fireforming to improved chamber with once fired

[ohnomrbillk]

I'm working on a 338 Lapua project, and have a few questions. I am not new to reloading or to wildcats, but I have never started with brass once fired in a standard chamber. Potential noob warning.

I'm planing on doing one of the improved versions. I have not decided on which one. Regardless, it will decrease body taper, and increase the shoulder angle. It will be set up like an Ackley for fireforming purposes.

I acquired some very nice once fired brass from a good friend. Some is Lapua headstamped, the rest is Nammo Talley. I intend to sort lots by headstamps at a minimum.

Since this will be a more dramatic fireforming, would it be worthwhile to anneal now?

Would you full length size before this fireform?

If you did full length size, would you do it with regular 338 Lapua dies, or with the improved dies.

I tried using the Google search engine for Hide, but no luck.

Help appreciated.

 

[armorpl8chikn]

Re: fireforming to improved chamber with once fired

FL smallbase size now. Then anneal.

 

[MitchAlsup]

Re: fireforming to improved chamber with once fired

Since this will be a more dramatic fireforming, would it be worthwhile to anneal now? Probably, but not mandatory. Also don't expect superlative accuracy from the fire forming firing.

Would you full length size before this fireform? Absolutely.

If you did full length size, would you do it with regular 338 Lapua dies, or with the improved dies. Factory barrel--regular, tight chamber reamer--improved.

 

[BuzzBoss915]

Re: fireforming to improved chamber with once fired

As has been said; my vote is full length resize, fireform and then anneal, although I don't see any rush.

You might also consider fireforming without a bullet. I do it to save on rather expensive bullets, not to mention barrel wear/round count. If you do, stay away from fillers such as cream of wheat or corn meal. BB

 

[leadbullet]

Re: fireforming to improved chamber with once fired

fireforming loads can be very accurate, I have shot match with a 243 Ai FF load and did realy well (2nd pace) I have seen other F class shooters fireforming 284 brass at matches and winning them also.
Anything can happen, full length size and fireform, then anneal.
hope this helps.

 

[jcfd2201]

Re: fireforming to improved chamber with once fired

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: attherange</div><div class="ubbcode-body">fireforming loads can be very accurate, I have shot match with a 243 Ai FF load and did realy well (2nd pace) I have seen other F class shooters fireforming 284 brass at matches and winning them also.
Anything can happen, full length size and fireform, then anneal.
hope this helps. </div></div>

I will 2nd this. I just recieved my 260AI from my smith a couple of weeks ago and have loaded up factory 260 brass and had great accuracy results while fireforming. I have not spent an abundance of time working up a perfect load as I will do that for my AI brass and results are still impressive.

 

[MarinePMI]

Re: fireforming to improved chamber with once fired

I think some may have the ordering process a little mixed up.

FL size, anneal, then fire form.

FL size to bring it back to SAAMI specs.

Anneal to remove work hardening and allow the case to more easily fireform to the chamber.

Fire form to your chamber.

Since this is (at least) once fired brass, annealing before fire forming would be good insurance, especially if this is a drastic change. Radical or drastic changes tend to split necks if the case is work hardened too much.

It doesn't matter if its a .50 Ubersnot Match or a tiny .17 Ackley Hornet, anneal before fireforming for cases that have a radical change in taper and shoulder.

JMTCW...

 

[BuzzBoss915]

Re: fireforming to improved chamber with once fired

I guess I have been doing it wrong? I have never annealed before fireforming and never experienced a split neck while fireforming. I'm not recommending that somebody do it my way; I am just describing what I have done before; many times for a half a dozen different calibers. And, based on that experience, I do not believe annealing would hurt anything, but I don't think it is necessary, either. So, do it if your heart is set on it, or don't do it and don't worry that you might be screwing up royally. And, if it is a "radical" alteration and requires two fireforming(s) for a sharp shoulder, BFD. BB

 

[ohnomrbillk]

Re: fireforming to improved chamber with once fired

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: MarinePMI</div><div class="ubbcode-body">I think some may have the ordering process a little mixed up.

FL size, anneal, then fire form.

FL size to bring it back to SAAMI specs.

Anneal to remove work hardening and allow the case to more easily fireform to the chamber.

Fire form to your chamber.

Since this is (at least) once fired brass, annealing before fire forming would be good insurance, especially if this is a drastic change. Radical or drastic changes tend to split necks if the case is work hardened too much.
JMTCW... </div></div>

This is what I was envisioning as the best option.

As others mentioned, I've had match grade results with fire forming loads, but I've always used virgin brass.

Thanks for everyone's input