"Short Recoil" Vs. 1911 Locked Breech

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doctorj

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Can someone explain in simple English what the perceived advantage is supposed to be of Beretta's "short recoil, oscillating block" system as used in the 92FS, as opposed to the standard locked breech design of the 1911?

Thanks.
 
Well, in the first place, the "standard locked breech design of the 1911" IS operated by short recoil. Defined as recoil movement of the barrel of less than the length of the cartridge.

Beretta's oscillating block is just another approach to the same thing; developed by Walther for the P38 and its predecessors (HP) and successors (P5). It has the supposed advantage of straight-line movement instead of the tipping barrel of the Colt/Browning design. Both accomplish the same thing, locking the slide to the barrel until the bullet is gone and pressure drops off.

Berettas are functional and successful but have no emulators except the Taurus which is built pretty much to Beretta design. On the other hand, there are tipping barrel guns all over the place, hard to name a maker who does not produce one; Beretta (9000) and Walther (P88) included.
 
Guns that use the "Beretta" system: P-38/P1/P4, P5, Llama 82 (Spanish military sidearm), Z88 (S. African sidearm), Vector SP series, Taurus, French Service pistol, Beretta 951/Helwan and possibly the Korth thingy. The CZ-52 is similar, using rollers instead of a tilting block. Many machine guns use a recoil system relying on a seperate lock.

The P-38 system is not a controlled feeding system, like the Browning system is. This makes it a bit more feed reliable as the round doesn't have to fight the friction of breechface and extractor on the way in. The also, being straightline, extract easier (while still considered secondary extraction, Berettas will often extract without an extractor. No Browning gun would.)

The 92's feed reliability is well known and is the reason the gun is in use everywhere (not just as the M9). However, it's a bulky, more fragile and complex system.
 
Hey, I forgot about the Llama, and a friend of mine actually owns one... the M87 competition version. It is a smooth shooter and a much nicer made gun than their 1911 knockoffs.

Never saw a Vektor, but their pictures look a lot like Berettas and Llamas, depending on whether they have open or closed slides. The French Service Pistol IS a Beretta, the model 92 G with spring return on the decocker so you can't leave your dingus down.

I think it is a stretch to include a CZ52 in the "Beretta" action family as originally designed by Walther about 40 years earlier. Just as well count a Broomhandle Mauser because it has a separate locking block. Althouth I have read that ol' Fritz was looking at a C96 while working on the MP/AP/HP/P38. Now how did the author know that?
 
Thanks!

This is just what I wanted to know. I love being able to get answers to my firearm questions quickly! This is a great resource for those of us who don't have access to a good firearm library.
 
I mentioned the CZ-52 and MGs just to illustrate that the concept of using a seperate locking piece(s) is in fact very common and the only short recoil method used in long arms (the P-38 system being just one example).

The Browning tilting barrel, so common today, is useful only in pistols and is only superior in its simplicity, not function.
 
The Luger pistol is a true locked breech pistol. If you remove the extractor, you find that it does not begin to open until chamber pressure has dropped to zero. The case remains in the chamber, yet it can be removed with a flick of a fingernail.
The 1911 will extract (but not reliably eject) a case with the extractor removed. Obviously, residual pressure helps extract the fired case.
Can the 1911 pistol system, therefore, be classified as a delayed blowback like the Savage pistols with a rotating breech block?
 
I think you'll find that many gas operated rifles also have residual chamber pressure that aids in extraction. They are locked breech. The chamber pressure doesn't have to be zero. "Locked" means locked until pressure has dropped.
 
Do you mean "locked" only until the bullet has exited the barrel?
I have observed Garands firing in darkness, ejecting cases with flame coming from the case mouth. Gas operated rifles have a gas tube that is pressurized as a bullet travels past the gas orfice near the end of the bore, and that pressure may drop more slowly than chamber pressure after the bullet has exited. Therefore, it is not quite the same thing, is it?
 
No, I'm saying that you made up the definition of "locked" you are using.

Locked means that at the MOMENT of firing, the breech can not begin to open. In a automatic arm it will unlock at some point after that, the delay determined by the designer to lower chamber pressures sufficiently for safe extraction. Not (normally) zero pressure.

Torn caseheads are a result of residual chamber pressure (and dirt) in automatic rifles. There is chamber pressure, it may or may not help; but the gas tube is only so long, so the action opens before it is all gone.

Delayed blowback is not locked, the casing begins to extract itself immediately. This is slowed, but not stopped, even for a moment, at firing. Entirely different concept.

The Luger is probably one of the only self loaders that meets your narrow definition of locked.
 
