Firing Pin Lightstriking Primer?


January 5, 2005, 03:04 PM

I need some help here. Last night I loaded up 36 rounds of .44 Mag. with Hornady 240 gr. HP-XTPs and 22.2 grains of H-110. This morning when I went out to shoot them, two out of the six rounds in the cylinder failed to fire. It looked like the firing pin had left a very light mark on the primers -- so I am wondering if it is too lightly striking them. The rounds that fired looked totally normal with their primer indentations. This leads me to believe that either my gun is light-striking the primers, or that my gun is functioning normally and the primers are indented more when the pressures of the round make it slam back into the firing pin.

Failures to fire such as these have never happened to me before. I am extremely careful with my reloading, therefore I am almost certain there is nothing at fault in it itself. Could the primers be too hard for my pistol to ignite? I am shooting a S&W 629-5 and I will send it back to the factory for repair if need be. The disconcerting thing about all this is that we brought out my brother's Super Blackhawk and it fired twelve of the reloads without a hitch -- two of which were the one's my 629 had failed to fire with. One difference I did notice between the two guns was that the Blackhawk's firing pin protruded farther from the faceplate (or whatever it's called) of the revolver -- in other words, it would protrude deeper into the primer when a round was being fired.

What should I do here? I am kind of thinking I need to send my pistol to S&W to fix. Should I do this, or is there something I am missing here? Thanks a LOT for all advice as this has me quite concerned!


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January 5, 2005, 03:23 PM
A third option may be that the primers weren't fully seated, and bumped forward as the firing pin hit, absorbing some of the pin's energy.

What primers are you using?

Has this failure to fire/light strike happened before with this gun?

January 5, 2005, 04:00 PM

Thanks for the response. The primers I am using are CCI 350 large pistol magnum primers. I have never had this problem before whatsoever. You pointed out a good idea about primer seating, however I do not believe it is that I am not fully seating them as I seat the primers quite hard and make sure they all are below the case head.

This has me quite confounded because I have never experienced this with my guns or reloads before. Any other ideas? Thanks again for your help!


January 5, 2005, 04:36 PM
CCI primers have some variation in the cup size (both width and height) that can lead to seating issues; run a batch through a mic to see. They're also tough buggers!

In my 44 Mag loads (24gr of H110 behind a 240gr XTP; a good solid crimp is your friend ;) ) I use Winchester primers (the combo std/magnum ones). They're a bit softer than the CCIs, and I don't have any problems lighting them off with my Redhawk that's had the action lightened up a bunch. CCIs gave me the occasional (1 in 100) failure, but that was probably seating.

Another primer I've used with great luck in my revos are the Federal 155, easiest igniting of the bunch, but they tended to flow with max loads out of my lever gun.

January 5, 2005, 04:42 PM
The mainspring screw should be tightened all the way , it isn't a trigger pull adjustment. Primers may be different in thickness and in hardness, you may have gotten an extra hard batch !

January 5, 2005, 04:50 PM

Thanks again for the response! Your help is GREATLY appreciated. So. . . your saying it either has to do with the strength of the primer or the method of seating -- right? You don't think it has to do with the actual revolver? I just went out again and had three more light-stikes in a cylinder and a half. This should not be normal even for the CCIs should it? Do you think I might have seated them too hard? I pressed them in there pretty good, but I usually do this when reloading. If it were you, would you send it to the factory to check out? I just don't know quite what to do. It seems like even if the CCI primers are hard, I should not be having this many light-strikes. What do you think? Thanks again!


Black Snowman
January 5, 2005, 04:57 PM
You won't get light strikes for seating too deep unless the primers are way out of spec and seating very deeply (which you'd notice).

Try factory ammo again or old reloads that were OK. If they're fine it just might be that lot of primers are very very hard.

January 5, 2005, 05:01 PM

Thanks for the idea, however, I was wondering which one exactly is the mainspring screw? Is it the one at the base of the grip that contacts the mainspring?

Black Snowman,

Thanks for the response! I'm gonna try to pick up some factory ammunition today to see if that remedies the problem.


Thanks for all the help!! I can't tell you how much I appreciate it. I can always count on The High Road!!!


January 5, 2005, 05:03 PM
It may have to do with the primer "hardness". Or seating (not deep enough, if the primer isn't seated in the pocket, it will move forward as the pin hits it).

Or it could be the gun, but as this has not been a problem, sending it off to SW for "repairs" may not resolve the issue (the gun may very-well be in spec). And mete's comment is well considered.

CCI primers are widely considered to be the hardest to ignite (then Remington, then Winchester, with Fed being considered the the softest/easiest).

It sounds like you're seating the primers fine. So I suggest a different brand of primers. This is just another part of sorting out the load your gun likes best, and primers are one of the variables.

Let me know if you need further clarification (I'm not thinking/writing too clearly today) and keep us posted!

January 5, 2005, 05:47 PM

I REALLY appreciate your taking your time to help me out here. I was getting very stressed out today because this problem is new to me. I got all excited and automatically thought it had to do with the gun, but your advice has calmed me down greatly.

I did not know this about the CCI primers being the hardest type of primer. This being the case, I think I probably just got a harder batch. I'm going to try to load another batch with the federal primers instead.

You've been very helpful and I appreciate it greatly!! I'll let you know what happens when I get the next batch loaded. Thanks again!


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