Bad lot of primers?

[swedgon]

I don't know if this belongs in the Revolver forum or here. But here goes. I shoot a lot of reloaded ammo. All reloaded by me. Usually 300 or more rounds a week practice for NRA Action pistol. I shoot a 686 S&W revolver. It is modified for a lighter trigger pull but the hammer hits the primer harder than some newer unmodified guns I have. I shoot Winchester small standard pistol primers. I am in the last 1,200 of a 5,000 round brick. I started this season with new Federal brass. For the last eight weeks or so I have been getting one or two misfires a week out of aprox. 300 rounds a week. I use a Dillion 550 for all my ammo. I have even tried using a Lee hand primer. When I get a misfire there seems to be a light hit on the primer. It fires when shot the second time. As an experiment, last weekend I used 200 rounds of new Starline brass and a different lot (batch number) of Winchester primers. Not one single misfire. Where do I go from here? Bad primers? Dirty primer pockets in Federal brass? I have never cleaned primer pockets on handgun brass.

Thanks in advance for any help.

 

[crowbeaner]

You could be experiencing the misfires because of ash buildup in the primer pockets. I'd try cleaning the pockets on 100 and see if the misfires continue. It may be time to use the brush on them because the ash is preventing the primer anvil from bottoming out in the pocket. CB.

 

[Voyager AL]

same problem here, change brand of primers at next visit to Sportsmans warehouse

 

[Mal H]

I'm going with the dirty primer pocket theory also. Even though a light firing pin strike would normally indicate a revolver problem and not a primer problem, however, given the results of your experiment, I think the firing pin energy is going into seating the primer further into the muck. The second hit fires the primer.

In truth, your new-brass experiment was flawed since you changed two variables. You don't really know if it was the new brass with clean pockets that fixed the problem or whether it was the different batch of primers.

 

[jdmick]

What is the lot # of the primers?

 

[snuffy]

I shoot a 686 S&W revolver. It is modified for a lighter trigger pull but the hammer hits the primer harder than some newer unmodified guns I have.

I'll take a WAG here, all revolvers I've ever seen that had the trigger pull modified, had the hammer spring lightened. That results in a lighter hammer strike. Just how did you determine that the hammer strikes the primer harder?

I've never subscribed to the theory that primer residue can cushion the primer anvil enough to prevent ignition. As long as the firing pin hits with proper force, a primer will detonate.

 

[WIL TERRY]

You Can Take This To The Bank !!!

If a primer did not fire the first time you hit but did do so the second time it was struck, YOU DID NOT HIT IT HARD ENOUGH THE FIRST TIME !!!
Now, figuring out why this is so can try the patience of a saint. Most of the time it is a gun problem. All most all of the time it is a gun problem it is caused by the gun owner messing with the springs; TAKE THIS TO THE BANK TOO !!!
Put the original springs back in the pistol and run several hundred rounds through it and see how many misfies you get then.
I will entertain minor wagers on this....

 

[Travis Two]

I'd say the problem lies more with the firearm than the primers. The fact that you hand primed and machine primed and are getting the same results but that the primers are going off on the second hit seems to suggest that maybe the springs have gotten weak in the gun and due for replacement. Check the tension screw on the main spring to be sure it didn't work lose.
Still I would check the primer mechanism on the Dillon to be sure that it didn't come lose and that you aren't getting inconsistent seating on the primers.
After loading the rounds stand them up on end to see if the primers are being fully seated on a consistent basis. A high primer won't let the round sit flat and would wobble.

 

[swedgon]

I'll have to get back to you on the lot (batch #) of the Winchester primers.
As to a way to test how hard one gun hits the primer compaired to another; I use the old lead pencil trick. Empty gun, cock hammer, drop lead pencil down the barrel, point barrel up, pull trigger. I used a stock model 66 and another 686. Also a new M&P S&W. My 686 with the modified trigger sent the pencil quite a bit higher than these other guns. Try this with a 1911 with a 20 lb. hammer spring and you might have to paint something.

 

[Mike Irwin]

If this started suddenly, take a look at the strain screw on your gun.

Is it screwed in tightly?

If it has started backing out it could be reducing the hammer speed just enough that it's giving you misfires.

 

[TWB]

It would be logical that if the primer fires on the second strike, the primer itself is okay. The priming pellet would have to be functional, the anvil would have to be in place, and the the cup would simply need to be stricken hard enough to initiate the explosive.
About everything that will cause a functional primer to fail is listed in the above replies. The only thing different I can think of is a defective primer pocket. This may not apply to your brass, though, if it has worked fine in the past.
All these things are fixable. There may be other things to cause the problem that I missed, but it would seem that the primers are functional. Please let us know what you finally discover as being the problem.

twb

 

[Sevens]

Why not try taking ten empties (or a hundred?) and hand priming them so ridiculously out of spec that you can barely chamber them -- on purpose? Have those primers simulate being primed over dirty pockets, and thus not seated to full depth, and see if your modified revolver will detonate them on first try. Not loaded rounds, mind you, simply empty primed cases and NO barrel obstructions.

If your 686 is typically modified you may also be using a shaved hammer which increases hammer speed, but has lost some weight and in the process, mass, which the gun was originally designed to use.

I would also take the camp of the modified revolver being the problem in this scenario.