Why am I having these primer ignition issues?

I can't see it in your picture, but it could be that you are not seating them deep enough. They should be fully seated in the bottom of the pocket. If this is new brass, or you are using another method of seating primers i would look at some of them before loading to make sure you have positive seating.

You may not be pre-loading the anvil during seating. Primers require a pre-load to function reliably. Not going off on the 2nd attempt may indicate something else. Break it down and see if the anvil is in place and there is primer compound pelt in the cup. The proper depth is when the anvil is pre-loaded. This can vary from piece to piece. Those who go by depth eventually run into problems if a pocket is deeper.

This is a very interesting article on primers:


Mysteries And Misconceptions Of The All-Important Primer

http://www.shootingtimes.com/2011/01/04/ammunition_st_mamotaip_200909/

So, I believe that you are not seating your primers properly on your Dillion 550B. The referenced article states that the most common cause of misfires are high primers. You have to seat the primer such that the anvil is firmly set, and the bridge distance is set. As the article says:


The real story is that Boxer primers leave the factory with the anvil higher than it would be when seated in a cartridge case. Seating so anvil legs touch the bottom of the pocket lets the anvil tip penetrate into the pellet of mix. The nearly universal recommendation of having the primer cup bottom 0.003 to 0.005 inch below flush with the case head exists to set the proper amount of priming mix between the cup and the anvil tip.


This critical distance is known as the bridge thickness. Establishing the optimum thickness through proper seating means the primer meets sensitivity specifications but does not create chemical instability. However, failing to set the bridge thickness through proper seating depth is the number one cause of primer failures to fire. The bridge thickness is too great with a high primer, even one whose anvil legs touch the bottom of the pocket.

Sometimes a second firing pin strike will ignite a high primer, the first strike seating the primer. But, sometimes that first firing pin strike breaks the primer cake and after that, nothing short of flame and heat will make that primer cake ignite.

Try a different brand of primer, see if it makes a difference.

In my reloading career I have only had one problem with primers (after I learned to completely seat primers to the bottom of the pocket). That was with one make of primer and one gun. I was using Winchester SP primers in 9mm brass in a striker fired gun. The gun fires all other make of primers and the Winchester primers worked in other guns. I finally discovered that if I seated the primers and gave the lever an extra bit of ummmph! I could get 100% ignition. This is, as I learned later, is called "pre-loading" the primer. I just seated the primers and then added a bit of force to slightly "squish" (pre-load) the primers. I have had no problem with failures to fire since then...

The Dillon priming system is excellent and will load tons of ammo with out a problem. It requires attention where the primer arm slide stops against the frame. Small amounts of carbon can stall the alignment of the primer seat. This allows a shallow seating in the cartridge. I use a tooth brush and occasionally dust the primer seater slide and pocket. A small amount of graphite can help also. good luck.

The most common cause of a primer not going off is not being fully seated into the primer pocket. In the photo below it shows a primer before being installed. The anvil protrudes above the cup rim. When a primer is properly seated the anvil is pushed into the cup and should end up flush with the rim of the cup.

yup, the face of the primer should be flat, not round like the doughnut-shaped primer in your first pic. i squeeze as hard as i can using my lee autoprime when seating primers. i squeeze so hard that i have to use a glove on my right hand to prevent getting a blister.

on a dillon, i'm sure you could crush a primer with all that leverage, but you should still seat them hard enough to get the flat across the face.

luck,

murf

lezmark said:

Wow, thank you all that replied. I guess there is always something new to learn and this one kinda came out of left field for me. I have been shooting matches and now have to figure out what to do with the few hundred rounds that apparently are not seated correctly. I would hate to have to pull that many...

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A few hundred would not take very long. Pull bullet, dump powder, seat primer, reload. I'm not sure what else you would do with them other than use for practice with knowing you might have a fail to fire.

Or, I would set aside those reloads for use when practicing for competition or "plinking". Load up some more, making sure they are seated properly, for use when competing...

Lemonade from a lemon statement of the day..Misfiring loads are good for learning trigger control and jam clear practice!

murf said:

yup, the face of the primer should be flat, not round like the doughnut-shaped primer in your first pic. i squeeze as hard as i can using my lee autoprime when seating primers. i squeeze so hard that i have to use a glove on my right hand to prevent getting a blister.

on a dillon, i'm sure you could crush a primer with all that leverage, but you should still seat them hard enough to get the flat across the face.

luck,

murf

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Actually that's not true, seating with too much pressure can cause problems just as seating with too little pressure can.

