Fire-forming and Concentricity

yountg

New member
If I neck-turn new brass and fire them in a very good chamber, shouldn't the fire-formed brass then be concentric (at least on the outside)?
 
It will be as concentric as the chamber is. If you're checking the necks for runout after firing, make sure that the case is extracted and ejected easily. A strong ejector can slap the neck against the receiver and give neck readings that are a fake out. Obviously, this depends on the ejector, case length, port size, etc, etc.

Good shootin' :) -Al
 
It will be as concentric as the chamber is. If you're checking the necks for runout after firing, make sure that the case is extracted and ejected easily. A strong ejector can slap the neck against the receiver and give neck readings that are a fake out. Obviously, this depends on the ejector, case length, port size, etc, etc.

Good shootin' :) -Al
Thanks! I ask because I just bought a "tight neck" 222. I FL sized some cases that were once fired in a different rifle which should make the cases concentric on the outside. I then neck-turned the cases because I had to....the cases also had inconsistent neck thickness. I believe that the case necks are now non-concentric. I am hoping that the new rifle has a good chamber. I think that in the future, I will be better off turning new cases for it (less steps).
 
Thanks! I ask because I just bought a "tight neck" 222. I FL sized some cases that were once fired in a different rifle which should make the cases concentric on the outside. I then neck-turned the cases because I had to....the cases also had inconsistent neck thickness. I believe that the case necks are now non-concentric. I am hoping that the new rifle has a good chamber. I think that in the future, I will be better off turning new cases for it (less steps).
That's not a good idea. Once cases are fired in another rifle, they belong with the other rifle. I know 4 guys, that fired the cases in another rifle. And the bolt was jammed up. Yep, all were 6PPC. But, the jam up was not too bad. All 4 broke the bolt handle off the bolt. I think only one could get the bolt loose after. The other 3 had to find a gunsmith.
There is an exception to that rule. If Dwight Scott did the chamber job with his new reamer.....I have been lucky. 4 different rifles and could swap the brass. 22 barrels I think. Good luck.
 
That's not a good idea. Once cases are fired in another rifle, they belong with the other rifle. I know 4 guys, that fired the cases in another rifle. And the bolt was jammed up. Yep, all were 6PPC. But, the jam up was not too bad. All 4 broke the bolt handle off the bolt. I think only one could get the bolt loose after. The other 3 had to find a gunsmith.
There is an exception to that rule. If Dwight Scott did the chamber job with his new reamer.....I have been lucky. 4 different rifles and could swap the brass. 22 barrels I think. Good luck.
Doesn't FL sizing take care of the fact that it was fired in a different rifle?
 
How do companies that reload used brass make sure that it will work in all rifles?
THEY LOAD TO sammi specs...6PPC IS NOT A SAMMI CARTRIDGE, AND THE one we shoot would not even be considered, it is a wildcat plain and simple
 
How do companies that reload used brass make sure that it will work in all rifles?
My first Bolt gun. A Savage Model 10 .308 Win. I jammed it up. Used brass. Some Savage chambers are on the large side. You can feel it in FL die.
Oh! Do you know about putting a little bolt grease on the Bolt lugs??? Well, any kinda grease would work. Just a little. I didn't back then. I guess, the bolt baffle hide the lugs. On a Remington easy to see. Oh, and I know better. I was fixing my Dad's cars at 14 yrs. He could break the stupidest stuff. My Grandpa on my Mom's side was the man to talk to. He worked at Buick and Cadillac in Engineering Dept. He had the best job. Install a piece of junk and run it till it broke or had the miles. Sometimes he would drive home and grab Grandma and they would drive all over the mid 3 states to get the miles. I learned a lot from him in the short time. Found out that I was a good wrench turner. Yep. Proper lubrication is essential to running good machinery. I am always amazed at the number of people that don't know about Bolt Lube. Some are engineers and mechanics. Lots around SE MI.
 
youngtg: The best bet is to get new brass for your barrel and turn the necks on that from the start.

While many of us can in fact swap brass around from barrel to barrel in these BR guns, that's a situation where the same reamer is being used and there's much more control of things...compared to a used gun with an unknown chamber.

New brass is the best investment you can make in a good barrel. It's also important in an unknown barrel to determine how long the chamber is so you know what to trim the case length to. And of course, know for sure the chamber neck diameter is for sure.

These things (and proper die set up) are the biggest things that people get wrong when just starting out with tight necked real-deal competition chambers.

Hope this helps. :) -Al
 
youngtg: The best bet is to get new brass for your barrel and turn the necks on that from the start.

While many of us can in fact swap brass around from barrel to barrel in these BR guns, that's a situation where the same reamer is being used and there's much more control of things...compared to a used gun with an unknown chamber.

New brass is the best investment you can make in a good barrel. It's also important in an unknown barrel to determine how long the chamber is so you know what to trim the case length to. And of course, know for sure the chamber neck diameter is for sure.

These things (and proper die set up) are the biggest things that people get wrong when just starting out with tight necked real-deal competition chambers.

Hope this helps. :) -Al
I really don't know a lot about the rifle....bought it from a family friend and not sure that he knows either. It is a Sako Riihimaki 222 Rem with a tight neck chamber....says "244 NK" on the barrel. To date I have only loaded for factory rifles so I don't know anything about custom chambers. So I FL sized some once used cases and I trimmed them to minimum. I then turned the necks to .009 thickness because I read that a lot of people liked about .002 clearance in the tight neck. I then loaded 30 rounds of Hornady match 53g bullets with mid-range amount of W748. It shot awful....about 1 to 1-1/2 groups...my slingshot does better. I did notice that the bolt had a lot of drag on some of the cases, which may not be good. I ejected some of them (still loaded) and looked at them and couldn't see any marks on the bullet or neck. Something tells me it's the headspace. I have one of those RCBS headspace and bullet seating guage sets and it indicated that the headspace measurement was the same for my fired cases and my unfired cases....so there's something. Also, my case necks went from a loaded diameter of .242 to a fired diameter of .2435, which sounds about right. I'm wondering if it may be worth my money to take it to a gunsmith and get some measurements on the chamber. My name is Garret by the way.
 
Garret, by your measurements, it sounds like you've got the necks turned correctly. Also, it sounds like the head space is correct. Since you're not seeing any marks from the rifling on the bullets, it's hard to tell where the seating depth is. That can be big issue for accuracy. Once you determine that, a standard powder charge work up can be done. Don't give up yet...it may suprise you. :) -Al
 
Garret, by your measurements, it sounds like you've got the necks turned correctly. Also, it sounds like the head space is correct. Since you're not seeing any marks from the rifling on the bullets, it's hard to tell where the seating depth is. That can be big issue for accuracy. Once you determine that, a standard powder charge work up can be done. Don't give up yet...it may suprise you. :) -Al
Al, I think that I will set the cases back .002 and shoot again. Then I will use my CTOL guage and vary that a little and shoot again. Then I will work on speed with the same powder. In the past, I have never gotten big gains by changing powder types, but I have gotten big gains by changing powder amount. I think that it "twangs" the barrel just right and exits at just the right time...
 
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