What causes hang-fires?

[montana_native]

I had one this morning out of a Remington 700 243 AI. Just a fraction of a second delay, but enough to make me a bit paranoid for the next few shots. That shot was about 80 fps slower than the others in the group. CCI 200 primers and H414 powder witha 105 A-max was the load.

Thanks.

[boomtube]

We can't reall KNOW can we? The cause and results do get blown down the bore, eventually.

Been guessed that tumbling media clogs some flash holes. The explosive pellet may have been crushed during seating. Or, the primer may not be pushed fully home so the pin impact is cushioned enough to retard full detonation. Or a tiny bit of the compound may be contaminated by finger oils. Or the firing pin impact may be soft due to a weak spring or crud in the bolt. Or powder demons may be at work!

[montana_native]

If I had to guess at one of those causes you listed, it would be the primer not seated all the way. It's Lapua brass and the primer pockets are very tight.

Thanks

[James H]

H414 can be dificult to light in cold temps.
I would switch to H4350 powder or CCI 250 primers.
Either should solve the problem.
James

[J E Custom]

Originally Posted by montana_native

I had one this morning out of a Remington 700 243 AI. Just a fraction of a second delay, but enough to make me a bit paranoid for the next few shots. That shot was about 80 fps slower than the others in the group. CCI 200 primers and H414 powder witha 105 A-max was the load.

Thanks.

That much change in velocity would indicate to me that you had a bad primer.

Some times if you handel the primer with your hand it will get contaminated with skin oils
and doesn't ignite properly causing a delayed ignition and a slow flame propagation.

The other thing that happens in colder weather is that the fireing pin and spring have
to much grease on them and it will slow or stop the firing pin from striking the primer.
but this will not change the velocity like in your case but will cause hang fires.

There are a lot of other possibilities like under sized cases, poor primer fit,weak fireing
pin spring and/or a short firing pin and deep seated primer combo.

J E CUSTOM

[Mikecr]

Load a fired round and pull the trigger while watching the bolt. If that handle has any rotational movement(slight twitch up or down), then energy is spent doing so.
Just a quick check

[Doug in Alaska]

Originally Posted by J E Custom

That much change in velocity would indicate to me that you had a bad primer.

Some times if you handel the primer with your hand it will get contaminated with skin oils
and doesn't ignite properly causing a delayed ignition and a slow flame propagation.


J E CUSTOM

Wow, I've been reloading for well over 40 years and have always handled my primers. I've never had a hang-fire but you bring up a very good point I had never thought of. How do you suggest getting the primer into the primer seating cup on a RCBS machine without handling it, rubber gloves perhaps?

Thanks,
Doug