primer failure

[dieseldoc]

Have CCI 450 primers (new supply) out of 10--- four would not fire, cycled bolt and three of the four did fire. Question is what do you do with a loaded round that has been strike (heavy) and didn't fire???

Charlie

 

[trueblue]

Good question. I have not run into this, but I guess I would pull the bullet out and dump the powder, and start over.
Sounds like you might need to check your primer pin depth.

 

[shootinfool]

I have only had this sort of thing happen to me one time in the past. It was one round and it was more like a delayed fire. I pulled the trigger and heard the firing pin hit...nothing for a few seconds. I actually thought that i had not picked up the bullet from the mag at first. A few seconds later....BOOM! I can only guess that this was my fault in not paying attention enough during the cleaning of the primer pockets and flash hole and left a piece of corn cob in their from tumbeling. Needless to say, I check and double check and then tripple check before I do anything else now. Dont know if this is your problem but it is an Idea. Pull the bullets and see what is going on. dump the powder and see what it looks like and then pop the primer and see what it looks like.

 

[Mikecr]

CCI's require better strike than sufficient for others. But they are good primers, and you can work out the bugs in your striking with them.
Explosives react to peak energy. Not just amount, but amount applied at once.
This is why you can slowly crush a primer completely without setting it off(but not always).
And you might have normal dimpling on the back of your primers, but they can still fail to fire.

-It's cold out, the bolt/pin lube viscosity is slower. This means energy applied slower.
-Your pin depth or spring might need adjusting. It might not be traveling with sufficient speed on strike, or far enough to crush the primer pill in a way that sets it off. I've found that there can be a sweet spot between too deep, and too shallow for a primer/cartridge/action.
-You might not be seating primers to the bottom of their pockets, at a slight pre-crush amount. This allows the primers to move on strike, reducing peak of the energy applied.

People try different primers during load development until happening into a combo that works best for some reason.. No consistency to this.. In fact, this is just opposite of a method.
I suggest that ANY primer can work just as well, once the bugs are worked out.

 

[RT2506]

It sounds like you are either not seating your primers deep enough or you have a too light of a firing pin spring.

 

[Trickymissfit]

I'm assuming you got a good strike on the primer face. Would be interesting to see just how far below the case head the primer is seated (.005" below is about right).

You need a good bullet puller to take the round apart. The Hornaday or the Forster both work well. Dump the powder in the trash can! Stand the case upright in a loading tray, and fill the cases up with warm water (not hot) and let them set for a couple hours. Now very carefully decap the primers. I've heard of folks doing this with WD40, but water has always worked well for me. The idea is to kill the primer, and then decap. I'd also be looking at how I prime the cases, as you mabe contaminating them before pressing them into the case body.
gary

 

[dieseldoc]

First of all, thank you all for the input and in check out the ones that didn't fire this is what I found.

Looking at the hit on the primer it looks to be much lighter that the others that fired.
Flash holes were clean, no burrs.
Loaded case, in checking I found primer flush with bottom of case.
Removed fire pin, check no excessive lube.

Results of check I believe the problem was my seating of the primers were not deep enough and In fact the firing pin was pushing primer in and this what caused lite hit.

Have loaded up more for test, seated below case at .005 and found problem went away at the range today.

Again thank you for the help.

Charlie

 

[Trickymissfit]

First of all, thank you all for the input and in check out the ones that didn't fire this is what I found.

Looking at the hit on the primer it looks to be much lighter that the others that fired.
Flash holes were clean, no burrs.
Loaded case, in checking I found primer flush with bottom of case.
Removed fire pin, check no excessive lube.

Results of check I believe the problem was my seating of the primers were not deep enough and In fact the firing pin was pushing primer in and this what caused lite hit.

Have loaded up more for test, seated below case at .005 and found problem went away at the range today.

Again thank you for the help.