Apoligia Pro Vita Mea. Actually, I was quoting W.H.B. Smith and R.K.Wilson, from their 1935 books, most of which I'd memorized by 1944. I'm not an engineer, so I don't make up definitions or take tunnel vision views of actions and mechanical motions. I do sometimes quote widely accepted definitions from the past that are all but forgotten today. My firearms library is reasonably extensive and goes back well into the black powder era.
Who originated YOUR definitions?
You can find an exception ot most narrow definitions: Many modern rifles work on a variation of David Williams' short stroke piston, a piston and tappet short stroke like the FN 49, copied in the MP-44, Kalishnikov AK-47, etc.. Contrary to most thoughtful definitions is the Soren Hansen Bang blow forward full power rifle action, where the barrel is free to move forward and the shooter's shoulder goes rearward in recoil (Note Julien's reaction to firing that in "Hatcher's Notebook".). The 1915 Savage pistol disconnects, after a delayed blowback initiation, by recoiling into and rebounding from, the muscles of the shooting hand. Etc., etc., etc.
I mostly know about older handguns. To quote Harold E. McFarland: "I have an abhorrance of sheet metal and wire spring actions."
My take (as a journalist) is that, after many, many interviews with some of this country's prominent firearms engineers, one notes that no two of them "speak the same language" when it comes to operating systems; perhaps some are trying to be more down-to-earth than others. My only excursion into mechanical engineering was with a book thereon in one hand as I designed several rather complex printing press systems. If you visit me, you can look over both the book and the last designed press. Printing was one of my earliest fascinations.
No offense meant to anyone; on this forum, you will see it all. My only reason for presenting alternate ideas is to evoke thought and comment, not to arouse the ire of scientists.
 
I'm not trying to offend your sensibilities or experience. But you did make the statement that a Luger is a "true" locked action because the pressure drops to zero. So I pointed out that it may be the ONLY locked breech repeater, if that is what you call locked. Almost all self loaders have residual gas pressure.

Here's a good mental test for a locked action:

Plug the barrel somewhere near the chamber and wax seal a cartridge case in the chamber, bolt (action) closed. Now pressurize the chamber. You will find that blowback, and delayed blowback actions can be opened by chamber pressure alone. But recoil (1911) and gas locked (M1) actions will burst before the bolt moves. Chamber pressure alone has no influence on the breechface. THAT, is locked.
 
Yes, if you raise the pressure to maximum gradually; plug the chamber with a proper size bullet, then suddenly raise chamber pressure to maximum (50,000 psi) through a quick dump valve and see what happens. You are comparing oranges and peaches.
The Luger pistol EXISTS, therefore, it DEFINES a completely locked breech; it is locked for most of its recoil cycle past the point where chamber pressure has dropped to zero. After pressure has dropped to zero, inertia opens the action and continues the cycle. Ergo, the opposite end of the spectrum is a partial, or momentary, locked breech. It is unlocked for most of its recoil cycle. The former cycles through recoil/inertia, while the latter locks only until the bullet has left the bore, so it does the greater part of its work through inertia and blowback. The breech is locked only until the bullet departs the barrel; considerable pressure remains.
My question was, where did you get your distinctions and/or definitions?
The 1911 pistol and many others are RECOIL operated. What is your definition of recoil? Where did you GET your definitions?
 
... observed Garands firing in darkness, ... flames coming from case mouth...

Heck, I've fired Colt Super 38 outdoors at Noon, with fully visible yellow fireballs at the muzzle and ejection port. :cool: :eek: :what:
 
I will say that the Luger is probably THE strongest auto pistol action. The only weakness would be the pins connecting the links but as designed they are harder than woodpecker lips.

The whole idea behind recoil v. blowback is the equal and opposite principle of Newton. The bullet moves, the opposing mass moves in the opposite direction, slower because it's heavier. That's the whole story of blowback. Recoil adds a locking feature between the bbl and breechblock/slide. The unlocking allows the heavier mass (breechblock) to accelerate and complete its stroke thru inertia. How you get the two parts to stay together and separate is the locking/unlocking. The length of the recoil stroke before unlocking is the time dwell. Usually they claim that chmaber pressure is zero but you can't prove by me. I ain't no engineer!
 
It doesn't matter how slow or quick you raise chamber pressure. If the action wears the common term "locked" the chamber pressure on the casing has no way of opening the action. That's the point I'm making, and you seem to be disagreeing with.

