Fireforming brass....

J

Jackson~in~GA

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I've reloaded for years, but never had a rifle chambered that I needed to actually fireform brass. Well I am considering a 6mm ackley, and was just curious what steps is needed to actually come up with brass? Is it as simple as firing standard 6mm Remington loads in the improved chamber and then sizing it? I have a couple thousand 6mm Rem brass, and two other rifles in the standard version so I should be fine as far as components go. Just not sure on the actual method. Thanks in advance for any help.
 
As long as you seat the bullet into the lands, firing standard loads will form the shoulder nicely.
 
Make sure you use a smith who is acquainted with AI chamberings. Alinwa will probably chime in on this, too. AI chamberings need to be done on the tight side so that the standard caliber brass is very slightly crushed as the bolt is closed. This gives reliable ignition for fireforming and holds the brass in the chamber so that it expands to the AI configuration without stretching the case in the wrong place.
 
AI Chambers

Due to the expansion of the case when fire forming for Ackley chambers, I would recommend new brass not that which has been fired in another gun. Necks and shoulders tend to get hard with use and this could cause some neck and shoulder splitting problems. The new brass is much more flexible and there is less chance of a rupture.
 
fire forming

Jackson-I'm now on my third one(AI) and will offer some advice based on what I learned here, from experience, and gunsmiths. All the preceding advice is darn good. A little more: first, use good brass. New is best; used is ok but I wouldn't use it if were reloaded several times. Then, I use reloading data-my favorite is Sierra's-with these parameters: bullet weight 1 lower than heaviest listed, i.e. a 90g in your case and the load down from max. Use powders in the the "best load" data. Many conversions, .280 AI for example, will shoot their best using the same powder as their "cousins". Fire forming is not a waste of ammo and powder, it is a opportunity!!!!! After each initial round, inspect your brass after firing to make sure all is well. Finally, the process is usually not complete until the brass is fired twice. Don't fret just go ahead and use it as needed, but it will change a tad after it is used in its new form. Finally, I wear safety glasses just in case......Don't know if this helps, but I can assure you I've never had a split base or any other dilemma. V/R Greg
 
I do my own barrel work. This will be my first ackley chambering so any advice is greatly appreciated. I have been told that the chamber needs to be a little on the tight side, and have kept that in mind. I also have a couple hundred new unprimed brass to get started with. Thanks again for the info. ~Jackson
 
I would wipe the cases with a light coat of oil prior to firing. This will allow the brass to flow forward and form the shoulder without stretching the brass near the base.
 
Jackson......

Since you are doing your own chambering, consider setting up the headspace tight on your exixting cases. You may want UP TO .025 crush fit on the Ackley chamber, where you will have to bump back the shoulder on new cases to fit in the AI chamber. A .010 crush fit is just fine, with about .005 minimum I like on my AI's.

When chambers are set up with this CRUSH fit, you should expect groups in the 3's or better on fire forming with loads that are .5-.8g less than formed loads. This CRUSH fit does away with the idea of jamming the lands with the bullet which is a lot of cases is bad JU JU due to the fact that the firing pin fall will seat the bullet deeper in the case resulting in case stretching.

You can work up a fire forming load that is unreal accurate, with the proper bullet seating depth that your gun likes.

When your chamber is set up to have a CRUSH fit on new cases, you can forget ever loosing a case due to split shoulders in fire forming. DO not oil your cases.

You can anneal the case necks, extending the heat sink line a little further down the case on fired cases and save most of them in your ackley chamber, depending on how many of them have been fired many times.
If they split, no big deal. The shot will fly out of the group, ever so slightly, but for a field gun, targets will be dead.

Good luck and you have a very enjoyable project on your hands!
 
Steve Lee said:
I would wipe the cases with a light coat of oil prior to firing. This will allow the brass to flow forward and form the shoulder without stretching the brass near the base.
Click to expand...


PLEASE don't do this! :eek: Brass doesn't "flow" it just squishes in all directions like modeling clay and trying to make the case slide back consistently is an exercise in futility. IF your chamber is so big that you must resort to this madness then it's already screwed up.


Just make sure that you chamber SHORT so that you have to heel the bolt closed with your palm. In fact, I believe you should take this one step further and chamber so short that you must bump every shoulder just a thou or two to make it fit, TIGHT......

GREASE YOUR BOLT LUGS!!!


Chambered short you will gain two real benefits:

-First, your cases will be tightly jammed for proper fireforming, your cases won't banana.

