only 3 gun action types? change my mind...

S

Shadow9mm

New member
I was having a discussion in another thread that made me do some thinking.

I think there are only 3 primary types of actions.

Manual, bolt, lever, single shot, falling block, muzzle loaders, revolvers, etc.

Recoil, where the energy of the cartridge pushing back, creating recoil, cycles the action. All are generally delayed, such are roller, or locked breach. Straight blowback uses the mass of the slide or bolt to delay the action and is therefore a recoil operated system.

Gas, which is not directly effected by the blowback/recoil of the cartridge but has its action controlled by the gasses in the barrel to unlock and cycle the action.

I will grant people have put all kinds of special names on things and tried to be very specific within the sub catagories, but everything falls under one of these 3.

change my mind.
 
Last edited:
You are not following the accepted definitions that have been industry wide standards since the 1890s.

And, you're being inconsistent, as well.

You separate gas and recoil systems but lump together blow back and recoil operated. This is incorrect.

If you want to reduce it its most basic level, ALL semi and full auto systems are gas operated. Without powder gas, nothing happens.

But, we don't do that. We define the different system by their method of using the gas pressure of a fired cartridge.

A Blowback system is one where the bolt/breechblock/slide is not MECHANICALLY locked to the barrel. What holds the action shut while the bullet travels down the barrel is the inertia of the mass of the bolt plus an amount of spring tension. The barrel does not need to move but there's no reason why it can't, the blowback will function as long as all forces involved are properly balanced. This is blowback sometimes called direct blow back. Every semi .22 and most pistols below 9mm operate that way

IF the gun has the breech mechanically locked to the barrel and it is movement of the entire assembly that allows it to unlock, this system is called recoil operated. It is not blow back. If the system moves 1/2" or less before unlocking it is called short recoil. More than that, its long recoil.

If you were to remove the link in a 1911A1 or cut the cam off a Glock, and fire them with the barrel locked to the slide mechanically, the parts will move but the gun will not cycle because there is nothing unlocking the parts.

The system operates differently from a blowback and therefore has a different name.

Gas operated systems are mechanically locked and use gas pressure tapped off the barrel to move certain parts to unlock them. Like the blowback action the barrel is usually fixed (does not move).

Reducing things to their most basic doesn't do justice to the descriptive nature of the names or why we use them.

The 2 cycle motorcyle engine, the 4 cycle engine in your car, the diesel in a semi truck, the wankel engine and the turbine engine used in jet aircraft all operate on the same basic principle ignition of a volitile fuel. The way they do it is different, and we use different names/terms to reflect that.

Just as we do with firearms.
 
but why does using the mass of the slide as a mechanism to delay on a direct blowback not constitute a mechanism, albeit a simple one? it mechanically holds the cartridge in place long enough to allow the pressure to decrease before the slide or bolt can operate.

I was separating recoil and gas operated. Yes both are operated by gas in a sense With one having the recoil cycling the action, the other the gas operating an independent mechanism to unlock and operate the system. would gas then be considered a gas delayed recoil system?

If this is the case would it be broken down into just manual and gas operated in its simplest forms?

Industry terminology is there so that things can be marketed, new technology, advances. I'm interested in what things are, not marketing.
 
but why does using the mass of the slide as a mechanism to delay on a direct blowback not constitute a mechanism, albeit a simple one?
Click to expand...

It does constitute a mechanism, and that mechanism is called the blow back action.

Its called such because the bolt/slide is not physically, mechanically locked to the barrel, and is "blown back" by the pressure of the gas, AFTER holding shut long enough (through inertia, primarily) for the bullet to leave the barrel, pressure to drop enough for the case to spring back from the chamber walls and be extracted.

the gas operating an independent mechanism to unlock and operate the system. would gas then be considered a gas delayed recoil system?
Click to expand...

No, because the gas operation is completely independent of recoil. And. there's nothing to "delay" Consider for a moment, if you were in zero gravity, the recoil systems would probably not work reliably, if at all, as they do require something to "push against" and if you were in space the only thing to push against is the inertia of the mass of the gun and the person holding it. A gas operated system uses the pressure of the expanding gas to push against various parts of the gun, so should operate normally.

Think "limp wristing" a recoil operated pistol. You cannot "limp wrist" a blowback system and cause it to fail, nor does that affect a gas operated system. SOME recoil operated systems will function with the gun barely held or even not held at all, some systems will not.

Industry terminology is there so that things can be marketed, new technology, advances. I'm interested in what things are, not marketing.
Click to expand...

No, Industry terminology exists so that people in industry know and recognize what they are talking about. So that everyone is "on the same page" about things. So things can be made to uniform standards.

Advertising and Marketing terminology is there for marketing and sales. Marketing will often use the industry's terms, but there's a significant difference.
 