While terms like "recoil operated" have been used and abused long enough to have shifty definitions (especially when extracted from translated German manuals), "locked" is a simple dictionary term. All "locked" actions are unlocked through external forces. These may be tilting links, gas pressure on bolt carriers or manual manipulation. But if you remove any of these external forces, the action WILL REMAIN LOCKED.

Another fine example:
You can take the slide off a Glock, load the barrel and (with some striker tinkering) fire the round. The barrel and slide will remain closed and LOCKED to each other. There is no force or device to unlock them.

If you did the same with a Ruger MkII or Mauser HSc, the slide (or bolt) and barrel would go their seperate ways. They are not locked.


I think calling something "more locked" or "really locked" is about as useful "a little pregnant". An action is either locked or not. Is an M4 "less locked" than an M16 because the gas tube is shorter? No, it's just locked for less TIME. Not less locked.


As for the Luger, I could design a slow burning 9mm round that would have residual chamber pressure left at unlock. Would this suddenly change the Luger's status? Would it no longer be a "locked" action?
 
There are arguments about terminology, but there is no doubt the 1911 is a recoil operated, locked breech pistol. It is not blowback. In a blowback pistol, only the mass (technically not the weight) of the breechblock offers resistance to the gas pressure and keeps the breech from opening before pressure reaches a safe level.

The 1911 and the Luger (and all the other recoil operated pistols) are operated by recoil from the movement of the bullet. The barrel-slide combination begins to move backward as soon as the bullet begins to move, but due to the mass difference, the barrel-slide does not move as fast, so pressure will drop before full unlocking takes place. (Yes, I know about the drawings in Kuhnhausen's books showing the bullet leaving the barrel before the barrel moves. The drawing is wrong.)

If the bullet does not move, the gun does not open. If the barrel is blocked in such a way that the bullet cannot move, and the gun is fired, nothing will happen.

If this were done with a blowback pistol, the breech would open under high pressure and probably damage the gun.

Jim
 
Handy: Georg Luger performed the same experiment you described with the Glock slide/bbl with his early Luger for the US trials I think it was. They equiped a horse troop or regiment with 30 Lugers around the turn of the 20th Century. He fired off a round with the bbl and breechblock assemblies removed from the receiver. The breech stayed closed.

Jim Keenan: In my description of the workings of the autoloader would it have been more correct to say "the mass of the breechblock/slide is "massier" than the bullet?"
 
That's interesting that Georg did that, BigG. And it could be done with any weapon that has what is called a "locked" action.
 
If you have a bullet lodged in the beginning of the rifling just past the case mouth and you dump 50,000 psi into the chamber, the bullet will exit the barrel and the action will work normally. A gradual raise in pressure to (?). Therefore, using you scenario,
it will not accomplish the same effect in the same manner. The Luger pistol requires a rearward movement of the cannon (what the germans called the barrel and extension with breechblock and toggle system installed) to unlock, or break the straight line of the toggle system and initiate function. If you remove the cannon intact from the grip frame, press inward on the disconnect plunger, the cannon will fire a shot in the chamber and since there is nothing external to break the straight line, the case cannot extract.
I'm wondering why you refuse to tell us where you have gotten your nomenclature. It seems to me that if we could all access the same source, we would be able to discuss the mechanics of autoloaders in terms that everyone would understand. I don't see anything subversive there, but perhaps I have overlooked something.
Those who have said that the T-94 Nambu is dangerous because of the lateral sear should note the above. Even partially disassembled, the Luger will fire a shot; not so with the Nambu.
 
I'm sorry, I have no bibliography. There is no conspiracy: I didn't own copies of all the magazines, library books and web forums I've read in the last twenty years. As I mentioned, some terms do take a beating in the literature. The two worst ones are "double action" and "recoil". I have never found a book old enough to be said to coin either term, so we all do what we can and say what we mean.

Two terms which I have never seen defined or used in any other way (until you) are "blowback" and "locked" in terms of repeating actions. These terms are almost always used as opposites. Blowback seems to be defined as an action which is opened due to chamber pressure. A locked action is then one that can't be opened due to chamber pressure. (There are some, misunderstanding roller delayed blowback, that throw the word "lock" in, but they think the bolt actually pauses, which it does not.)

I don't think you understood either of my examples. The scenario when I spoke of a blocked or plugged barrel, I was speaking of a permanent plug, to demonstrate that "blowback" forces CAN NOT OPEN a "recoil" action (aka, chamber pressure). Same as Luger.

Also, you bring up the Luger's ability to remain locked if off the frame as if this was different from ANY other recoil pistol. It is not. Glock, 1911, CZ, BHP, Beretta will all remain locked unless they have a frame to UN-lock them. It's the same thing, and I already pointed this out.


