Guy I hunt with has inherited a .444 Marlin from his soon to be dead former son inlaw. The son inlaw was not smart enough to get more then a box of ammunition and finding .444 Marlin brass is a problem. Hunting buddy has sourced some .444 Marlin but I have read that 30-06 brass can be successfully sized to work. The problem is that the ones that have posted they did it never bothered to post the steps they had to use.

I have a Lee Bell Die so I can bell the case mouths and I have one case necked up to .323. I have a lathe and I have the final neck forming pilot made.

Problem is there just are not that many rifle calibers between .323 and .429. I am using RCBS rifle decapping rods to mount the neck sizing pilots to because I have a supply of them that I bent the tips on so I can cut them in my lathe to work. I also have this thread pitch in my tap and die set so I can thread the pilots.

If there were more calibers in the range I am working with I would use new decapping rod for each step. Bimart has a selection of sizing collars so I may get lucky tomorrow but I suspect that I will have to cut the step sizers on my lathe. and If I have to do that then I will just thread them to fit the OD of the decapping rods.

I have three expanders made but the taper is now fighting me so it looks like I will have to deprime a few more cases and anneal them using the pan of water technique.

30-06 brass does have a rim just not much of one. Looking at the case dimensions for .444 Marlin I can see that it headspaces on the rim and the taper as it is not a straight wall cartridge,

About a buck a piece is the source I found too. If I had not found two articles in two different online groups I would not even be attempting this.


My Question is has anyone in the group already sized 30-06 up top .444 Marlin and how did you do it?

The .444 Marlin uses a rim for headspace. The 30/06 is a rimless case. IF the rifle's extractor works with 30/06 brass, you'll need to control case length carefully to manage headspace. But it may not extract at all, depending on the rifle.

You can easily step up from 30-35 cal in one pass, then to .410" in the next, and .429 after that. No need to go through every caliber available. You will need to learn annealing though, if you aren't already set up for it.

https://palmettostatearmory.com/starlin ... mareu.html
A little on the pricey side but it is in stock.

I got it figured out. It is a combination of cutting the case to a length and then using a forming plug that I made to open up what is left of the taper. The steps involve using 30-06 .444 Marlin dies and .44 Magnum dies. I wind up with a case that is 2.045 inches long once trimmed and I am able to crimp them to .444 Marlin OAL.

reported to the Mods so they can move this to the general firearms discussion. Glad you got it figured out and this might be useful for someone in the future.
That way the post won't drop off like the classifieds do.

Good eye, Paris. Thank you.

Moved from classifieds to discussion.