That was my exact initial concern after taking one out of the package. The cup will literally just fall right off some of them.
I took each of them off and bent the "petals" inward a bit and reseated the bullets and they stay in place much better but I will certainly see what sort of bore fit they have and thanks for the heads up. It would kind of suck to have the ol' cartoon bullet roll out the barrel when you really need it huh?

I also thought about the dab of superglue as well but wondered about the gas check staying attached a little too long or maybe not dropping off.......probably would I guess but no real way to know without shooting some sort of medium like gel or sand or something.
I think if the bullet stays seated OK I might be in the chips but I'll keep a close eye on them. Maybe even TRY to make one come out by turning the gun over and trying to shake it loose (Re seating of course before firing to make sure it's not 1/2 way down or anywhere in between)
Accuracy wise they realistically only have to be good to about 75 yards tops for the majority of my hunting with the flintlock here in PA. Probably the longest I've taken is somewhere around 60.
I hope someone has some experience on game........curiousto hearhow they did.