On my Knight Wolverine II LK-93 it is a #11 cap ignition. I have capped it and walked all over the range and set the gun down in various positions and never had a problem with the cap backing off. On the other hand right before I shoot I take my thumb and push the back of the cap to make sure it is well seated. If the caps feel loose like they are sliding, then lightly just squeeze the back of them together a little, not until they are deformed but just to change their shape a little. Many times that it all it will take to hold them onto a nipple good and tight. I have done this for years with my sidelocks when I hunt with them.

On my CVA Staghorn I shoot musket caps and I have noticed they are more prone to sliding off. Although again, I take my thumb to them and have not really had a problem.

The 209's once their on, their on. If they are falling out check and make sure the wire band that goes around the 209 nipple is not broken. Usally you have to use the decapper or a good strong thumb nail to get them to back out.

One advantage of shooting #11 caps and musket caps is you get less crud in the breech. Also some people report a crud build up with Triple Se7en and 209 primers. I think it is because they are using too hot a primer and too much powder. When I shoot the Staghorn with the musket caps I have not really noticed a "crud" build up. Besides when you swab you are taking that fowling for the most part out of the barrel.

I have been shooting Goex out of my rifle for the past month and really like it. The rifle seems to shoot real good with Goex FFFg and fowling is really not all that big an issue.

Good luck with your rifle your going to like it.