All of mine are once-fired only. I have over 1,000 in 16 ga., over 1,000 in 20 ga., over 500 in 28 ga., and at least as many 12's.... all once-fired.






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After dropping the shot you could try adding a standard overshot card before you crimp. This will flatten the final crimp to the shell perfect. For 12 gauge, use 16. For 10, use a 12, etc....

I was getting dished crimps like the picture Pete posted when I needed to switch to 700X which is a more dense powder than Clays since I ran out. The overshot card made a nice tight flat crimp and you get confetti for special effects when you fire off the gun....

When I was a kid (re. paper shells) I found that bee's wax candles worked better than paraffin for sealing shells. It seemed that the bee's wax would stick better and wouldn't flake off as the shells got bounced around in my hunting coat. Now with a properly adjusted crimp die and plastic wads the problem doesn't come up very often.
C.G.B.

I've been using candle wax for decades. When I was shooting registered skeet the 410's got the most use from a candle.
Dean I'm loading all 2 1/2 inch RST as well and once in a while you pick up a shell that's a different crimp. as they age (get used) the crimp memory degrades and the candle comes out. This reminds me I need a new candle:)

COB, those .410s can be a bugger, especially when one loads Rem, Win and Fiocchi hulls. I use a lot of overshot cards. I'll use them for most of my shells, .410, 28, 20, 16 and 10. Don't need them for 90% of my 12g 2 1/2" shells. For some reason my 12g crimps are usually right on the money. I also use them for my 12g Black Powder paper shells. Really finishes off that crimp.

I always used the Win AA hull in the 2 1/2 inch 410. Never had a problem with them but back in the day I would load them until the crimp was shot off:eek:
I could use them a dozen or more times until the wax came out to hold the shot in:rotf:

I have some vintage smallbore candle wax that I could let go real cheap.:eek:

ive waxed for decades and found toilet paper to be as good if not better. issue: wax dries. if you shoot shells with wax in a semi auto, the feeding stress can cause the wax to pop out.
if you shoot a lot, the wax melts inside the bore.
if you reload, the old wax on the crimp gets jammed up in the deprimer and resizer die.
though ive never had a safety issue with wax, those that do it should be aware of these additional things. I hope it helps.

I might add that if you use wax, while its still clouding over and soft....smash it down with your thumb, to make it form into the top lead and lock into the crimps from the inside. itll have less chance of falling out.

Ok, now I am torn between wax and toilet paper.