YOU haven't answered my query about using slow burning powder in a Luger. Would this transform the pistol into an UN-locked gun or not?

Second question: Name any other self loading firearms that unlock at zero chamber pressure. Is the Luger the ONLY one?


If I am incorrect about what a locked action is, that is unfortunate, but I am in excellent company because I seem to be using the term in the same manner as everyone but you. If your heartburn is merely finding a standard definition, there aren't any. There are no textbooks or university gun nomenclature programs. I'll cough up standard definitions when you can define "manual transmission" or "cross trainer". The gun world is defined by its NON-academic shooters, writers and gunsmiths, not scientists. But it does help if everyone ATTEMPTS to use the terms in the same way.
 
1. Slow powder will cause a Luger to only partially open, and the pistol will not complete the retracting cycle. I was speaking of your scenario, where you pumped presure into a chamber behind a blocking loose bullet in the rifling, with no cartridge case to obturate the gas. (At least you neglected to mention chamber obturation and what kind of a barrel block you proposed.)
2. Name another? Borchardt. Sorry, it is an entirely different pistol.
3. My point is, these often abused definitions need to be reviewed and revised.
4. Recoil? Now, you are way, way over your head. This is a long story so fasten your seat belt.
General Julien Hatcher never attempted to define "recoil" in his books or NRA magazine articles. And, I know of no writer who did.
The usual (wrong) definition is "Newton's third law of motion: For every action there is an equal and opposite reaction." Well, the Germans and many others launched rockets using reaction engines, didn't they?
About ten years ago, I was giving a class and in attendence was an engineer who had done work for NASA, etc. I made a statement about recoil in handguns which he disputed. After he thought it over for a number of months, he discovered the following:
Every physics book printed in the English language contained an error of omission in Newton's third law! That proved the following:
Acadamia NEVER checks out a source (and) Everyone connected with acadamia copies everyone else's writing.
As you know, I'm sure, Isaac Newton wrote "Principia" in Latin, since he and other scientists of his day thought the much larger Latin vocabulary was better suited to scientific writing than English.
In 1930, a Physics professor from Southern California wrote a translation of Principia...BUT, he must have gone on a coffee break when he was translating Newton's third law of motion.
HE OMITTED AN ENTIRE PHRASE. THIS CHANGES EVERYTHING UNEXPLAINABLE BY REFERING TO REACTION BETWEEN 1930 AND ABOUT FIVE YEARS AGO.. Everybody in the scientific community in the English speaking countries quoted the incorrect translation.
The enginer's name was D.Y. Kadoshima. The book he wrote was titled "Handgun Recoil or the Fundamentals of Motion."
Incidentally, he apologized to me therein for doubting what I'd said. I was absolutely correct in the "what"; he supplied the "why..."
So, if you look at a college or high school physics book from 20 years ago and compare Newton's third law of motion with a textbook published last year, you will determine that Newton knew what he was talking about, and acadamioa was mumbling along with the tune for over 65 years.
Mr. Kadoshima also published a paper on "Diurnal Tides" that has been the subject of lots of mumbling along with a frayed tune since Hector was a pup.
Since acadamia and the textbook publishers refuse to admit such gross disservice to the scientific community, I don't know where you can obtain a copy of the book on recoil. You can find his paper on diurnal tides (that was originally part of the book on recoil) on the internet (from Australia) by writing D.Y. Kadoshima into the Google search engine.
The entire scientific community became upset with him, but without admitting gult, quietly undertook changing the error from 1930.
Despite the obviously flippant remarks of some gun writers concerning what recoil in a handgun consists of, it is an enormously complex subject, since individual perceptions and physiology enter the equasion.
And, if you think it is a simple thing, lean against a wall, resting your entire leaning weight on one palm. Well, there's obviously the action, but where is the "equal and opposite reaction?" read the missing phrase in translations of Newton's third law of motion and you'll be amazed and the question will be answered with scientific exactitude.
Now, that's enough bantering on this kind of thing. Back to the real world.
 
Wow, thank you for completely evading every question and comment. I don't think you've read and comprehended much I've written, so this is really no longer a debate.

I'm not sure what all the biographical data was for, or what you wanted to hear from me. And I'm no longer sure what you were taking issue with. I had thought we were discussing how firearms work, but I see I was mistaken.

Despite Newton, textbook makers, engineers you met once, Borchardt and chamber obturations, I think I'll stick with calling 1911s and M1 Garands "locked breech".


That was what we were discussing, right???:confused:
 
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