Bumping this thread because this exact thing happened between a police officer and a suspect here a few days ago. Officer stopped suspect in the street, asked for ID and the suspect pulled a .45. The two struggled for the gun and the officer grabbed the slide and was unable to stop the gun from cycling as the suspect emptied it. The good news is that the officer was not hit and took the suspect down without drawing his own weapon. I’ll see if I can find a link.
"The officer then clutched Spells’ right wrist with one hand and grabbed the gun with the other hand. The officer tried to grip the slide on the semiautomatic gun, hoping to jam or disable it. But Spells kept firing the weapon until it was empty. This gave the officer minor cuts on his hand.
Once all the bullets were spent, the officer was able to take Spells into custody before backup arrived.
The first two rounds Spells fired hit a passing car, and at least one other shot struck a nearby home. No injuries were reported."
Interesting. Do you have a cite for this?
I don’t know if it is the same model of pistol that Ranger Jeff is referring to, but I have personally witnessed the firing of a suppressed .22 LR caliber pistol similar to that described. The pistol is based on a Beretta Bobcat, modified with an intergally silenced barrel and a crossbar lock on the slide in place of the thumb safety. I was told that this is the same configuration used by the Mossad for “covert use” (e.g. walking up behind some sucker and putting one behind the ear). The sound is as advetised; you can hear the sear release and firing pin impact distinct from the much reduced sound of the muzzle blast (with a subsonic round) which sounds like an assertive cough. I’ve also seen a suppressed Ruger Mk II (allegedly in use by US Special Forces now that the Hi Standard pistols previously used are well beyond design lifetime) which had a muzzle blast that was no louder than blowing through a comb.
Stranger
Don’t know about the Beretta; I’ve seen a couple of attempts at a flip-down catch on the Ruger Mk II and III that prevents the “slide” such as it is from moving.
I simply use my thumb. I don’t know about blowing through a comb - that sounds like something you picked up in the Philippines or Amsterdam - but CB shorts or Colibri 20grn rounds are decidedly not attention-getting.
I’ll go make a quick video if I can…
Would it be conceivable that Spells did the exact opposite of what Gbro described in his post?
In other words, a 1911 with a .45 Auto spring, loaded with .45 Super ammunition?
If not that, then maybe he wasn’t able to get a sufficiently good grip on the weapon to prevent the slide from operating.
Just curious.
What do you think, Gbro? 
At least in the case of a Glock 19, using one’s hand to prevent the slide from reciprocating does not require any great strength and does not cause injury.
In an attempt to answer JBD…
1st of all i do not know everything about firearms, TBS, the link was very interesting and I wasn’t there nor do i have all the facts.
The fact that the officer received minor cuts on his hand makes me think a couple things. one he certainly did try and disable the simi auto and like i posted, the practice of trying to move the slide out of battery like was taught in the past can be hard to impossible at best because of design changes from the Mil Spec 1911’s. Was the officers initial intention to try and prevent even one round from being fired, or to try and jam it on its cycling???
Also if the slide isn’t tightly squeezed and then control lost because of what one would feel happening to that hand might lead to releasing the grip.
To disable the firearm the slide needs to be gripped tightly and held and dam any injury that could be caused by the slide. That has to be a solid mindset before preforming this.
Now as to the ammo,
The link certainly doesn’t elaborate but i used .45 Super as an example because i have one. However, .45 ACP +P is a reasonable possibility. And the size of the gun is also an issue. The smaller the gun the leads to a shorter slide cycle and that requires a much stout-er recoil spring making it harder to dis-able the gun.
From experience, I have seen simi-auto’s fail to cycle with poor hand position where the support hands thumb is held tight against the slide causing failure to extract.
The officer in the link was very fortunate. 
I’m not a gunsmith, but the equal and opposite reaction doesn’t happen unless you are talking about a .22LR automatic pistol. Higher calibers have something (and I don’t know the term for them) that braces the slide from blowing straight back because it would simply destroy the hell out of the gun if it came back with the force of the bullet.
So, if you tried holding the slide, you would be assisted by this device. But, take a Ruger Mark I in .22LR. The slide comes back with the force expelled because it isn’t restrained in any way because of the lower force.
I think. 
When we were taught gun disarms in self-defense class, we heard the same sort of thing as the police - try to lock the slide and prevent the gun from cycling. (Or hold down the hammer on a revolver.) This is secondary to “getting the fuck out of the way of the bullet”, and I never had to use it, but every little bit helps when you are trying not to get shot.
I have heard people advocate trying to push the safety on in a gun disarm, but I am not anything like familiar enough with the various models to know where to begin to look, especially in a situation where the damn thing is going off in my direction.
Gun disarms are a low-percentage move anyway.
Regards,
Shodan
Well, this isn’t quite right. All (I think) .22s, many .380s, and one or two* 9mm pistols use a blowback mechanism. In a blowback gun, the breech is “locked” only by the inertia of a bolt or slide, and the friction of the case walls against the chamber. The slide or bolt is blown back by the case head. Only the inertia of the bolt or slide prevents the case from rupturing. It is a little fussy, but is simple and cheap for low powered rounds.
The alternative, used by most center-fire pistols is a locked breech. The slide or bolt is mechanically locked to the barrel when the gun fires.
However, in the most common designs (recoil operated) the slide and barrel ARE free (well, they do act against a spring) to move rearward in the frame. This motion eventually unlocks the barrel from the slide. The barrel then stops, and the slide continues rearward, ejecting the spent case, usually cocking the action, then reversing to strip a round from the magazine, chamber it and finally return to battery (locked and ready to fire again)
The gas operated desert eagle is the only large bore pistol (excepting those that are based on rifle designs) that you might encounter that is not recoil operated.
*SMG based 9mm designs (Uzi, MAC-10,11) tend to be blowback. I think there is a really cheap “normal” looking blowback 9mm pistol…HiPoint maybe? Heavy.
Holding down the hammer on a revolver will work but I don’t know about the rest. To lock the slide, you have to be pushing up on the slide lock as it fires, and the bad guy can easily flip it to release the slide too.
Some don’t have external safeties that you can fiddle with.
Okay, as for that request for a citation, um, there are some things that just are very rarely documented. I’ll say that given an experienced Special Forces Armorer Sergeant or two with their professional curiosity challenged, a proper machine shop, necessary materials, and a firearm to be modified, you’d mostly likely end up with a, um, modified firearm. I can state from personal experience that if a non-SF grunt type (dismounted Cavalry, for example) is on friendly terms with the members of an A-team and is overheard in a general drinking/griping session that he wished his M-16A1 had a peep sight with a smaller aperture, a SF Armorer Sergeant probably already has a modified sight in his tool/parts kit and can have it changed out in less than 5 minutes.
I’ve heard the report of a .22 lr from a suppressed Hi-Standard (that’s what they had back then, maybe the Rugers were just coming in), fired indoors, is like “Hold a big hardbound book, like a dictionary, at shoulder height and let it fall onto a carpeted floor.”