Case forming 45/75 from 348 brass - help

[10gaOkie]

I am needing a step by step case forming of the 348 to 45/75 working from new 348 brass. Then fire forming with black powder, shooting a 340gr cast bullet.
I just dug up all my brass in various stages of forming but cant remember the equip I used. I do have a 38/55 expander die that I used along with the Lee die set for 45/75. Any help would be welcome.
Thanks,
Chris

[country gent]

Could it be as simple as anneal, load a charge and wad then fire form and trim to length. If going the forming route I would try 38 caliber ( .375/.380 dia) then 40 caliber (.410 dia) and last a formed expander 45 caliber. Ideally this would be slightly big around .003-.004 also I would make it on the long side. With this expander when full length sized the case will be pushed down to the final form very close in the full length sizer. Ammo should shoot good with the fire form loads. Anneal at the start then when finished again. Brass will thin and shorten some from the expanding up.

[10gaOkie]

I didnt think it would be necessary to anneal the brass at the start since I am using brand new 348 brass. There are about 50 rounds that were almost complete. They have the top of the shoulder 1.400 from the base with a .775 long neck. Over all length is 2.185 with a .452 mouth. I just wasnt sure how I got to that point. My guess was using a 38/55 expander 1st, then a .444 expander 2nd, then the 45/75 sizer. I cant figure out why the mouth is .452. I didnt have any split necks so whatever I did must have worked.
Now I am wondering if I am going to have to buy a complete die set to get the 40ish expander die.
Chris

[10gaOkie]

At this point, this is my thinking. Using the 38/55 expander 1st, then use the 40/65 expander 2nd, then use the 43 Spanish 3rd and finally the 45/75 expander and sizing die, finally anneal neck and shoulder. I would have to buy the 40/65 and 43 Spanish die sets, dont have those two. Then fire form with FFg with my 340gr cast bullet sized to .457. Not sure what the powder charge would need to be?
Chris

[Steelshooter]

Go to https://www.buffaloarms.com/. They should have everything you need.

[10gaOkie]

Steelshooter, For some reason my computer will allow me to get on the Buffalo Arms website but I do have their phone number. What parts are listed that you had in mind? As it stands, I can buy those two complete die sets from Natchez for $54.
Chris

[Steelshooter]

Go reloading supplies, then go to expander balls. They are 20.00 apiece, for lyman and rcbs dies.
Sorry reread posts and I see you have lee dies.

[Duckiller]

Why? Starline sells brand new 45/70 brass. 348 brass is hard to come by. Posted by a 348 owner.

[blikseme300]

Not forming 45-75 but I use 300WM once fired brass and fire form these to 458WM without using intermediate expanders. I do anneal before and after or necks will split.

[10gaOkie]

I bought all of a guy's supply of new 348 brass at a gunshow some 15 years ago. At least 900 rounds. Why on earth would I want to change to another parent case. /Chris

[ascast]

have you tried fire forming? Did I miss that part? 10-15 grains Unique,fill to neck with cream of wheat, 1 sheet toilet paper poked in to hold it there point skyward and shoot. Repeat with bullet inplace of wheat/tp.
Final neck trim == done

[10gaOkie]

I have not tried fire forming. Do I need to trim the 348 case to 45/75 length before fire form? I have all kinds of powders be no Unique. /chris

[country gent]

I would experiment here trim 1 case length to 45-75 length and fire form measure again and see how much it shortens from expansion. Add this amount to the next one and try again. Measure it and if it right or very close ( it should be very close to case length) add .010 and repeat again. Ideally you want the newly fire formed brass to be slightly long ( .005-.010 ) so after fire forming they can be trimmed square and dead on for length.

[10gaOkie]

The main reason I have never fire formed from a unsized 348 case is it will not go into the 45/75 chamber. 45/75 has a much lower shoulder than the 348.

[salpal48]

There has been a lot Of Discussion about 45/75 from 348. I have used starline 50/110 or There 50 Alaskan better suitable
anneal prior and Run slowly Into size die with Out Decap rod
Seems to work very well

[10gaOkie]

Like I said before, I invested in a good supply of new 348 brass to feed my M71 and this 45/75 project. I am not about the change this late in the game. /Chris

[ulav8r]

Tried to reply a couple of days ago, don't know where it went. My take is sell the 348 brass to someone who wants brass headstamp to match their gun. You can probably sell it for more than you would pay for Starline brass with the correct headstamp for your gun.

P.S. I misread post about Starline brass. They do not have 45-75 as I mistakenly thought. Still, just because you have more 348 than you want is not a good reason to not sell it to someone one who needs to feed a 348. Or offer to trade 200 348's for 3-400 Starline brass.

[lucifers]

Like I said before, I invested in a good supply of new 348 brass to feed my M71 and this 45/75 project. I am not about the change this late in the game. /Chris

Because that 348 brass is worth a lot of MONEY. 900 cases are 3 lifetimes worth. Keep 200 for your 71 and sell the rest.

https://ammoseek.com/ammo/45-75

Starline does not show 45-75 brass on their site.

[10gaOkie]

Thanks for the advise about selling my brass. I am not worried about that. I am looking for some shortcutts or advise in forming 45/75 from 348 brass. /Chris

[Hiwall55]

Run the 348 into a 45-75 die till it chambers then 10 grains of bullseye and fill with COW then fire straight up ,no toilet paper can make necks split, then trim for length on the next one leaving a little long. This works 100% when making 40-_
60Maynard from 30-40 Krag.