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Firing Out of Battery

14849 Views 53 Replies 22 Participants Last post by  Visceral_Malice
Well, it took me a while, but I finally did join 'that other site'. I don't post but I do sort of lurk around and read.
I don't know if any of ya'll are members over there or not, but there is a member there who posted a thread about a 5.7 that blew up in his hand because it fired out of battery! I pulled the magazine from mine and inserted an empty and tested my own personal weapon. It fired a full 1/4 inch out of battery!
I'm sorry ya'll but that scares me. I'm using this as a duty weapon and now I find this out? I never would have thought it unless I tested it.
He went on about how FN never really got back to him and he feels like they just wished he would go away, or else they just forgot about him. I can't imagine I would forget a customer whose gun blew up in their hand!
He did say that he was shooting reloads, and normally I would have jumped all over that as I know a lot of reloaders who tend to 'hotload'. But firing out of battery has nothing to do with the load charge. That's purely mechanical, and in this case, poor design.
Just kowing that mine COULD fire a full 1/4 inch out of battery has me to the point that I'm switching holsters today and putting my Glock back into service.
I can't believe that I bought a $900 'target pistol'. :cry:
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Like MadDogDan stated: it is a mechanical impossibility to fire out-of-battery unless something else went wrong.

Take a look at the firing pin block on the underside of the 5-7's slide. See how it is angled? Hold the slide over the frame, and pull the trigger (thumb the hammer up first so you don't beat the frame). Note the little knobby thing on the right side of the hammer. The sole purpose of that lever is to unlock the firing pin as the trigger is pulled. It cannot do that until the slide is all the way forward. It will not allow the falling hammer to touch off the primer until everything is seated.

Now, with the slide off the frame, position the slide 1/4" to the rear. See anything? The lever that manipulates the firing pin block can't even touch the firing pin block that far out-of-battery. About 1/8" to the rear does the lever even touch the block, but again: the angled cut of the block means the firing pin stays put until the slide is closed.

Now reattach the slide. Pull it so it is 1/8" back. Check the barrel and slide. Notice anything now? Let the slide forward and pull it back 1/8" a few times. Check the barrel block through the ejection port. The barrel is fully seated against the breech face. The barrel is in battery from the 1/8" point forward, so even if the firing pin was released early, it wouldn't cause a catastrophic failure.

I'll say it again: mechanical impossibility.

The design prevents the firing pin from being unlocked until the weapon is in battery. Even if the hammer drops, it can't fire the pistol until all is locked up.

The kind of damage on that pistol can also be caused by an over-pressured round. Pressures too high can force the chamber open before the bullet passes and result in a case failure.
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I placed little circles of scotch tape over my spent brass to smooth the surface out and make it easy to see contact.

At 1/4" out, click of hammer fall, no mark on the primer.
At 1/8" out, hammer fell, no mark.
Here's the kicker: The weapon was out of battery only slightly because the once-fired brass was slightly oversized and the chamber would not close completely. I measured about 1/32" out. Hammer fell, NO MARK ON THE PRIMER. I pounded the slide closed a second time, and got it close enough to where the firing pin finally made contact.

I am completely convinced this is a non-issue; that unless something else went wrong with the KB'ed pistol, there is no way it fired out-of-battery. I'm wholly convinced the failure came from the reloads and not the pistol.

Important note for using primed brass: The hammer is going to try and force the slide closed when it falls- don't let it. Drop the hammer, then extract the round. Check it for marks, don't rely on the primer firing alone. Wear ears and eyes, those little primers are loud. Keep the muzzle pointed in a safe direction as if the pistol was loaded with live ammo. If the rounds have not been resized, they will not fit in the chamber all the way.

You'll see this out-of-battery theory is utter nonsense.
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Check Here for a response from a guy who works for FN.
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