Here's a repeat of one of my prior messages on the subject of cappers:
I've got 5 cappers of various makes & designs and even the Ted Cash capper wasn't that great til I modified it. Now 4 of 5 will fit the Remingtons. Here's what I did:
On the cheapo cappers from McGees that go for about $4 (single spring) I ground off the lip of the spring to where it just held the cap flush with the spring and no overhang beyond the cap. I also ground back the corner of thebrass housing on the opposite side to shorten it and put a taper in it so that the brass only just supported the cap but didn't stick out beyond it. For the Ted Cash capper, I just ground off the lips of the springs as before so the capper could be inserted deeper and it works fine. The TC capper is a weaker design and the brass backer bends easily so I actually prefer the generic cappers that have a 90 degree brass support of the cap and will not bend during a fit of anxiety while capping on the clock. The cheap cappers hold the cap like on a piece of angle iron where the TC is like on flat band iron. I've even considered epoxing a small nail or something to strengthen the TC's tip but figured I'll just take it easy with it. You need a grinder or a stone and some extra time to fix the cappers for Remingtons.
For the Colts just about any in-line capper will do. But the "Remington modification" makes them faster.
As for the teardrop cappers, I keep dropping caps out of them and losing caps in the gravel at the range. When they work, they work well for Colts only.
I keep an in-line capper and a nipple pick on a cord through my vest button hole for on the clock "reloads".