-Second, your necks will remain as long as possible. In fact with a clean sharp shoulder and a solid jam you MAY only lose a thou or two of length. Most Ackleyfied cases shorten dramatically on fireforming which causes huge gapspace.

hth


al
 
I had an awesome 22/250 Ackley imp. until it was stolen! Anyways, to help save the barrel from all that wear from initial fireforming, use a stiff load of Bullseye and top it off with cornmeal or cream of wheat. Then use wax wads that I believe are still available from Graffs and fire away. Adjust the amount of Bullseye you use so that it irons out the case to your liking. If you decide to use this method then make sure between each round you blow out the chamber with compressed air to remove any filler particles. Now you have cases that are almost fully fireformed. Now you can finish the final fireforming with those initial batch of cases while also finding a bullet/powder combination that particular barrel likes. If you need the name of the wax wads then PM me.
 
There have been more old wives tales, urban myths, hype, and plain old BS about fireforming for an Ackley chamber that just about anything else in shooting, including the pros and cons of Moly.

In a correctly chambered rifle, you need only shoot top-end standard loads. Out will come a perfectly formed Ackley case. No need to jam the bullet, oil the case, use COW or toilet paper, none of that foolishness.

In fact, you can shoot nothing but factory or regular re-loads for the life of the barrel and no harm will be done. Ballistics will be only marginally less.

That is the advantage of a true Ackley chamber. P.O. knew what he was doing.

If your chamber is not a true Ackley, you're on your own. A good first step would be to get a new gunsmith. :cool::rolleyes:

And woe be-tide the poor soul who inherits that rifle someday. Just pray that it's not your grandson.

JMHO

Ray
 
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Jackson~in~GA said:
I've reloaded for years, but never had a rifle chambered that I needed to actually fireform brass. Well I am considering a 6mm ackley, and was just curious what steps is needed to actually come up with brass? Is it as simple as firing standard 6mm Remington loads in the improved chamber and then sizing it? I have a couple thousand 6mm Rem brass, and two other rifles in the standard version so I should be fine as far as components go. Just not sure on the actual method. Thanks in advance for any help.
Click to expand...

My son started with 7X57 Norma(I think) and went through a long painstaking process to make 6 AI brass. He took some of my 6MM brass, tried it and it seemed to work just as well. He bought some new Rem 6MM brass and has been very pleased with it. I would get ragged if I told you what kind of groups he was getting while forming the brass, I'm talking very loooww. As a matter of fact he stopped forming and loaded up for a pd hunt and we were popping them at 3-400 yds. with ease. Try loading new Rem 6MM brass and fire away. We could tell very little difference in formed brass vs unformed. The Rem brass performed as well or better than the Norma, with a lot less work. That is one mean round.
 
22/250imp

Jackson

Mine was a tight neck chamber, but that makes no difference. I fireformed all my brass while shooting at pdogs. Accurate just like a stock 22/250. The imp version ran 4064 FPS with a 55 sie and a load of W760. Accurate gun. Never had case problems, click, ect.

Good luck
Dave
 
This has been a very interesting read as I am about to have my 700V rebarrelled and chambered with an ordered 6mm AI reamer ('0' freebore, 1.5 degree taper). So, basically I want the smith to chamber tight. Would it be a good idea to send him some virgin brass I am going to be using? Say, three or four empty cases?

BTW, I'm going with a Kreiger barrel, 1 in 14 twist for the 75 gr. V-Max.

Robert
 
If you are going to play this game, you need to educate yourself about case annealing. Even brand new brass, I anneal after the first fireforming shot. Ever three reloading there after. This will darn sure keep your brass alive.
 
Open Country said:
This has been a very interesting read as I am about to have my 700V rebarrelled and chambered with an ordered 6mm AI reamer ('0' freebore, 1.5 degree taper). So, basically I want the smith to chamber tight. Would it be a good idea to send him some virgin brass I am going to be using? Say, three or four empty cases?

BTW, I'm going with a Kreiger barrel, 1 in 14 twist for the 75 gr. V-Max.

Robert
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JMO but I'd go with at least a 12 twist. A 14 will barely be sufficient for the 75 Vmax...if it is at all:eek:.--Mike Ezell
 
mwezell said:
JMO but I'd go with at least a 12 twist. A 14 will barely be sufficient for the 75 Vmax...if it is at all:eek:.--Mike Ezell
Click to expand...

Then I'd better be thinking about going with a 12 twist. Thanks for your thoughts.

Robert
 
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