automatically chambering the first round?

Not open for further replies.

piece of meat

Jun 29, 2010
was wondering if this is normal or is a sign of a defect of some kind that is wearing down my slide stop mechanism:

whenever i slap a loaded (factory) mag into my cz, i dont have to do the whole slide release thing; it just loads the first round automatically if i slap the loaded mag into it.

never seen another gun do this normal and therefore just an awesome feature of this gun, or could it be some kind of defect?
i have never heard of any pistol that automatically chambers a round when a mag is inserted.

maybe give the CZ customer service center a call and see what they think about it.
Um, what gun, a 24, 27, 35, 52, 75....
lots of CZ's out there

Um, it can, kind of, check the mag, see if other loaded mags do it too, see if the slide drops if you seat the mag softly.

what happens is you slam the mag home and bump the slide/ slide release and it goes forward and chambers the round, it could be worn parts, weak springs, a really stiff new mag spring pushing the ammo just a bit high. If it doesn't bug you, find out why and decide if you want to fix it or not. BTW it can happen on almost any auto.
Last edited:
My (nearly new) CZ-75B Omega does this on occasion if I really smack the magazine home.

I was advised that this is normal for most all autoloaders.
Please DO NOT seat the mag genitally! (lol...sorry couldn't resist that one) This actually does happen quite frequently with many makes of guns. Not normal, but does happen. Might be as simple as the angle your holding the gun while you do it. Make sure you keep that puppy pointed downrange.
Yes, many guns will do this if you slam the magazine in hard, because the impact bumps the slide enough to release the catch. My Baby Eagle and a friend's Glock both did this even when new. Like someone else said, try inserting the mag "gently" :D and see if it still happens.
Very funny guys. My wife is now asking me what the heck I was trying to do, I told her I was seating the mag genitally.

Realize, that the follower of the empty mag is what holds the slide open. When you drop the empty mag, pressure from the slide on the stop is what holds it open. If you jolt, jiggle, or bump that slide, and cause it to stop pressing on the slide stop, it will fall, and nothing will stop the slide from moving forward. Any pistol can do it every once in a while, but it it started to do it regularly, I would want to make sure that the slide stop isn't dirty or damaged.
I have never experienced that in an autoloader. Sounds like a cool "feature" though.

Seems like a guy could come up with a way that the gun would be designed to do this however...
softly, better NOW??
sorry for clicking the wrong one for spell check

LOL, yeah I wouldn't suggest it
Last edited:
9mmepiphany, Gord was advised by someone that "this is normal for most all autoloaders." You question if I have facts or knowledge to be more persuasive as to my credibility, well none of my autoloaders i.e. Berettas, Stoegers, Rugers, CZs or Nighthawk have every done it. I didn't say it couldn't happen, I just said it wasn't normal. Not particularly looking for approval on credibility, just stating from my personal experience.
Has happened a few times on my G17 when inserting the magazine with force when adrenaline is pumping during training exercises during training. My co worker's G23 does the same thing but almost every magazine. I still tap rack just to make sure it loaded a round. I will never go by chance and guess that it loaded one in the chamber. I have seen it happen many times. Not to big of a deal.
I don't think I've ever had a polymer handgun that wouldn't do it is you seated a full mag with authority...just slam that mag into the magwell...although I can't say the H&K VP-70 did it much.

The first pistol I ever experienced it with was a 1911, followed by a Sig 226 and a Beretta 92...I figured they were just trying to catchup with the H&K P-7 for the quick release upon insertion of the mag. The P7 releases a locked back slide when you depress the cocking lever.

A little investigation lead to an understanding that it was caused by vertical play between the frame and slide. The inertial of the the full mag being inserted forcefully lifted the slide upward enough to allow the slide stop to be pressed downward by spring pressure.

