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ahall
02-15-2019, 12:22 AM
Has anyone tried 32 ga shotgun brass as a parent case to reform into 12.7 x 44
If you have done it, how well did it work?

Sure, I could buy cases already formed, but what fun is that?

I see that most use one of three options - 50/70, 50 Alaskan or 348 Winchester, and I could make any work.

I know the Magtech brass is thinner in the head then the rifle brass, however that is closer to the period shells the gun was designed for, and gives an increased case volume so its worth thinking about.

My chamber casting shows no step for the end of the case or free bore for the bullet. The chamber is simply a taper entering the rifling so case wall thickness may become an issue. The OD of the groves start out some where around 0.517 and the chamber OD is about 0.530 at the 44 mm line, so .006 or so on the case wall if we want the bullet to fit the bore and don't want a healed bullet. I still have to slug the bore and verify the measurements, but the casting is a starting point.

Either way, the lathe will take care of the mold, but its easier to lube an bullet without a heal in the sizing press.

Has anyone compared the wall thickness of the 32 ga, 50/70, 50 Alaskan and 348 Winchester after trimming to length?
That may be a deciding factor for me.

The rim thickness is also a concern. Head space is on the rim and may be excessive with 32 gauge. I am going to turn a dummy head and figure out the maximum rim thickness that the block will close on before selecting parent brass. CIP has the nominal thickness and tolerances for 32 ga, 50/70 and 348, but not 50 Alaskan. Nothing on it from SAAMI either.

OK I know, I am way overthinking this, but I would like to verify the rim thickness on the 50 Alaskan before investing in the brass.
There seems to be $100 minimum on any of the cases.

Finally - 50/70 dies seem to be a popular idea for reforming the cases.
Does anyone have experience with this to share?

Thanks.

elk hunter
02-15-2019, 10:33 AM
I made mine out of 348 and 8mm Lebel cases, both work well in my Huskvarna. I don't size the cases after firing forming them, I hand seat the bullets in the case mouth so I don't need dies. I've used the brass 24 gauge shotshells for 577 Snider and can't say I really like them as they split if not carefully annealed, I suspect the same would be true of the 32 gauge cases.

ahall
02-15-2019, 01:52 PM
Used the 24 ga for 577 snider and 577/450
Understand the issue of case splits and the need to anneal.


I see that 8 mm Lebel is currently reasonably priced at Midway, but I am unfamiliar with Prvi Partizan Brass
How does it fall out relative to Starline and Beatrum?

With 8mm did you fire form or work through a set of expansion plugs
Love to learn from your experience rather than hard knocks.

17nut
02-15-2019, 03:24 PM
I have made 12,7x44R from 32 gauge Magtech and it works a treat!
I size initially in a 50-70 die and then fireform to rifle.

236072

ahall
02-15-2019, 08:43 PM
17 nut

Do you anneal the brass to avoid splitting or has that not been an issue?
Have you tried other cases and do you have an have an opinion on 32 ga relative to the other available options?

17nut
02-16-2019, 06:20 AM
I have tried 12,7x44R Bertram, Winchester 348 Win and 32 gauge.
And to be honest i see no real difference.
The only "issue" with 348 is the slightly smaller rim and the extractor might slip past once in a while.

32 Gauge is by far the cheapest one here in Europe at slightly over €1 a piece.
348 is at least twice that and Bertram/Hornebeer original 12,7 is more like €4-5 a piece.

elk hunter
02-16-2019, 12:42 PM
Used the 24 ga for 577 snider and 577/450
Understand the issue of case splits and the need to anneal.


I see that 8 mm Lebel is currently reasonably priced at Midway, but I am unfamiliar with Prvi Partizan Brass
How does it fall out relative to Starline and Beatrum?

With 8mm did you fire form or work through a set of expansion plugs
Love to learn from your experience rather than hard knocks.

I did it the simple way by first annealing the original case then loading a lite charge of Bullseye, a small piece of tissue, corn meal to fill the case and capped with a wax wad. I then fire formed them and trimmed them to length. The cases did show impressions of the rifling but didn't split. My load is 28 grains of H4198 and a soft cast bullet from 350 to 450 grains sized or patched, depending on the bullet, to .508 diameter. It shoots as good as I can hold it. I'm thinking I'd like to try it on a deer or an elk.

I'm sure 50-70 cases would work but I save them to make 56-50 cases for my Spencer as it doesn't like the new small rimmed 56-50 brass made for the reproduction guns.

17nut
02-16-2019, 01:04 PM
The cases did show impressions of the rifling but didn't split.

348 Win do that to.

236109
236110

soflarick
04-27-2020, 12:50 PM
I haven't had my 12.7 Swede for long, and just began acquiring components for reloading. I just received some 32 gauge brass, and I'm working on one piece of brass before going further. Trimmed it to 43.90mm, ran it through a 50-70 sizing die all the way down to ensure as much of the case is sized. Inserted into the breach, and the last mm or two are still too large in diameter to fit the chamber. Chamber and barrel are clean, btw. I tapped in the brass with a brass rod, and removed with a brass rod from the muzzle side. That last bit of case that won't go in has striations that indicate the diameter is too great. Has anyone experienced the same? Rim diameter is .627", and seems to fit the cutout of the chamber quite well. I'm thinking perhaps I should try 50 Alaskan brass instead.