just opened a bad can of CCI caps. I had several cans in my last batch that the caps were a dull color. they all seemed to work fine so i didnt think much of it. this last can that i just opened the caps were dull color. looks like copper instead of brass. i was getting failure to ignite every other cap. I put brand new nipple on and same thing happened. Thought maybe my mainspring was getting weak???? anyways i had a can of winchester caps on hand and tried them. 10 shots no missfires..