Normal would depend on the choice of weapons being referred to, not uncommon might be a better description, but defective or abnormal would not be correct
I daresay ANY handgun can do this if the mag is jammed in hard enough, vertical play or no. The reason for this has already been explained in post #10.
was wondering if this is normal or is a sign of a defect of some kind that is wearing down my slide stop mechanism:

whenever i slap a loaded (factory) mag into my cz, i dont have to do the whole slide release thing; it just loads the first round automatically if i slap the loaded mag into it.

never seen another gun do this normal and therefore just an awesome feature of this gun, or could it be some kind of defect?
I have seen Heckler & Koch Model 4 do that. That is pretty cool if you ask me. My ole' CZ75 from the 1970s didn't do that.
its a 75b omega. it doesnt do this occasionally, it does it every single time if i slam a factory mag in. thing is, the slide has NEVER failed to lock open on an empty mag, and remains firmly locked until i push the slide release (or slam a new mag in) so it doesnt seem to be a case of a weak/loose slide lock.

it is pretty cool tbh...i used it today to qualify for my CHL and every other gun on the line had to put their mag in then manipulate the slide to chamber a round; mine just automatically was ready to fire the instant i put a new mag in.
I can get all my autos to do it if I move the gun toward the magazine with enough force or slide the magazine into the well and then smack it home. The force of pushing the gun toward the magazine transfers to the slide release and causes this to happen.

It will probably happen easier if the slide release is dirty. It does happen easier on my Sig P229, but that's also a 15 year old gun with original springs. It's much harder to do on my G27 or P226 Elite, but both of those are new within the past 4 months.

Does it happen easier when the slide is held open on it's own, or when you manually hold it open? If it does it when the slide holds on it's own, it could be an indication that the magazine spring isn't strong enough. The slide stop needs magazine spring pressure to hold it open initially until the recoil spring is has enough pressure on the slide. If it happens equally whether held open by magazine or manually, it could be a weak recoil spring. A weak recoil spring will put less pressure on the slide returning to battery, which in turn puts less pressure on the slide release, which makes the slide release easier to push down.

All in all, you're probably not dealing with a serious mechanical problem. As long as the gun remains reliable, this could just be 'one of those things' that gives it a little character.

If you really can't handle it, I would suggest replacing the magazine spring or recoil spring, or both depending on other symptoms, and making sure the notch in the slide is clean with crisp angles.
My Bersa Thunder 9 UC does this on occasion. It was startling at first, thought maybe it was broken. Took it home, did a full teardown and checked it out. Nothing wrong with it. Function checks flawlessly. I still find it slightly unsettling when I'm not expecting it, simply because none of my other pistols do it. As long as it doesn't slam fire, I'm happy. The finger off the trigger rule certainly applies.
It is common. I had a Springfield 1911 that would do this and I have seen a Sig 220 that did it also. Both were completely reliable.
I've never noticed it on my personal CZ (a PCR), but I've had several guns that would do this (e.g., S&W 5904, Kahr E9). There is less slide stop engagement when you remove the empty magazine and insert a new (loaded) one with any amount of force, causing the slide to run forward when loading. Since I intended to chamber the round anyway it is not serious cause for concern, but I would rather have more control over the process. Check your slide stop and slide notch for unusual wear (rounding off), but don't spend a lot of time on it as long as the slide reliably locks back on the empty mag as it is supposed to.
Last edited:
I think its simply a transfer of energy. If slapped home hard enough, I think any slide could drop. The CZ may do it more often because of the lowerer than average slide mass, they just don't have big heavy slides.
My CZ52 does it, but it isn't a feature, it is a sign of a ancient magazine spring and a so-so fit of the slide cutout and slide latch to each other.
It also does it when I remove the empty mag sometimes! surprise!

My P22 will do it when it is dirty, you have to slam the mag in hard enough to pop the top round out to get a clean P22 to do that trick, often causing a mis-feed (round's nose goes WAY too high)

My Walther PPS won't, my Ruger mkIIIs won't, my 1911 won't and MrsBFD's XD won't ... in fact, none of those guns will do it, even if I try to get them to do so. The ZTokarev won't, but that's because the lanyard loop on the magazine would hurt! It might be physically capable of performing this "feat", I don't know.

I don't know if I could get a mag inserted that forcefully into mouseguns I have around, most of them are in the "slam the mag home as hard as I can with the tip of my left thumb stuck into my right fist" category due to short grip.

So I have two guns that do it, and a big pile that don't. The two that do it fit into the "not quite a malfunction" category, not the "feature" category ... as far as I can tell. Get used to it, find out why it happens at least to determine if it is a precursor to real malfunctions, and never, ever, under any circumstance should you count on it working, do a quick chamber check when it happens to make it a habit, because if the feed boss doesn't pick up the top round you have a surprise unloaded gun in your hand.
Not open for further replies.