primers not igniting in some 35 Whelen rounds?

[p5200]

All primers in the re-sized 30-06 brass all fired good that were fired. The 35 Whelen Hornady brass, was the only thing that failed to ignite on some rounds the 30-06 brass is Federal my guess is difference in primer seating depth it seems, the primers aren't quite as deep in some of the 35 Whelen brass. Could that cause the misfire problem? When I stand some of the rounds on a flat surface, they kind of wobble around when lightly tapped? Can the depth be measured with my digital calipers? Thanks for all info!

 

[ballman6711]

If they wobble your primers need to be seated deeper. They should be seated below flush, no wobble when set upright and lightly tapped.

Yes, you can use your calipers to measure how far below flush they are seated, using the bottom/back end of your caliper as a depth gauge. Others can probably explain it better than I ever could hope to.

Did you try firing the "failed to ignite" rounds a second time? Sometimes if the primer isn't seated deep enough the first firing pin strike will seat it fully and the second strike will ignite it.

chris

 

[p5200]

Yes we tried twice I suppose, I will have to pull the bullets/powder and reload them? I used Wolf primers maybe, I should try the Federal primers I have! thanks!

 

[rabid wombat]

On measuring, skip the first minute of the following. It gives a visual on measuring depth.



As @ballman6711 says, the 35’s do not sound like the primers were set appropriately.

 

[.308 Norma]

the primers aren't quite as deep in some of the 35 Whelen brass. Could that cause the misfire problem?

Absolutely, positively yes!

Sometimes if the primer isn't seated deep enough the first firing pin strike will seat it fully and the second strike will ignite it.

What ballman6711 said. If I've seen one, I've seen a hundred posts about how "deep" to seat primers. Seat them to the bottom of the pockets and they won't require second firing pin strikes to set them off.

 

[p5200]

Thanks, seems I read somewhere they should be about .003-.004" below case sound about right? and, could this be the reason for the misfires?

 

[p5200]

Absolutely, positively yes!

What ballman6711 said. If I've seen one, I've seen a hundred posts about how "deep" to seat primers. Seat them to the bottom of the pockets and they won't require second firing pin strikes to set them off.

These, wouldn't fire even with a second strike?

 

[.308 Norma]

These, wouldn't fire even with a second strike?

If they wouldn't fire with a second strike, you probably have problem(s) other than seating depth - firing pin problems, bad batch of primers? It's hard to say.
Regardless, if you don't seat the primers clear to the bottom of their pockets, part of the energy from the firing pin strike is going to be expended in driving the primers to the "bottoms of their pockets."

 

[Bfh_auto]

35 Whelen has a small shoulder. It's possible the brass is under sized.
I would bet primer issue. If not it could be brass.

 

[Walkalong]

Primers need to be seated until the anvil legs touch the bottom of the primer pocket (Minimum), and then a little more so the cup pushes down around the legs, up until it hits the bottom of the primer pocket (Maximum).

If seated to little (Anvil legs not touching the bottom of the primer pocket), the firing pin has to seat it fully and then have enough energy left over to crush the priming compound between the cup and the anvil. Sometimes it does not, these are the ones that so often fire on the second try. The first try seats them fully, the second try fires them.

bds has some great primer pics here somewhere that shows the cup and anvil and how they are positioned with each other prior to seating. The anvil legs are sticking out of the cup just a little bit.

After fully seating the anvil's legs and the primer cup is hard against the bottom of the pocket, it takes a great deal of pressure at this point to damage the primer so much it fails.

It is fairly easy to seat a primer too soft, not fully seating it, so that it misfires, but difficult to seat them so hard it damages them to the point of not firing. This statement is based on my decades of seating primers with various tools. I have never had one fail from being seated to hard/deep. Not saying that with some primer tools and some gorilla grips it can't be done, but it is 100/1000 times less likely to happen than seating one too shallow/soft.

We have threads here all the time when failures to fire end up being primers seated too softly/shallow. I can't remember one where it turned out someone managed to crush a primer into submission. I would suggest to all to try it. Some priming systems simply cannot do it for mechanical reasons. Some might have enough travel to do it if you have the strength, That cup surrounded by the brass primer pocket is tough to crush. Very tough.

I seat primers in my Dasher cases 5 to 6 thousandths below flush. Seat them to the bottom of the pocket.

 

[Rod47]

Be careful you're not setting case shoulders back excessively.

 

[Project355]

Be nice to see what the primers look like on the cartridges that wouldn't fire. I agree, could be the cases are just plain n simple too short.

If so.... there's a quick n dirty trick you can use. If the shoulders are set back too far, the effect is too much headspace, but that isn't really an issue IF and only IF you can hold the case against the bolt face. Normally an extractor will have a bit a slop, but only allow the case to move forward just a bit. In other words, a round held by the extractor claw can only move forward by what ever the amount of the "slop" is. The amount of that slop may be in excess of your firing pin protrusion+what it takes to set off a primer. Dunno what rifle you're using but... if you can find a way to get a bit of material between the extractor claw and forward part of the rim, you may be able to get ignition, and fire form the cases.

 

[NMexJim]

If they wouldn't fire with a second strike, you probably have problem(s) other than seating depth - firing pin problems, bad batch of primers? It's hard to say.
Regardless, if you don't seat the primers clear to the bottom of their pockets, part of the energy from the firing pin strike is going to be expended in driving the primers to the "bottoms of their pockets."

x1 on firing pin. Being high might eat up headspace depending on what type of action you're using. I will say that I like to seat primers using a hand tool like a Lee or similar. You can really feel "bottom" with them. Two, check twice to make sure you've got the right primer.