Seating is done most reliably with a hand tool and not a press because you can feel when the cup contacts the bottom of the primer pocket, several people have mentioned "preloading" which is actually the process of compressing the primer cup and anvil the proper amount, but it's impossible to do consistently with a press.

As shown in the pictures of the primer, the anvil sits a little higher than the cup before you seat them. To properly seat a primer the anvil needs to be compressed to the same height as the cup (preloaded). When you seat a primer the anvil contacts the bottom of the pocket first and as you press harder you compress the cup and the anvil until the cup contacts the bottom of the pocket. If you compress too much you will flatten the primer cup and you will destroy the preload condition.

Primers ignite due to the shock of the firing pin strike. That shock is transmitted through the primer cup in to the priming mix. The priming mix is then "bounced" (for want of a better word) between the cup and the anvil which then ignites the priming mix. If you don't seat the primer deep enough then the mix isn't going to be as sensitive to the shock of the firing pin strike and you can get misfires, usually they will ignite with a second strike. If you seat the primer too deep (compress the cup and drive the anvil in to direct contact with the cup) then you can get misfires too but you usually wont get the primer to ignite with a second strike, the primer becomes insensitive due to the mix having been displaced away from the contact point between the cup and the anvil.

With a press you have so much mechanical advantage that you can't really feel when the cup contacts the bottom of the pocket so you have a tendency to use too much pressure and you increase the chance of making your primers insensitive. With a hand priming tool, if you uniform the primer pocket so that the depths are consistent, and with practice, you can feel when the anvil touches the bottom of the pocket and you will also feel when the cup contacts the bottom of the pocket, you can actually feel both contacts. Consistent preload and seating of primers helps reduce muzzle velocity spreads and deviations.

I'm sure anything is possible, but never once have a had a problem from seating them too hard. I've definitely had problems from not seating them enough.

Anything below flush should go bang if it is hit hard enough. Exactly flush, or above flush can and will lead to problems.

I don't know exactly how the priming system on a 550 works, but if it is like that on a 650, the seater stem can start to back out eventually, and can lead to high primers. I ended up with a few hundred rounds with high primers once because of this. I just ran them through my hand primer tool to get them seated the rest of the way; I tightened up the seating stem on the 650, good to go after that. You could add a dab of loctite if that is the problem and happens again... so far I have not had it back out again.

Walkalong said:

I have posted before that it is hard to "crush" or damage a primer by seating it too hard. It is much easier to go too soft and have failures. Seat them good and snug.

After many years of use my RCBS hand primer starting having trouble seating large pistol primers all the way. I had to make a new stem for it. Seats them fully again.

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I had a hand primer that malfunction and went past the stop causing the primers to flatten and actually crush. I didn't realize this was happening until I ran my finger over one of the cases to be sure they were deep enough. I had about 15 like that. I decided to load them anyway just to see if the crushed/flattened primers would fire. Strangely enough not only did they fire they were very accurate too. (223 ammo in a bolt action rifle) What I took from this is primers are much tougher than even I expected. Sorry no pictures but I can tell you these primers were very flattened.

I agree you might not be seating the primers correctly. The problem started when you went from hand priming to on press priming where you can't feel the seating as well as when you hand prime.

I personally don't buy into the theory that hand priming is the way to go. The ammo manufacturers mechanically seat their primers. The primer system is very forgiving with the exception of not seating enough. The presses have leeway built into them to handle variance in pocket depth and primer cup. It is easy enough when setting up the press to sample some of the primed cases by checking with a hand primer or even a single stage press for "feel" of complete seating. If I change primer type or case type I always sample test before loading 1000's of rounds at a time. I have never in many 10's of thousands of runs from my progressive press had a fail to fire. Make sure they are seated by sample test the primer seating process. As far as consistences the chronograph shows they are with the progressive press doing all the work.

I have been loading for many years and I have never had a fail to fire.
I have used press priming, bench priming and hand priming at different times, I disagree with the fact that you can't feel the primer seat with anyone of these methods. If you take your time and don't heavy hand things you can feel it seat. you don't have to flatten them to have them seated either.

walkalong,

there is no way to get rid of the rounded edges on a seated primer unless fired with extreme overpressure (i've done it with a 357 magnum load and stopped immediately). what i'm saying is to seat hard enough to flatten the face, not the edges. the small pistol primers are .020" thick. that's almost twice the thickness of the case neck. i don't think a hand priming tool is going to come close to "crushing" a primer. i'm for consistency, and always want to err on the heavy side when it comes to primer seating.

macgrumpy,

i have had no primer issues with this method, so i'm going to have to disagree with you, here.

murf