My all time favorite and what I recommend if asked are Remington #10's. Do so as of all of the big three (Rem, CCI, RWS) the Rem 10's fit the nipples/cones the best and for the most part stay on the nipple after firing and are easily removed. Its been so long since I've had anything fall into the guns interior I can't recall. Possibly back in and around early 2005 when I bought a 2nd model Dragoon and used some old Remington #11's that were handy that I used on my TC Hawken. Just got the Dragoon, cleaned it up, and headed out back to my farm range as I was in a froth to shoot it. Had a cap fall into the guts on the 2nd shot. Went back in the house and got some Rem 10's and had 'a more harmonious outcome'.
Anyway, the Rem 10's have the longest skirt of the 'big three' that will fit over the nipple and the longest internal depth that will fit inside. That's why they are popular for fitting on the nipples and staying put so to speak after firing and not falling apart and into the guts of a cap revolver. CCI 11's are the next best IMO and from alot of other positive reports I've read over the years. CCI 11's are a bit smaller in their dimensions than Rem 10's, but are the closest to them of all of the others. I've used RWS off and on several times but not enough to say ya or nay. I did buy 1000 of em on the cheap at a gun show not long ago and haven't given them a real side by side comparison to the others I use alot. One of these days I hope to do a comparison with my stable of cap guns using the 'big three' caps on the four brands of nipples I have available on by revolvers. CCI 11's are often quoted as being the cap that Treso's, Slix-Shot, and Track of the Wolf nipples were developed around. Tracks nipple is a close copy of a Tresso but made from stainless steel. I and others have found Rem 10's even work better in our experience than the CCI 11's and fit well on the three after market nipples. The Rem 10's I've found work well with factory nipples also, in fact on some of my cap revolvers they still have what came on them.
I've posted this info before, but if any one wants to read a well written thread on percussion caps, go to the CAS Forum. Click on 'The Darksiders Den', then at the top of the Den, click on 'The Dark Arts'. Around 2/3 of the way down is a thread started by a guy called MAKO titled "Cap Gun Primer: Correct Cone Length". It is a three page thread written by MAKO using CAD drawings of cap and ball revolver cylinders/nipples, hammer relationships, etc that is very interesting and informative. Read the whole thread, it was written before Slix-Shot nipples were produced and Treso's were all the rage. The thread really gives top info on the relationship between cap and nipple fit, how well a striking hammer hits the cap, and other not well known information. On page 2 post #20 is a chart showing all of 'the big three's' percussion cap dimensions. I'd just put a link here, but beyond my pay grade how to go about that. MAKO in his day job was an engineer of some sort who worked with CAD machines and loved black powder shooting, very knowledgeable and talented.
CCI 10's are the worse of the lot IMO and in their size comparisons to all of the others. Bought some once long ago not knowing the size comparison. To tight a fit to set snugly over the nipples of all I had. In order to seat them I had to gently push them on with a wooden dowel to seat after trying their fit. Did so on empty cylinders as I was fearful of a discharge except for the first loaded revolver I tried em on. Pried em off. According to what I've been told and read, the CCI 10's fit on a few small caliber cap guns with smaller nipples than their bigger cousins. Tracks chart shows that to be the case. My first cap gun back in 1972 was a disaster with caps. All available were some Italian caps in a red plastic 'tin'. They were $1 per 100. I had to pinch everyone to stay on the nipple and upon firing several unfired ones would fall off every time and cap fragments were always falling into the innards. The Ol Eruoarms '51 Navy Colt in 44 was an eye opening experience into percussion revolvers. IMO Rem #10's if available are the best of the lot with CCI #11's a close 2nd. Others I've talked with and what I've read agree also. But sometimes ya gotta go with what ya can find. Well I wrote a book and didn't have any intention to but hear ya are.
