Well, I finally bought a 209 ignition system for my older knight wolverine. And I guess it is right what they say. I used to get 2" groups with 95gr of pyrodex and 240gr XTP. Now with the 209, I am getting 4" at 100 yards. I tried powerbelts, 240gr XTP, 250gr Knight barnes, and combination with 100gr of pellets, 90 to 110gr of loose pyrodex, 90 to 110gr of goex with all bullets. I guess its right that with a hotter primer accuracy can suffer.

2 inches is minor compared to the gun firing every time you pull the trigger

Idon' t think 2' ' difference is acceptable,there must be a better alternative.Cecil at persion bullets has modified a encore/omega breach plug to shoot a .22 hornet shell with a small rifle primer.

I am not happy with it, but will accept it. I sure don' t feel very comfortable at a 100 yard shot now. Do you think I need to go up in powder or down, I worked with 90-100gr of pyrodex.

From what I heard, thats typical, but part of the trade off for having reliability.

I have yet to have a misfire using RWS #11 caps (they call them 1075 caps). But I only shoot loose powder.

I don' t want to go to the expense and trouble of ordering one modified from Cecil
but if T/C would come out with a breech plug to shoot #11 caps in my encore I would get one.I bought a MK 85 the first year they came out and a ruger the first year they came out,still have them and I have never had either one to miss fire using 2 pellets of pyrodex,2 pellets of clean shot or up to 120 grs of pyro and clean shot in either one,I have used the german caps ,remington and others.
Had a knight disc year before last and the blow back was pretty bad,more than I get shooting the ruger and knight using the #11 caps.

According to Ned Roberts in the Muzzleloading Caplock Rifle, the old-timers PREFERRED " weak" caps for target shooting, because they gave better accuracy. I have a primer adapter that allows you to shoot a caplock using small rifle primers instead of caps. One time I was doing some chronographing of a Maxi-ball load in a .45 rifle, and with the primers, extreme velocity variation exceeded 100 FPS! I installed a regular 1/4X28 nipple, and started using CCI No. 11 caps. Extreme variation dropped to 11 FPS with the SAME powder charge and bullet!! This seems to support what you discovered.

I switched my CVA to 209 primers, because I hade a couple misfires with #11`s.
Though I admit the misfires were not fresh loads, they were only a couple of
days old and well taken care of (not been in rain or major temp change).
I dont change my load after each hunt, I use the same load for several days hunting,
provided the weather was good etc.
I havent noticed any change in my groups but if I did I would accept a small loss
of accuracy just to know that baby is gonna go boom when I squeeze the trigger.[&:]

I agree that with the 209' s, misfires don' t seem to happen! Of course, when hunting, this is very important!