Making 356Win from 444 Marlin

[Kestrel4k]

I have ~30 used 444 Marlin brass, going to see about making some 356Win practice ammo.
My research indicated a few different methods that folks have used; without buying a forming die ($$), can I just use my 356Win sizing die & go from there ?
Sounds like it could be possible to just use a good lube and do a careful resize from there.
I figured at that point, I could then see if I need to ream / anneal etc.
Thoughts ?

[BK7saum]

Only apply the thinnest amount of lube to the necks or you will get lube dents/creases.

I usually lube and then wipe off excess leaving only the smallest amount of residual lube.

[cwlongshot]

How many are ya needing?

Yea 100% annealing is required. Your gonna invest time & effort only to find split & useless cases down the road.

I have some brass maybe we can work something out.

[stubshaft]

When I used to form my 307 Winnies I just ran the 444 cases through a 308 sizing die.

[15meter]

That's one I've never done. Based on what has worked for me in the past, I'd start with a 40ish caliber
die to start the necking down. Doesn't need to be down as far as the shoulder will end up but enough to get it in the 358 diameter die. I am guessing you just can't shove a 444 into 358 diameter hole. And going down in increments usually gives better results.

Once you get the neck down to fit in the seater die, do a full length size with the seater die, sans seater stem. Seater die should be a little bigger than the full length size die. Trim to length, then full length size with the regular sizer die.

Test chamber, if it goes in your good, if not, sacrifice a shellholder by grinding .005" off the top and resize and check chambering. Keep grinding until you get consistent chambering.

Time to anneal and check to see if your neck wall is too thick. Necking down that far, you may get into neck turning.

That much movement, annealing is almost guaranteed, with out annealing, you're almost certain to split necks on first firing.

Good luck.

[Kestrel4k]

Thank you all for the good advice;

[Beerd]

Kestrel4k,
have you tried taking 308 Win brass up to .356?
even without the rim, dummy rounds feed/chamber/extract/eject just fine in my Marlin JES rebore.
..

[AnthonyB]

Kestrel4k,
have you tried taking 308 Win brass up to .356?
even without the rim, dummy rounds feed/chamber/extract/eject just fine in my Marlin JES rebore.
..

Plus my Marlin and Winchester. Almost all I use now; the 356 brass is stored away.
Tony

[15meter]

Just because I much prefer "this is what happened when I did this" as opposed to "this should work" I went out to the shed and dug out a couple of 444's. I don't own a 356 Winchester but I do have a 308 die.

First try, I first necked down about the first 5/8" of the case with a 40 S&W die. Then full length size with the 308 die.

Into the die an eighth of an inch, back out, then turn the case slightly and back into the die. Repeated until full length sized. Success, nice looking case.

Try two was straight into the 308 die, same in and out incrementally. Not quite as nice a looking a case but functional.

Based on my extensive testing of two cases going all the way down to 308, I am reasonably sure you can make it to 358.

And I think the intermediate neck down helped.

You will still need to anneal and most likely have to neck turn, but it looks doable.

Good luck.

And I think I just invented a new wildcat.

[rockrat]

I made 356 from 444 by just running the 444 into a 356win die. Trim and anneal

[15meter]

My massive testing on forming down 444 brass to a 444/308.




What a neck. Giraffe neck case.

New wildcat, 444/308 GNC?

[lar45]

I make 309JDJ from 444 with one partial pass in a 308win size die. Annealing is definitely needed afterwards. RP brass works great, starline has a much bigger loss rate.