Externally powered, i.e. Gatling guns, chain guns (GAU-8 in the A-10), driven by an external electric motor might be different from "manual". Especially since the person firing the weapon may well not be touching the weapon. One would think "manual", implying "hands", would require touching.
 
Let me start by saying that I find the adoption of the "change my mind" meme as being a counter productive means of discourse by asserting a dominant stance and requiring it be overcome. Hopefully this pretty simple question won't turn into that.

Your taxonomy is regressive to the way that we have defined firearms as they have become more complex systems. Technically, if we reduce everything down to the level you should have, recoil and gas should share one platform. They both use the energy of expanding gas to mechanically extract, eject, feed, and set the action. Under your own taxonomy they're no more distinguishable than blowback vs. recoil.

In this case then you'd actually be back at 3 because there is one immediately which you've forgotten and has been pointed out above, which is mechanically driven guns. This would include rotary guns such as the GE/Dillon M134 or GAU 8 as pointed above but also chain guns such as the 25mm chain gun found on some IFVs. I'm sure I'm missing some other examples as I'm trained in arms, not ordinance. Of course you could argue that these are just an offshoot of manual guns, but you could also reduce it to the point that there is only one action type for a gun - expanding gas pushing projectile(s) out of confined chamber.

So you'd have
  • Manual guns
  • Guns cycled by cartridge pressure
  • Guns cycled through exogenous mechanical force

And maybe the Gyro Jet would be a 4th if you consider a rocket engine to be separate to a cartridge case.

This view is only helpful as a very, very high level over view of thin action types - what would commonly be broken down into manual repeaters and auto loaders. It's a start but absolutely not a useful technical system for describing anything past that.

In gunsmithing school we had to write a step by step cycle of operations (every single spring that compressed or part that moved, in order) for common and basic firearm types: break open single/double barrel breech loaders, bolt action rifles, lever action rifles, revolvers, semi auto pistols, semi auto rifles.

Even this fairly extensive project was highly reductive of the actual classification system of the varied firearms that exist. Take for example semi-automatic rifles:
  • straight blowback
  • delayed blowback
  • toggle locked
  • recoil operated
  • inertia operated
  • gas operated
  • primer actuated
Take delayed blowback: roller delayed, lever delayed, radial delayed?
Gas operated: direct impingement, piston, gas trap? Short or long stroke piston? Open or closed bolt? Rotary bolt, tilting/falling block?

In my attempts to reduce the answer of "what is a gun?" to its essence, I've come up with the following: a tool for converting chemical energy into kinetic energy to propel a projectile out of a confined space in a controlled and directed manner.

All of your 3 classes can be reduced into my definition of "gun". But we classify things so that we can compartmentalize them for meaningful reference, comparison and discussion. That's what I think it is that your system misses. It doesn't serve a useful purpose for compartmentalization for any practical uses outside of your own, or maybe as a stepping stone for a teaching tool. It is not specific enough to separate the meaningful distinctions needed for practical application of a taxonomic system.
 
Dakota, very interesting. My apologies in my wording. I am trying to go down the theoretical process of breaking down the action types based on a discussion that kind of went a bit off the rails in another thread.

My goal was to break firearms down into their base systems. I understand firearms are becoming every more complex. But am wanting to understand them a more defined sense than just firearms, but less specific than redial delayed blowback.

I'm torn on mechanical. I am unsure as to whether that should be its own category, or a subset of manual. While there is no direct input of the user in the action of the firearm, the user does have to activate the mechanical system to operate the firearm....

I do like the term guns cycled by cartridge pressure, much better than blowback or recoil operated

This would leave us with
Manual
Operated by cartridge pressure

I am still struggling to understand the difference between straight blowback and delayed blowback, as the mass of the slide is used to delay the opening of the firearms. It is still a function in the design of the firearm, despite not being a separate mechanism like a roller lock. would not that still be a very simple delaying mechanism, thus qualifying it as a delayed blowback?
 
Shadow9mm said:
I am still struggling to understand the difference between straight blowback and delayed blowback, as the mass of the slide is used to delay the opening of the firearms. It is still a function in the design of the firearm, despite not being a separate mechanism like a roller lock. would not that still be a very simple delaying mechanism, thus qualifying it as a delayed blowback?
Click to expand...
Careful -- you'er tip-toeing up to another minefield.

If you regard slide mass as a delaying "mechanism," then we have to discuss the distinction in delayed blowback pistols between locked breech and unlocked breech. The 1911, for example, is a locked breech action. But the .22 LR 1911 conversions are not locked breech, nor is the scaled-down Browning 1911-380 or the Llama Micromax 380/Armscor Baby Rock.
 