Charlie

I think you priming device is the problem here. Hand held priming devices often put primers all over the place. I use a K&M and the one on my Forster press, but have several others gathering dust. One thing about hand priming tools is that you have to learn a certain feel in seating the primer. Some guys say it's in the crush, but I'm now convinced to your far better off seating to a consistent depth
gary

 

[Mikecr]

Some guys say it's in the crush, but I'm now convinced to your far better off seating to a consistent depth

IT'S BOTH

Seating to a set depth allows consistent strike, but primer ignition can vary with the resulting crush variance. So pocket cutting to a set depth is a prerequisite here. The next is actual primer height(they all vary). Having a K&M primer seater, you should be aware of their indicated model that zeros out variance in pocket depth AND primer height to achieve correct crush.
With same pocket depths, same crush, and best adjusted strike for the primer, I think proper seating is pretty much covered.
But one other factor, is time. Seated primers tend to back out a bit within a few days, and there has been recent testing that showed this continuing for a few weeks(at an ever dropping rate).
I've seen this enough with Lapua, Norma, and Tubbs brass. But I haven't yet tested for specific impact of it from day to day.

There is more to primer firing than merely 'sufficient'..

 

[Trickymissfit]

IT'S BOTH

Seating to a set depth allows consistent strike, but primer ignition can vary with the resulting crush variance. So pocket cutting to a set depth is a prerequisite here. The next is actual primer height(they all vary). Having a K&M primer seater, you should be aware of their indicated model that zeros out variance in pocket depth AND primer height to achieve correct crush.
With same pocket depths, same crush, and best adjusted strike for the primer, I think proper seating is pretty much covered.
But one other factor, is time. Seated primers tend to back out a bit within a few days, and there has been recent testing that showed this continuing for a few weeks(at an ever dropping rate).
I've seen this enough with Lapua, Norma, and Tubbs brass. But I haven't yet tested for specific impact of it from day to day.

There is more to primer firing than merely 'sufficient'..

I never noticed this, but I'm going to run a test tonight on about a hundred 6/250AI rounds I have built up. These are about 20 months old, so we sould see something here. I have a little hand held gauge I built (extremely simple and on the cheap!), plus another setup to measure primer pocket depth. Both are similar in design, but of course setup for different depths.

My K&M tool does not have the dial indicator attatchment, and sometimes I wish it did. When I use this tool I do it by feel, rather than depth (my hands are too messed up to use a Sinclair tool).
gary

 

[Aldon]

What about the Acrylic Primer sealer?

Does anyone have experience using it and if it is not detrimental in some way, would it add the benefit of reducing or eliminating the primer from slipping after it cured?

 

[Trickymissfit]

IT'S BOTH

Seating to a set depth allows consistent strike, but primer ignition can vary with the resulting crush variance. So pocket cutting to a set depth is a prerequisite here. The next is actual primer height(they all vary). Having a K&M primer seater, you should be aware of their indicated model that zeros out variance in pocket depth AND primer height to achieve correct crush.
With same pocket depths, same crush, and best adjusted strike for the primer, I think proper seating is pretty much covered.
But one other factor, is time. Seated primers tend to back out a bit within a few days, and there has been recent testing that showed this continuing for a few weeks(at an ever dropping rate).
I've seen this enough with Lapua, Norma, and Tubbs brass. But I haven't yet tested for specific impact of it from day to day.

There is more to primer firing than merely 'sufficient'..

this is a post everybody needs to read!! I just rand a check on a hundred primed cases, and was in a shock. I found primers that had backed out to within .0015" of the face, and even worse in one big lot of 45LC brass. I'll reseat the 45's as they are unloaded. One lot of 35 Rem. was also pretty bad, and I'll redo those as well. Yet I check a box of 6mm Reming cases that had the primers exactly where I seated them. Figure that one out! (did them a couple years ago)
gary

 

[dieseldoc]

this is a post everybody needs to read!! I just rand a check on a hundred primed cases, and was in a shock. I found primers that had backed out to within .0015" of the face, and even worse in one big lot of 45LC brass. I'll reseat the 45's as they are unloaded. One lot of 35 Rem. was also pretty bad, and I'll redo those as well. Yet I check a box of 6mm Reming cases that had the primers exactly where I seated them. Figure that one out! (did them a couple years ago)
gary

Gary:

Have been working also on what could be causing failures and run across information by James Calhoon Varmint Hunter Mag. Oct 95 on specs of primers ,cup thickness,diameter and height for small and larger rifle on CCI,Federal,Remington and Winchester.

I have a PDF file I will sent to you as a PM as I can't find how to post it here.

Charlie