A primer/ firing pin related adventure I'm sure.

The cases that I was able to purchase for my 25-20 SS rifle uses a small rifle primer. A friend of mine has a whole case of Federal magnum small pistol primers that he bought by mistaking them for small rifle primers. Wonder how they would work out in a Stevens 44 in 25-20 SS. Being a magnum they should have a thicker cup.I had a hell of a time trying to get that rifle to shoot accurate. Tried several different powder,3 different primers, and 5 different bullets / weights. An inspection of the bore showed little wear and a near new appearnce. The over all look of the rifle suggested that it has spent its life in a closet. It looked to be better than 95%. However it just would not shoot accurate, and was a very wide spread in the chronograph readings with everything I tested, about 350 to 400 fps. At the end of my rope with that rifle I noted that the back of the firing pin was really battered and the point of the firing pin also looked chipped. Even the face and back of the breech block looked beat up. A gunsmith friend took the action apart and found that the extractor had a crack and he went on to say that he noticed the firing pin hole through the breech block was way over size and sloppy. It was not a job he wanted so I packed the rifle up and sent it to John King for rehab. It's still there awaiting repairs. I'm willing to bet that messed up firing pin and hole through the breech block was some of the cause of poor accuracy with this rifle. By stricking the primer with more or less force from shot to shot could have been contributing to the accuracy problem. Also the firing pin would twist in the breech block and when it did the burr on the back prevented it from having a full range of travel through the block. I've been told that John King's work is top shelf by John Taylor. If Taylor gives King a seal of approval then King's work should be outstanding. I will report on this when my rifle returns. Sendaro

What is the proper spring tension on the CPA or does it vary with the type of primer and powder?  Does having too much tension cause wear on the set trigger mechanism? I have mine set to where it "feels about right" which is not very scientific. It functions and shoots very well at this setting using small rifle or pistol primers.  Accuracy is much better with the pistol primers with the load I'm using but could that be a function of hammer fall as well as primer type? 

John Shaw