22-250AI question

[bado1]

Hi All,
Happy Independence Day!
I recently had my 22-250 reamed to AI. Did some successful fire forming and have begun working up a loads with the newly formed brass. Upon firing the AI round and inspecting the fired case I notice that the case mouth is out of round on one side of the starting loads and out of round more so on the "hotter" loads.
All cases were FL re-sized, trimmed, annealed, etc. prior to fire forming ( I did not trim the newly fire formed case when I reloaded them and just neck re-sized them with a Lee collet die). I also compared the newly fire formed cases and they too are out of round but not as bad (hardly noticeable) as the AI cases are once fired. Is the new chamber not cut correctly? What is causing this? While fire forming to AI the fire forming loads are very accurate (as accurate as the rifle ever was). Thanks for your in put.

Dean

[Gabe221]

Sold my 22-250 went to 22 BR, seems more accurate. Wish I could help.

[Bill K]

I would make a cast of your chamber and see how the cast looks and measures. Bill K

[Bayou City Boy]

The flat spot on the case neck could be a result of extracting the cartridge and it hitting the inside of the receiver just out of the chamber on the way out. AI cartridges, due to their straight case configuration with the sharper shoulder, slap harder to the right than a normal cartridge when extracted.

Completely extract a fired cartridge slowly with a finger on it to keep it from slapping to the right as normally occurs due to the ejector spring location, and see what happens.

-BCB

[kenbro]

Are the necks oval, or flattened?
Ken.

[Tim Anderson]

I'm with BCB on this, extraction is the cause.

[Alycidon]

Originally Posted by Gabe221

Sold my 22-250 went to 22 BR, seems more accurate. Wish I could help.

So did a good friend of mine, his was a 22.250AI, he shot the barrel out trying to make it shoot decently, as a 22BR it now shoots in the .2s.

A

[TinMan]

+1 on an extraction/ejection issue. You didn't mention action was used on the rifle, but if it a Remington or some other action with the spring loaded ejector, you might cut the ejector spring back a coil or two until you don't get the mouth/neck flattening.

[bado1]

Thank you for the quick replies and great input!
I thought of the extractor issue as well. The rifle is a Remmy 788. I dont like the spent cases to fall on the ground so i usually extract slow with my hand over bolt so the case doesn't come flying out so the extraction process is pretty gentle. I don't think that is the cause but i will be extra careful next time and rule that out. The cases are not oval. More like flattened on one side and a couple of the warmer loads even show flattening in two or three places around the case mouth. One of my thoughts is could the case necks need turning? I put a call in to the smith that did the work so I will see what he has to say as well.

As to going to a 22BR... This rifle/caliber combo is supremely accurate (it was as a 22-250 anyway. Still need to see what it will do as an AI.) The throat was getting a bit long after god only knows how many thousands of rounds I put through it over the years (+/- 3500?) and it still shot like a laser if I used a longer bullet and seated them out to the lands. The pain was that they exceeded mag length and the 788 does not lend well to single feeding so I decided to have the barrel scoped and set back if all looked good and decided to go AI. I have hundreds of 22-250 cases and .224 bullets so it seemed the logical thing to do. Hopefully, it will be as accurate as an AI and not nearly as much case trimming. Thanks!

Dean

[Bayou City Boy]

By the time the brass hits your hand, the damage has been done.

-BCB