Should you anneal prior to forming?

[Tazlaw]

I’m trying to form 300blk out from 223/556 brass. I have an annealing set up and was wondering if I should anneal prior to re-forming the brass or wait till after? My minuscule logic says anneal prior to forming. Any advice is most appreciated.
Taz

[djryan13]

It has been said that you get better results if you anneal first. When I first started making 300BO, I had no anneal setup. My brass is fine. YMMV.

If you have an anneal setup, do it if it’s easy enough.

BTW, I first made mine by cutting then sizing/trimming with a 1200. I upgraded to the 1500 trimmer and left the cutting out. Sized/trimmed all in one step.

[BK7saum]

I formed all of mine without annealing. RP 233 and Lake city 556 brass. Did not anneal afterwards either. I have a few reloads on them and no split necks yet. I think I would just anneal afterwards unless you get failures from the forming.

It is not a very drastic movement of brass to form the neck from the body below the shoulder.

[georgerkahn]

Tazlaw -- I'm pretty certain my logic is considerably LESS ;) than yours! That being written, I have very little re-form case experience, with mine being the quite "easy" changes to brass in the Remington Auto group: e.g., .25 Rem; .30-30 Remington; .32 Remington;, etc. -- for mostly Remington model 8s and 14s -- including their varients.
I had thought similarly as you, and have a Giraud annealer as well as other equipment. For the Rem auto brass, I recall the Todd Kindler "circle-torch" head ( http://www.woodchuckden.com/catalog/catalog2016.pdf ) being used -- worked well -- BUT the best results were NOT annealing until AFTER the calibre-size change was done. An observed "justification", a lot of brand spankin' new commercial brass comes with colour marks (Star-Line used to even include a note re this with new brass) from it being annealed as its very last process in its manufacture. Kindly re-read my first sentence ;) -- but, I thought I'd share my wee experience. BEST!
geo

[blackthorn]

My experience has been that annealing prior to reforming results in a high number of ruined/crushed cases. I was forming 22 HP from 30-30 cases, using a 25-35 intermediate die and using pre-annealed cases I had about a 60 to 70 percent loss. When I used un-annealed cases the loss dropped to almost none. I did find that some brands of brass seem to me more amenable to being reformed.

[gwpercle]

If you have the annealing set-up set up ...go ahead and anneal prior to forming .
Annealing softens the brass so it reforms easier with less loss .
In your case you will be expanding the neck . In cases where you reduce the case mouth you may not want to anneal .
Before doing all , test a few ... annealed and unannealed and see what works best .
Lots of variables so no one answer fits every case .
Gary

[dragon813gt]

W/ forming 300 BLK cases it really doesn’t matter. You can produce good cases w/ or w/out annealing. I anneal at the end because I have a machine and it takes little time

For other conversions it matters a lot. What you’re converting to and from matters a lot. W/ multiple step conversions you will find that some steps require annealing while others don’t.

[Mk42gunner]

My opinion only: Try it both ways to see which works for you.

Grumpa (RIP) formed brass as a business, and he recommended annealing last. He formed more brass than I will ever think about doing.

Doing something like making .25-20 from .32-20, in my experience, annealing first results in a collapsed shoulder and a ruined case. A .300 Blackout from .223, probably not.

6.5-06 from .30-06, never did anneal it.
.35 Whelen from .30-06, expanding necks is easier with soft brass.

Good luck and expect to lose some cases to learning,

Robert