View Full Version : So...what's going on here?

chris in va
August 3, 2009, 10:45 PM
Federal 7 1/2 shell, good firing pin dimple.
http://img526.imageshack.us/img526/9928/imgp4820.jpg (http://img526.imageshack.us/i/imgp4820.jpg/)

Remington 7 1/2 'sport load' shell, shallow dimple with 1 out of 5 needing a restrike.
http://img36.imageshack.us/img36/3848/imgp4821.jpg (http://img36.imageshack.us/i/imgp4821.jpg/)

Both primers appear to be seated at the right depth, both shot from the same Mossberg 500. All the Federals shot that day worked fine.

August 3, 2009, 11:45 PM
Very interesting.

The primer in the first picture looks a little cratered.

Cratered primers and light strikes could indicate a weak mainspring.

How old was the ammo and how was it stored?

August 3, 2009, 11:57 PM
I can't be sure from your pics, but the Federal hull and the primer look bulged! Are you following the recipes for all components, or using them as a general guideline? I know there is a primer availability problem; but, if you start indiscriminately swapping components, especially primes, you may get into over pressure problems.

I've been reloading shotshells over 40 years, and I've learned that I can minimize my troubles if the hull and primer are from the same manufacturer.

chris in va
August 4, 2009, 12:15 AM
Both are factory, store-bought shells, about 2-3 years old max. My ammo gets stored in a black non-sealed ammo box in the closet in VA and (now) KY.

All the Remingtons looked like that. Do they come with harder primers than usual?

August 4, 2009, 12:56 AM
Per Z13, when I first saw your pictures I concluded that you had seated your primers to deep. I then read that these were new hulls. I pulled a number of ounce fired hulls and new Remington shells out and not one of my hulls matched your type of primer. My active hull collection goes back to the old Blue Peters. (Hard to believe that anyone still has ounce fired BPs). The primer in the Rem hull resembles a Cheddite primer. Quite curoius.

August 4, 2009, 01:58 AM
olddrum1: I agree that primer looks exactly like a cheddite 209. I have a box sitting in front of me for comparison and they look identical.And it does appear to be seated rather deep,especially compared to the federal.hmmmm

August 4, 2009, 10:26 AM
Didn't realize they're new shells: Back to square one... As kozak6 mentioned, insufficient firing pin travel could be caused by a weak spring. A short (worn) pin, excessive head space, or, most likely, crud on the pin could be the culprit. Also, a tight/rough/dirty chamber might favor one brand of shells over another. Just because ammo is manufactured to industry standards, doesn't mean there isn't a little variation in the dimensions. There are comments in the archives in the nature of: My old band-W shotgun never did like brand-R shells.

.45 COLT
August 4, 2009, 09:39 PM
I looked at a fired Federal - the hull with the rolled paper basewad - and a fired Remington - the game load. black hull. The primers look about like the ones in the picture, the Fereral with a deep strike, the Remington shallow. In unfired examples, the primers are seated to the same depth - flush.

The fired Federal primer had backed out a bit, the Remington didn't. I'm guessing the Federal had the Federal 209A primer, very hot. Saves a bit on powder.

Then I measured the rims. The Remington measured .062" where the radius from hull to rim starts. Good, sharp radius. The Federal measures .075", with a large radius. Then I measured a Winchester AA CF shell, .064". The Federal rim is holding the shell farther back in the chamber, thus a deeper strike. Hold your two shells rim to rim and look at them. The difference is very evident.

I can't find my dimensional drawings right now to see what the spec is, see what's "right" and what isn't.


chris in va
August 5, 2009, 10:33 AM
I can't really tell to be honest, both look like the shoulder starts at the same point. The Rem does have a more rounded rim profile though if that makes any difference.

Just for the heck of it I rechambered a fired Rem shell and the pin put a very deep crater in the primer. Weird.

Dave McC
August 5, 2009, 07:56 PM
Primers vary slightly in hardness as well as Brisance.

To save wear and tear on Google, Brisance is the "Hotness" of the primer's spark.

As long as ignition is 100%, not to worry.

chris in va
August 5, 2009, 10:50 PM
As long as ignition is 100%, not to worry.

But that's the problem, it wasn't setting off the primer 1/4 of the time.

August 5, 2009, 11:11 PM
First thing I'd do is try both varieties of shells in a different shotgun. That should indicate whether it's the ammo or the gun.