Don't be too hard on ol' shadow, there was even a Beretta advertising writer who thought a M92 was "blowback."

Misnomers and neologisms are very common in the Internet Age, it is easy to spread your own version around.

Dakota lists a number of operating systems. Obviously their designers thought them suited for the application. Or maybe they had to come up with something not covered by another designer's patent.
Would John Pedersen have designed some of the stuff he did if John Browning did not already have a working system?
Would Winchester have made the 1911 shotgun the "Widowmaker" cocked by a knurled band on the barrel if Browning had not written the A5 patent so comprehensively that the bolt handle was a patented feature?
Did Searle really think that inclined oiled surfaces would first stick together, then release under sudden pressure? He sure sold it to Thompson and Savage.
 
Originally Posted by Shadow9mm
I am still struggling to understand the difference between straight blowback and delayed blowback, as the mass of the slide is used to delay the opening of the firearms. It is still a function in the design of the firearm, despite not being a separate mechanism like a roller lock. would not that still be a very simple delaying mechanism, thus qualifying it as a delayed blowback?
Click to expand...

Again...no. The confusion seems to be from where you are applying the term "delay". So, lets try and clear that up.

Every firearm holds the breech shut when the round is fired. AND they hold the breech shut for a brief period of time AFTER the round ignites. The time required for the bullet to leave the barrel, and the pressure to drop to a level safe to release into the action when it opens.

This is NOT "delay". It may seem like it, and from a pure linguistic point of view it is "delay" because the breech does not open the instant the round fires. But the breech is not supposed to open the instant the gun fires (that would be dangerous) so the time interval between firing and opening is not considered a "delay".

The time lag between the cartridge igniting and the action opening is a required, necessary part of firearm function. It MUST happen or you get a face full of high pressure gas and probably brass fragments.

Since that must, and does happen with EVERY GUN, every time it fires, it is not considered a delay, it is proper operation.

SO, now more specific, to blow back and delayed blow back.
You understand the blowback holds the breech shut for a brief period of time (as designed for safety) using inertia and spring tension. Bolt mass and spring tension are calculated and balanced against the force of the gas pressure so this happens.

A delayed blowback (aka retarded blowback) does the same thing, BUT uses something to slow down the opening of the breech so that it opens after it would with a straight blow back system.

This is most often done with a dimpled or fluted chamber, which means the brass case grips the chamber slightly longer before releasing, which means the blowback is slightly delayed in time from when it would have opened without the fluted chamber (or whatever system is used).

IN effect it holds the breech shut LONGER than a straight blowback. It delays the opening COMPARED TO a straight blowblack action.

This is done to allow the use of higher pressure rounds than the straight blowback can handle and/or to allow the mechanism to be "differently balanced" against the gas force, and achieve safe, reliable function.

As an example, lets say we built a blow back gun for round X, and in order to hold the breech shut long enough, the bolt has to weigh 2 pounds to have the inertia needed.

Now, if we retard the blowback, spreading the "push" from the powder gas out over a longer period of time before movement happens, by using something like a fluted chamber, we can tinker with the balance of forces.

Meaning that bolt mass (and spring tension on it) may be adjusted (changed) and still do the job needed. IF a straight blow back needs a 2lb bolt to work, a delayed blowback system may only need a 1.5lb bolt in order to work with the same pressure cartridge. (numbers for illustration purposes only)

This allows designers the flexibility to either make the gun ligher, or keep it where it is for mass, and use a higher pressure round.

The designs not only have to work, they also have to be light enough that people will use them.

SO, a delayed blow back is only "delayed" in comparision to when a straight blow back would open. ALL guns are 'delayed" from opening the instant the cartridge ignites, by intentional design and therefore are not considered "delayed".

Clear as mud now?? :D
 
Here's definition standards from SAAMI's glossary ......

BLOWBACK ACTION
An automatic or semiautomatic action that utilizes the expanding gases of the ignited propellant powder to drive the breechblock action rearward. In other firearms the breechblock holds the breech closed under the force of the recoil spring, no mechanical locking system being employed. In a blowback action, the inertia of the movable parts is such that the bullet leaves the muzzle after discharge before the breechblock moves rearward.

GAS OPERATED ACTION
An automatic or semiautomatic type firearm in which the propellant gases are used to unlock the breech bolt and then to complete the cycle of extraction and ejection. This is accomplished usually in conjunction with a spring which returns the operating parts to battery.
Also Known As: Gas Operated

RECOIL OPERATED ACTION
A self-loading type firearm in which the force of recoil is used to unlock the breech bolt and then to complete the cycle of extracting, ejecting and reloading.
Also Known As: Recoil Operated
 
If you want to break things down by what actually operates the gun to eject the empty and load another one, your categories are decent.

