Stan, I wish it was changeable, but they are single use stamps. They're under ten bucks at Rubberstamps.com

Ordered 3 roll crimpers today from The Reloaders Network
10b; 12b & 16b
Thanks for the heads up!
Jim

Thanks, Edgar. I'll look at that site.

I got my tools from Reloader's Network. Just to test a few things out, I made 2 quick 16 gauge shells with a hand drill and their shell vice. It was easy and I like the results...

I just ordered a $49.99 quad pin 10 gauge roll crimper off reloaders network from the “loads of bacon” YouTuber. There really only two other currently manufactured roll crimper I could find. A one pin from BPI and a 2 pin from precision reloading. Both for $28, plus shipping, plus tax. So for another $10, or less, I ordered the quad pin roller with zero tax charged and free shipping. Cant wait to try it out.

I cut these hills down and glued the shot cards in place. The cuts aren’t perfectly even. Is there enough hull left to roll crimp my shells below? Do I need to cut them perfectly even to get a good roll crimp? I hot glued the shot cards in place so I would assume it would make a mess. I will probably just shoot these up and start with fresh hulls to roll crimp. Just wondering how much hull I need to leave above the shot card for a proper roll crimp. Cant wait! I’m guessing with using this roll crimper I can load shells that will reliably feed and keep the shot inside my hull while cycling through a semi auto?

https://i.imgur.com/BVeWIhi.jpg

You will find the Ross roll crimper to be an excellent tool. I've tried all the others, and have been rolling my own for years.
You will find the amount of hull above the overshot card, necessary for a good crimp varies a little, depending if the hulls are cut down or NEW and Skived. The difference is the thickness of the wall to be rolled. The rollover only needs to make a 180 degree turn, and any more than that is unnecessary, and may result in slight increase in pressure.
I leave about 3/16" of excess hull on 12ga. New Cheddite hulls, cutdown Federal hulls, and some New Paper Alcans I bought here.
My 28gauge hulls, with 3/4oz. of 7.5 or 8 shot, cut to 2 1/2", leave more with SG28-II wads than Fiocchi RO28 wads. I stick with hull lengths that match the chamber for best gas seal. I don't want to trim hulls to accommodate certain wads, so until I find a filler, I'd either have to use an extra couple overshot cards, or end up with an unnecessarily deep rollover.
I'm making it my rule of thumb is to find the correct wad for the shot/powder charge, and not vary the case length because of a compromise in components. Not easily done with the shortages we see today.
To your question about the cleanliness of the cut; yes, it matters. If you do a search, you'll find the hull trimmer jig I made, which yields a perfect edge.

Thanks for the tips.

My efforts with roll crimping plastic hulls resulted in very nice finished shells (after a bit of effort and experimenting) but after firing the mouth of the cases was a mess. It retained some inward "roll" and was pretty ugly, basically non-reloadable. Is this the norm or am I doing something very wrong?

Dug these out of the trash.

Your fired hulls appear they were skived. The plastic does retain some memory, and will still exhibit a slight inward roll, which needs to be conditioned before de/repriming and sizing. Several suppliers sell a tapered aluminum tool which does a good job at this. plunging the tool (in the drill press) and holding it for a few seconds, to generate heat, brings the hull back to a reloadable condition.
Paper hulls retain no memory so this isn't an issue.
The only plastic hulls I reload are trimmed to 2 1/2", so 2 3/4" once fired hulls loose the skived portion, and all the new plastic I load are either purchased, unskived, to length, or trimmed to 2 1/2" from new 2 3/4" purchased hulls.