22-250 help

[Mthomas90]

Long winded story here...

I acquired a macks Brothers action with a brand new 9 twist crown ridge barrel works prefit on it. The original plan was just to use the action for a 6mm build but I decided I better try the 250. So, I got some redding dies, some once fired Win brass, and some 75 amaxs to try out. The first 5 shots out the barrel were about nickle size with 33.5 grains of h4350 with a slightly sticky bolt. I went up to 35.0 where the bolt got very hard to cam over. All of those loads were .025 off. I came to the conclusion that something is wrong with the chamber right away, but the more I thought about it I seriously doubt it's bad.
I finally got some time after a couple months of the first 20 shots to try again. I tried 35.0 and 35.3 h4350 again with the amaxs backed off .032. The bolt was not near as hard to break the case free but still more than I have ever had with anything else I have loaded for. Using a hornady comparator the case is gaining right at .010 from the sized brass I bought. Could that much expansion be causing false pressure and making the bolt hard to cam the case? I've been reloading for 10 years or so and have never had anything like this.

When I have some more time I'm going to bump the brass I have shot back a few thousandths and give them a try.

Open to any and all suggestions and if I missed anything valuable information I'll be glad to get it. I have high hopes for this action since it's smooth as glass.

Thank you,
Michael

 

[Mthomas90]

I should add the fired brass shows no signs of pressure.

 

[Adam in WI]

You had sticky bolt lift at 33.5 so you raised the charge 5%?

 

[Mthomas90]

No I went up in .3 steps and stopped at 35.0 with h4350 the first go. Today I tried 35.3 off another. 010, the bolt is manageable but still more than I've had in the past.

 

[Lone Hunter]

Once fired brass out of YOUR rifle or someone else’s?

 

[Clancy]

Load data for the 22-250 and H4350 is all over the map. I use the Sierra data and it is well above the others, but I can lift the bolt with one finger.

Seem like the once fired brass is the culprit to me.

 

[Mthomas90]

Once fired brass out of YOUR rifle or someone else’s?

Once fired and resized. Not from mine.

 

[Lone Hunter]

Most of the time when you have this problem it is from buying brass fired in someone else’s rifle. If you can buy some NEW brass buy it and I would bet your problems go away.
Also, you said it has a Prefit barrel on it. Have you or anyone checked the headspace? I run 2 6XC Prefits on a Remage . About the only reason I pick up range brass is to set my Annealer with or give it to someone who wants it because I had problems with a hard bolt or not being able to chamber.
How do you like the MacBros Action? Been considering one of them. Really like a lot of the features.

 

[Mthomas90]

Most of the time when you have this problem it is from buying brass fired in someone else’s rifle. If you can buy some NEW brass buy it and I would bet your problems go away.
Also, you said it has a Prefit barrel on it. Have you or anyone checked the headspace? I run 2 6XC Prefits on a Remage .

I'm thinking the brass is causing my issue too. I bought the once fired trying to save some money on this one thinking the barrel would probably end up on the shelf anyway.
The headspace was pretty tight when I got it, I adjusted just a little with very little change in what I have been seeing.

The bolt is not stiff to lift the entire cycle, just that last cam over to break the case free.

 

[Lone Hunter]

How do you like the Mack Brothers Action? I really like the features and price point. Haven’t handled any yet but have heard good things about them.
I edited my post and didn’t get this posted in time. My suggestion is to buy new brass and see if it cures your problem. If it doesn’t you have more brass but I believe it will cure your problem. If you can check headspace I would do that also.

 

[Coyotefurharvester]

How does the brass chamber and extract with a stripped bolt? Both fired and sized.

 

[Mthomas90]

How do you like the Mack Brothers Action? I really like the features and price point. Haven’t handled any yet but have heard good things about them.
I edited my post and didn’t get this posted in time. My suggestion is to buy new brass and see if it cures your problem. If it doesn’t you have more brass but I believe it will cure your problem. If you can check headspace I would do that also.

The limited experience I have with it so far I really like granted it's less than 30 rounds. It is super smooth. I don't have much experience with many other custom actions but I think it's about the cheapest custom out there?

 

[deadidarren]

Your primer edges still radius or are they very flat

 

[Gary in MD]

I agree with others, get some new brass and it will probably solve your problem. Hornady lists 37.2 grains of H4350 with their 75 grain bullets so I doubt that you are over pressure.
Can you post a picture of your fired brass showing the primer?

 

[DaveTooley]

Your problem
"some once fired Win brass"

 

[K22]

Once fired and resized. Not from mine.

I would strongly suspect this is a problem especially with a tapered and over bore case like the 22 250. Save yourself a lot of headaches, start with virgin cases.

 

[urbanrifleman]

Ten thou shoulder growth is a lot.

 

[Mthomas90]

I had someone measure some virgin win brass with a B comparator, it measured exactly the same as my resized once fired. Attached are pictures of my 'hot' 35.3 gr h4350 cases, a resized case, and my go gauge used to headspace.
Thanks for all the info, any more is greatly appreciated.

 

[AlNyhus]

Did you remove the primers prior to measuring?

 

[Mthomas90]

Did you remove the primers prior to measuring?

I did not.