That's an interesting challenge you've taken on with those Desert Eagles! I've always been fascinated by them, especially the .44 Magnums, but yeah, I've heard about the reputation for being a bit finicky, especially with hotter loads.

It sounds like you've made some good progress on the feeding issues by modifying the magazines. That's a smart move! Now, this business with the hot loads ejecting straight into your face...not exactly ideal, to say the least! I can understand your frustration, especially since you don't want to sacrifice the power of those .44 Magnums.

Your theory about the slide velocity and case wall rotation makes sense to me. Maybe there's something you could do with the recoil spring? A stronger spring might slow the slide down a touch and keep those casings ejecting where they belong. Just a thought!

I'm curious about the L5 piston you picked up. I'm not a Desert Eagle expert by any means, but it sounds like you might be on the right track there. Even if it is a little too short, maybe it could be a starting point for some modifications? Definitely worth a test like you said.

Hey, and if all else fails, there's no shame in running slightly milder loads. It's better than getting smacked in the face with hot brass every time you pull the trigger, right? But knowing you, you'll probably keep tinkering until you find a solution that works with those full-power loads. Good luck with it!