Question on 455 Mark 11 cartridge

I would like to know the rim thickness of the 455 Mk II cartridge


seems to be some variation

Looks like .029-.036 if this is accurate...

Thank you for the information. I measured a few in my collection and they were .031 to .035
while the .455 Colt was .043 on the rim thickness.

I think the .455 Colt is on the short side as regards case length, yes? Or is it the other way...

I do know that when I got some Fiocchi .455, the cases were so short versus my stash of CIL/ Dominion cases, that I had to shorten my seating/crimping die. Don't remember any more how much, but it was significant- maybe 0.080-0.100"?! (As they were originally .45 Colt dies, they're now REALLY short- lock ring about has no theads to engage.)

The Dominion .455 Colt actually was closer to the old .476 Enfield and to the really early Blackpowder rounds.

NICE, because you can trim them halfway to Sunday and still re-use them.

You can make .455 brass from .45 Colt easily enough and it will work, even though the rim isn't as wide as it should be. I have seen .455 made up (in desperation) from .303, although .30-40 might be a better bet. Good reason to buy a Krag with a bad chamber!

Just thinking (I do that sometimes) about .455.

A relatively easy way to make up brass that is very close to the old .455 Colt is just to thin the rims on .45 Auto Rim. I know that this one is supposed to be obsolete, but there have been batches turned out quite recently and it is listed by Remington and Starline. Nice, wide rim for easy extraction, too!