Semi autos' slides lock back when empty - How's this work?

[surprise_i'm_armed]

After a semi auto pistol's last round has been shot,
the slide locks back.

Can someone explain the mechanical process that goes
on to accomplish this?

Also: Are ALL semi autos supposed to do this on the last shot?

Some forum members have complained that their slides do not
lock back after the last shot. Is this a failure, or are some semi
auto's just not designed to lock the slide back when the ammo's done?

Thanks in advance.

SIA

[Target1911]

Most all modern semi auto lock back.
After the last shot is fired and the slide comes back, the magazine follower pushes up on the slide lock therefore locking the slide back.
If you insert an empty mag and pull the slide back you can watch and see how this works.

[Beiruty]

SIA,
On my P30 if you grip the pistol high and in on way pr another, you bump the long slide release while the slide is recoiling, the pistol will not lock the slide back. It might not be a design problem, simply a user error, readjusting your grip will solve the problem.

[Travis]

I wondered the same thing awhile back, if you take your slide off you can see how the magazine spring keeps the
slide release bar up to keep the slide back. If you have a round in the magazine when you put it in with the slide off you can see how the spring stays compressed and doesn't push on the slide release. Atleast that's the case on a glock

[LaserTex]

My Ruger LCP is not designed to lock the slide back after the final round but has a manual slide lock for use on the line (cleared weapon indications). My Ruger P90 .45 does automatically lock back (as was said - like most modern firearms). Depends on the gun.

Doug

[USA1]

On a Bersa Thunder, The slide locks back after the last round is fired. But unlike most guns, when you insert a new loaded magazine, the slide will automatically release and chamber the new round. That took some getting used to.

[chabouk]

The only current modern pistol without automatic slide lock that I know about is the P3AT. The P32 has it, but the .380 doesn't.

[Dutch]

if you take an empty magazine and insert it into the gun while watching the slide release lever you might be able to see it move depending on your gun. I can see it on mine.

[marksiwel]

The REAL reason

Magic

[gigag04]

On a Bersa Thunder, The slide locks back after the last round is fired. But unlike most guns, when you insert a new loaded magazine, the slide will automatically release and chamber the new round. That took some getting used to.

On many USP's and some other pistols if you slam the mag in, the slide will drop. Feature IMO.

[jimlongley]

I have a couple that do not lock open after the last round, designed that way.

[srothstein]

My North American Arms Guardian 380 does not have a slide lock back on it. No way to keep the slide locked back at all, ever.

In my experience, some of the modern pocket pistols do not lock the slides back, but almost all full size pistols do. As the design gets older, there is more of a chance to not see the slide lock back.

[Embalmo]

In Hollywodd, not only will the slide lock back, the hammer will somehow cock itself over and over again so the gun will make a click, click, click sound.

[Embalmo]

On a Bersa Thunder, The slide locks back after the last round is fired. But unlike most guns, when you insert a new loaded magazine, the slide will automatically release and chamber the new round. That took some getting used to.

Mine don't (Ultracompact 9 and Duotone .380)-Which BT have you got? I'm not an expert, but that sounds like it might be a malfunction. Sometimes a worn, or itty bity slide lock will disengage from the jarring of the next inserted magazine. My LCP has such a tiny slide lock that if you push a magazine in it with any force, it will release and chamber the first round in the magazine.

I'm not an expert, so for all I know there are other models (Bersa has a lot) besides the ones I've got that have that characteristic.

Embalmo

[USA1]

On a Bersa Thunder, The slide locks back after the last round is fired. But unlike most guns, when you insert a new loaded magazine, the slide will automatically release and chamber the new round. That took some getting used to.

Mine don't (Ultracompact 9 and Duotone .380)-Which BT have you got?

It's the Thunder.380.

Ok, I just checked and it appears that the slide is being released because I tend to slam the new mag in.
I always thought this was some neat feature.

I've had this same result with a new Bersa and a recently purchased used one...oh well.