo]

The benefits of the AI are velocity and lack of case stretching.

22-250 with 80gr 3000fps
22-250AI with 80gr 3300fps

The difference in max book loads with 2213sc is 2.3gr going by the sierra manual.

I had an issue feeding the 50gr factory rounds from the mag, the soft point was catching on extension or barrel. The 80's dummy rounds fed from the mag just fine

[Orkan]

I'm curious, how are you getting the 22-250 to eject reliably?

Without modification, they seem to come out and just barely flop out or fall back into the action. I bet the AI front end is just wide enough to give it good ejection.

On a regular 22-250, the shoulder tapers too much and releases all of the ejector tension before the case leaves the barrel extension. So it doesn't pop out.

[Seddo]

Orkan,

I kept my hand over the ejection port so i never really tested ejection, i also didnt have the spacer in it so ejection isnt 100% reliable without that in there. I am hoping to take some 80gr loads to the range on the weekend so i will see how it ejects then. If i can i will take a video of it.

[Archaos]

Hay Seddo, sort of the same subject, I was out with a mates 22-250 today having a play (no its just a Ruger) and I had 2 boxes of factory Winchester (Crapchester) ammo and out of the 40 rounds I would say nearly 30 of them split the necks, now these were all factory rounds. My mate said it always happens. I was concerned as failing cases isn't something that always happens. Is it just the Winchester stuff you have had issues with. I will get him to send me some pics and I will link them up. His rifle isn't even that old.... He should just buy a DTA

[Orkan]

Perhaps a wide neck chamber?

[Shooter Dan]

.... He should just buy a DTA

good suggestion! a 3/4 bust rate is pretty miserable--even if it's just the win...

[Seddo]

Archaos,
That's a bad strike rate for sure. I had the same issue years ago with some 222R ammo in my cadet. 80-90% of them split throu the neck into the shoulder. A few years later I was told of a bad batch of brass that was the problem. It's pretty sad when that happens with Winchester ammo.

[Seddo]

I fired 40 rounds through my 22-250AI barrel today. I used 2213SC & 2217 and had velocities ranging from 2600 to 2800fps which is fine for a fireforming load. Most of them were moa or better which was good considering it was bloody windy today and at that speed it was slower tham my 223.

Of the 40 rounds i fired, 37 ejected positively, 2 hit my hand and didnt get thrown clear and 1 was a FTE.

I will load up the remainder of the lapua cases adn blow them off next weekend and then start workign up a load with 80 and 90gr projies.