Ocassional failure to fire

[beefyz]

I have a Marlin '94 CL in 32-20. Upon reloading for it using Rem 1 1/2 primers I noticed a few pierced primers. I stopped using the 1 1/2s. However, I noticed what appeared to be "slag" or something that looked like burnt powder on the bolt face and on the pin hole? It easily cleaned off the bolt face with a few brushes. But now I appear to have another problem. I keep getting occasional failures to fire. Out of a box of 50, around 10 or so will not fire on the first strike. I rechamber, fire again, and 6-7 will go off. The final 3-4 will not fire. Of the original 10, the first pin strike is very light; very slight indentation. The ones that don't fire after 3-4 attempts by now have a good indentation on the primer. They just didn't go off. Primer selection makes no difference; either WSP or CCI400s are being used. I'm wondering if that first incident with the 1 1/2s didn't break off a very small part of the primer leaving me with a just barely adequate pin. What says you? NEVER have had a broken pin on any of my firearms so i'm not sure.

 

[243winxb]

The metal from the pierced primers may now be in the firing pin channel. It needs cleaned?? Or primers are not seated fully? Or you need a new Hammer Spring / Mainspring or/and firing pin.

 

[Stony]

Sounds more to me like a problem with seating your primers. They should be seated firmly against the bottom of the primer pocket. If not, the first strike will only seat the primer the rest of the way occasionally, and the second strike will fire it. Generally speaking, a pierced primer won't leave any material floating around, they will just leave a tiny pin hole in the center of the primer.

 

[rcmodel]

That.
Not fully seating the primers is one cause.

And the previous pierced primers very well my have eroded the firing pin tip off.

243wiinxb's comment on primer particles blown into the firing pin channel is also a very likely suspect to check out.

rc

 

[beefyz]

Thanks guys for the comments. I always clean out primer pockets every time and have seated appx. 12,000 primers over these last 5 yrs in a number of rifles and can only remember 1 primer that might have been defective and failed to fire. Why so many in this one gun or caliber/case only? Am I sloppy just in seating primers in the 32-20?
With my little knowledge on this subject, I also suspected possible pin erosion/slag in the channel or springs, but I just wanted to make sure there wasn't something else I didn't know about. Ironically, i'll be reloading another 150 or so of these this morning and will pay PARTICULAR attention to my seating of primers, but if it happens again, i guess its off to a Smith. Thanks again for helping me out. I'll post with results either way.
z

 

[4v50 Gary]

If it's not the ammo (factory ammo should be reliable), then clean the firing pin, firing pin channel and the spring. Buildup of deposits and grease can impede the forward momentum, making the pin's impact lighter than needed.

 

[Kp321]

I had exactly the same problem with a Springfield Range Officer 9mm. Using the ammo I loaded several years ago with CCI primers (I think ), it would act like a hole punch and the "hole" would end up in the firing pin channel. It would fire two or three then the stacked holes would cushion the blow and cause FTF. A dry fire would clear things up for a few more rounds. I could feel a small raised ring around the FP hole. Very small, less than .0005". I dressed the breech face with a fine stone and switched to new loads with WSP primers and have had no more problems. I have not gone back and tried the old ammo, maybe next range trip.