The necks need reamed or turned. I have a 44AMP case forming die so initially I'd just run the cut off cases into that and use that reamer tool, but eventually just got a .427" reamer use on the final trim. Sizing is an issue as well. Not all 444 dies will size a 1.8" case down far enough to get any neck tension. You can run them in a 444 sizer, then run the top .5"-.75" into a 44 mag die. Eventually I just bought a Lee 444 die set and trimmed them so they would work with the shorter cases. It's not hard to make a straightwall sizer die though. Bore the hole to whatever the neck dia needs to be, then add in the taper ending behind where you'll have the deepest seated bullet.
Top is a 444 Marlin with a 240 Rem sp. Then 444x1.8 (started out as the shorter Hornady brass) with a 265ftx. 44x1.8 AR15 load, AR308 and Mauser loads are a bit faster as you can seat the bullet out further which makes room for more powder. Next three are 44x1.6 (like a rimless 445SM with the same length and case capacity) 240speer, 225FTX, 265 Hornady. 44mag with 240 xtp that I shoot out of my 44S&W's and Marlin. 44 Havoc which I'll do a writeup on eventually.
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