Firing out of battery

[brian45acp]

I learned that much of the issues with cz needing a short OAL isn't always the reason it won't go into battery. In my case it turns out some brass I get is out of spec and too long by about 3-5 thousandths beyond SAMI. This causes the brass to hang up the slide from going in battery because it head spaces then that's it. 

Today at the match I had another one and the hammer still dropped. It got me thinking so I checked the gun which is a sp-01 that is stock except for my slide was milled for an optic. That does expose the FPB but I don't suspect that changes anything. The hammer will still fall with the slide pulled back quite a bit. On the other hand at the point the barrel disengages from the lugs then the trigger is dead and hammer won't fall.

I checked with a snap cap and a piece of masking tape over the primer area to check at what point out of battery the firing pin would still make contact. It will punch the primer with the slide slightly pulled back but not when pulled back more to the point the barrel isn't engaged. Basically I think that point is when the FPB stops the firing pin but when just a little out of battery the FPB disengages and the primer will get hit. 

I've always thought a gun that fires out of battery is a bad thing but looking at the cz the barrel stays engaged for quite a while which makes me think it's part of the design and not really an issue. A glock or 1911 pretty much immediately unlock the barrel as the slide moves and then the trigger won't function at that point. The cz is very different I noticed and the barrel stays locked and allows quite a bit of slide movement 

Do you guys have any thoughts? 

[IDescribe]

Almost all semi-automatic pistols will fire a hair out of battery. It's the way it is.      
 

[ChuckS]

It is just a matter of the tolerance in the trigger bar engagement with the notches in the slide. There has to be some slop depending on manufacturing tolerances and reliability when other than perfectly clean. These pictures were stolen from the following thread:

 

Edited October 30, 2016 by ChuckS

[brian45acp]

Ok sounds good. Once my OCD kicks in I seem to make issues out of stuff that isn't an issue, lol. If the gun fired slightly out of battery it doesn't seem like the barrel disengages much later and at that point the trigger doesn't function which I'm sure is by design. 

I get brass so cheap it's worth the ocassional bad round. The darn brass bottoms out and slide won't close because the brass is too long. I don't want to ream my barrels for crappy brass that is the cause. 

Edited October 31, 2016 by brian45acp

[IHAVEGAS]

The whole 'needs short oal' thing is a mystery to me. I've got 4 and the only problems I have had were due to short bullets. Now I feed them all 147's at 1.15 but they have all seen several sizes and shapes of bullets and never shown a preference for a short load.

First time I noticed my 1911 would fire out of battery it bothered me too.