mike,
i did not encounter the same exact problem as you but with winchester primers i could not close my pursuit. i called traditions and they said they were having breech plug problems. you should either be able to get a replacment breech plug which is a better fit or try differernt primers i think they said they tested the gun with remingtons. but find out for your self when you call them. your gun is probablly not getting a positive lock when closed due to the primer & breech plug fit. you should be able to notice a differernce when closing the gun withe a primer seated compared to being empty. good luck with it .