Fireforming

13 June 2004, 18:30

3584ELK

Fireforming

Recently I was given a Siamese Mauser chambered to a .45 caliber cartridge. I poured a chamber cast and it sure looks like a .450 Alaskan, .450 Fuller, or .450/348 Win Imp.

I annealed some .348 cases, loaded them with 20 grains of AA5 and 38 grains of Malt-O-Meal, topped with a wax plug. I fireformed a few, but they didnt quite have the full shape. I then ran them back through a 2nd time, and they formed nicely. I tried shooting into a large plastic tub (with eye and hearing protection) and was amazed to see the wax plug blow a hole through the bottom!!!

Question- Does the 2nd round of fireforming have a detrimental effect on the case life?

At any rate, it looks like a fun rifle, and being a big- bore fan, I am excited about the results. I started a few loads with 53.0 gr. H4895, and a 405 gr. FP. Any suggestions?

Thanks guys!

14 June 2004, 04:38

snowman

3584 the fact the first fireforming is not properly forming the cases tells you the pressure is quite low. I believe a faster powder such as Bullseye might be better suited .Perhaps someone out there that has fireformed this particular cartridge could recommend how many grains of Bullseye. Your best case life will be obtained if you headspace off the shoulder of the cases rather than the rim.

14 June 2004, 16:34

Ray Gunter

I remember a formula where you used a charge that was a 10% of a full case of powder. Where if you were using Unique you would fill the case full and dump it in the scale an weigh it then calculate 10%.

Dont use a bullet just top with cornmeal or cream of wheat.

15 June 2004, 02:26

boha

This fireforming thing is interesting; Iï¿½ve formed AI cases from factory loads, but now I have an old rifle with excessive headspace, that need special cases - expanding with a larger exp, and then sizing to the proper headspace and blowing it out... About this cornmeal stuff or cream of wheat, do you just pour it on top of the powder and keep the cases and rifle upright, or what?

This thread came as an answer to a prayer

Boha

15 June 2004, 05:45

dan belisle

Yes that works fine. Don't shoot them indoors, tho', it's messy and noisy, as well the powder charge WILL blow through a plastic bowl. - dan

16 June 2004, 07:09

boha

Thanks! Iï¿½m off fireforming..

Boha

16 June 2004, 08:19

MuskegMan

One tip I have for fireforming (and I've done .30 Herrett's, .30 Gibbs and 375 Taylor) is to use a small amount of lube (imperial, WD-40, etc.) on the shoulder and neck area. This aids in forming sharper shoulder and neck angles on the first forming. I always go to near-full power loads after that. I wouldn't recommend this method if you are using the "bullet-jammed-into-the-lands" method of controlling headspace as some like to do, though.

18 June 2004, 16:59

3584ELK

UPDATE!

I shot the loads I made up, and they are very mild. I can tell this is going to be a great project. Lots of boom, a fairly slow recoil impulse, and a BIG hole in the target!

Moving up with the charge weights now...

03 January 2006, 14:15

tera

quote:
Originally posted by 3584ELK:
Recently I was given a Siamese Mauser chambered to a .45 caliber cartridge. I poured a chamber cast and it sure looks like a .450 Alaskan, .450 Fuller, or .450/348 Win Imp. I annealed some .348 cases, loaded them with 20 grains of AA5 and 38 grains of Malt-O-Meal, topped with a wax plug. I fireformed a few, but they didnt quite have the full shape. I then ran them back through a 2nd time, and they formed nicely. I tried shooting into a large plastic tub (with eye and hearing protection) and was amazed to see the wax plug blow a hole through the bottom!!! Question- Does the 2nd round of fireforming have a detrimental effect on the case life? At any rate, it looks like a fun rifle, and being a big- bore fan, I am excited about the results. I started a few loads with 53.0 gr. H4895, and a 405 gr. FP. Any suggestions? Thanks guys!

TERA

Could you give me information on the box of 450 Fuller Of which box one can form it thank you his length
(information which I then to do it)
is has soon

03 January 2006, 15:57

jeffeosso

you'll have to experiment with the proper charge of powder ( i like bullseye) ...

then fill to the neck with corn meal/cream of wheat

then top with a packing peanut, or wax, or (great idea) florist form...

at a safe range
load, tilt Up, thump/tap/bump rifle
leave aiming up (experiment with this.. up makes better cases than level) fireform

run though your dies, assuming the shoulder is close enough

pop off a good load (email me for a known good 450 alaskan load) and you'll have perfect brass

jeffe

03 January 2006, 23:31

Con

I separate the inert filler from the powder with a small wad of toilet paper. Another small piece of toilet paper on-top of the inert filler and push the case neck into a slice of potato or pumpkin. I experiment to get the right powder charge to fireform on the first go.
Cheers...
Con

04 January 2006, 05:47

338guy

I have a 450 Alaskan on a Model 71 Winchester. Use large pistol primers. I use 18 grains of Bullseye, 1/4 of a piece of toilet tissue, fill case almost full with corn meal and cap with a piece of canning wax.

Cases come out perfectly formed and I have never lost a case if I use new brass. I would only use new cases as I tried fired cases and suffered split shoulders. After this fireform load trim to length and load with a normal load.