As mentioned, you probably need to add one for electric drive which has characteristics of a manual drive but obviously isn't really manual.

Also, I think that you probably need to make allowances for hybrids. The gas-delayed guns are an example. They need the gas to function safely but the action is operated by blowback/recoil.

As mentioned your use of the term 'action' is a bit non-standard, but the rest of your question makes it clear what you mean.
Every firearm holds the breech shut when the round is fired.
Click to expand...
Advance Primer Ignition actions actually fire the round before the breech is fully closed.
 
Shadow, I think you may have almost thought yourself to the logical conclusion of this question. You're trying to define how a measured powder charge and projectile gets loaded, fired, ejected, and then the next measured charge and projectile gets positioned to repeat the cycle.

We have fixed ammunition firearms (muzzle loaders) and cartridge firearms (we'll skip the exotic variants for now).

You've in essence defined the root of how these firearms are cycled. There are those which rely on manual action to reload them, and those which harness and redirect some energy of the cartridge operation to affect the loading cycle. That's pretty much as simple as the classification can get. I think your quibbles with recoil vs. gas operation were something of a red herring which kept you from realizing you had not yet reached the conclusion of combining them both into firearms operated through excess energy of cartridge ignition.

As far as your questions concerning straight blowback vs. delayed, if it helps, consider it a question of overcoming a direct resistance in the form of a spring vs. overcoming mechanical interference, typically in the form of dispersing energy in a non-linear direction. But of course even this will have degrees. For example, the wedge in the action of a Thompson is much closer to the resistance provided by a spring and bolt alone, whereas the roller system of HK style firearms has a locking wedge pushing rollers into abutments in the trunnion which must retract before the bolt can move. For this reason, delayed systems that employ this kind of mechanical interference are sometimes referred to as a semi-locked breech or a semi-rigid locking mechanism.
 
Hmm. I might change the format.
I'd go with broad classifications then sub sets Like Order,Phylum,Genus,species.

But thats about as far as I want to take it. I'm selective about melting my brain cells,and I do not feel compelled to order the world.

A hint: The old Gun Digest,Guns Annual,and Shooters Bible had a way of cataloguing all the commercially available firearms.

It was a workable system.
Rifle Handgun Shotgun
Etc,Etc Etc

Small Arms of the World did,too. More Military Nomenclature.

"Hand held shoulder fired breech loading clip fed gas operated semi automatic rifle"
 
If it aint broke; don't fix it !!!

I will grant people have put all kinds of special names on things and tried to be very specific within the sub catagories, but everything falls under one of these 3. "change my mind."
Click to expand...
Given your train of thought, you must have some interesting conversation on firearms. At some point, you would have to narrow it down to the current and logical terms. ....... ;)

but everything falls under one of these 3.
Click to expand...
No they don't !!!

"change my mind."
Click to expand...
No, I wont. !!!

Be Safe !!!
 
"...the energy of the cartridge..." Cartridges have no energy. Potential or otherwise. The gun powder does. Nor do they 'create' recoil. That's simple physics.
The gasses in the barrel to unlock and cycle the action do not do anything but propel the bullet. In gas operated firearms, some of the gasses created by burning the powder are used to cycle the action. That happens long after the gasses in the barrel are gone. Recoil starts the microsecond combustion starts in the case.
"...change my mind..." Read some books.
 
T. O'Heir said:
"...the energy of the cartridge..." Cartridges have no energy. Potential or otherwise. The gun powder does. Nor do they 'create' recoil. That's simple physics.
The gasses in the barrel to unlock and cycle the action do not do anything but propel the bullet. In gas operated firearms, some of the gasses created by burning the powder are used to cycle the action. That happens long after the gasses in the barrel are gone. Recoil starts the microsecond combustion starts in the case.
"...change my mind..." Read some books.
Click to expand...
What books would you recommend? Where should I start?
 
Cartridges have no energy. Potential or otherwise. The gun powder does. Nor do they 'create' recoil. That's simple physics.
Click to expand...

Conventional nomenclature refers to a cartridge as an assemblage of case, primer, powder and projectile.

It's also inaccurate to say they don't do anything but propel the bullet. The expanding gases also push the cartridge rearward against the breech face. In blowback, delayed blowback, and recoil operated firearms this rearward impulse cycles the mechanism. Also indirectly true of inertia-locked systems.

So it's still correct to refer to firearms broadly as either manually operated, mechanically operated, or operated as a result of energy created by cartridge ignition.
 
....Here's definition standards from SAAMI's glossary ...
Click to expand...

Remember that firearm design, engineering, and nomenclature are pretty mature bodies of knowledge.

Firearm related terms in general have well accepted and understood meanings. Trying to create a new firearm lexicon will probably not be very productive or useful.
 
You must log in or register to reply here.
Back
Top