kalibear45
Member
Or are they all similar?
What's the difference between blow back & recoil operated handguns?
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critter
Member
No 'ex-spert' here but I'll try. Simple 'blowback' guns do not have a locked slide. The recoil of the round simply pushes the slide back to accomplish extraction, ejection and feeding. There must be a careful balance between weight of the slide, strength of the recoil spring and power of the round for the arm to function. Due to the needed slide weight and spring force needed, these are usually limited to rounds less powerful than the 9mm.
'Recoil operated' have the slide locked in some way as in 1911's where the barrel and slide are locked together for part of the cycle by lugs on the barrel and slide. The swinging link keeps them together for a bit then unlocks them for the balance of the recoil part of the cycle. Various other arms use various means of lockup. Some do not have a swinging link but a odd shaped hole or slot in the barrel underlug that does the same thing. Many lock the back part of the barrel in the ejection port of the slide for a time till unlock happens. These guns also must have slide weight, spring strength and round power balanced but they probably are not at such a critical and small window balance as the simple blowback ones. More powerful rounds can be used in locked breech guns if everything is 'balanced' correctly, thusly the 9mm, 45 acp, 40 s&w, .357 sig and even 44 mags, 45 win mag, etc.
Hope I helped without muddying the waters to much and maybe more experts will weigh in with better info.
'Recoil operated' have the slide locked in some way as in 1911's where the barrel and slide are locked together for part of the cycle by lugs on the barrel and slide. The swinging link keeps them together for a bit then unlocks them for the balance of the recoil part of the cycle. Various other arms use various means of lockup. Some do not have a swinging link but a odd shaped hole or slot in the barrel underlug that does the same thing. Many lock the back part of the barrel in the ejection port of the slide for a time till unlock happens. These guns also must have slide weight, spring strength and round power balanced but they probably are not at such a critical and small window balance as the simple blowback ones. More powerful rounds can be used in locked breech guns if everything is 'balanced' correctly, thusly the 9mm, 45 acp, 40 s&w, .357 sig and even 44 mags, 45 win mag, etc.
Hope I helped without muddying the waters to much and maybe more experts will weigh in with better info.
Critter has the basics. Blowback is for low powered cartridges, 22 to 380. Only the slide weight and recoil spring resist the force.Locked breech (or delayed blowback like the HK P7 ) are needed for the more powerfull ones . The more complex mechanism of the locked breech is larger and more expensive. For guns of the same weight and cartridge a delayed blowback will have the least felt recoil ,next locked breech , and the blowback will have the most felt recoil.
kalibear45
Member
Thats what I thought. Thanks! 
BluesBear
member
Close.
All semi-automatic firearms are either recoiled operated or gas operated. Almost all semi-auto pistols are recoil operated. The Automag, the Wildey and a few others are gas operated. Most high powered Semi-auto rifles are gas operated. .22 rimfires and most pistol caliber carbines are recoil operated.
Perhaps you are referring to blowback vs locked breech pistols. If so then what Crutter said is basically correct. if a pistol has a barrel that moves a short distance with the slide before it unlocks is a locked breech type. Glocks, 1911s, Hi-Powers, S&Ws and such are this type.
Walther PPK's, Ruger MKIs and most other .22, .32s, .380s are blowback.
High Points are also blowback pistols.
As far as delayed blowback or retarded blowback pistols...
There really ain't no such animal. Either it's locked or it ain't.
All semi-automatic firearms are either recoiled operated or gas operated. Almost all semi-auto pistols are recoil operated. The Automag, the Wildey and a few others are gas operated. Most high powered Semi-auto rifles are gas operated. .22 rimfires and most pistol caliber carbines are recoil operated.
Perhaps you are referring to blowback vs locked breech pistols. If so then what Crutter said is basically correct. if a pistol has a barrel that moves a short distance with the slide before it unlocks is a locked breech type. Glocks, 1911s, Hi-Powers, S&Ws and such are this type.
Walther PPK's, Ruger MKIs and most other .22, .32s, .380s are blowback.
High Points are also blowback pistols.
As far as delayed blowback or retarded blowback pistols...
There really ain't no such animal. Either it's locked or it ain't.
New_comer
Member
'tween critter's and BluesBear's def'n, I'd go with Blue's...
Blowback action is obviously a consequence of the recoil caused by the fired bullet. I also think that all blowback pistols have fixed barrels. That said, a P7 is a 'modified' blowback, with the fired gases being bled in a special 'recoil' chamber to activate the slide, several moments after ignition.
OTOH, locked breech pistols have moving barrels, to add resistance and mass to dampen the initial recoil. A relatively small residual force remains as soon as the barrel reaches its most rearward motion, that pushes the slide rearward still, just enough to cycle in a fresh round in the chamber and restore the interlock between barrel hood and slide's breechface.
Have I muddled the issue even more?
Blowback action is obviously a consequence of the recoil caused by the fired bullet. I also think that all blowback pistols have fixed barrels. That said, a P7 is a 'modified' blowback, with the fired gases being bled in a special 'recoil' chamber to activate the slide, several moments after ignition.
OTOH, locked breech pistols have moving barrels, to add resistance and mass to dampen the initial recoil. A relatively small residual force remains as soon as the barrel reaches its most rearward motion, that pushes the slide rearward still, just enough to cycle in a fresh round in the chamber and restore the interlock between barrel hood and slide's breechface.
Have I muddled the issue even more?
jar
Contributing Member
SiG 230, classic blowback. Note the fixed barrel.
CZ100B
Member
I was going to say the CZ-52 is a true delayed blow back, but it actually isn't. The barrel is not fixed to the frame.
Like the photo above shows, if the barrel is fixed to the frame, it's a blow-back pistol, otherwise it is some variation of locking barrel recoil operation.
Then there are a few gas-operated pistols (like the Desert Eagle) that function comletely differently
Jeremy
Like the photo above shows, if the barrel is fixed to the frame, it's a blow-back pistol, otherwise it is some variation of locking barrel recoil operation.
Then there are a few gas-operated pistols (like the Desert Eagle) that function comletely differently
Jeremy
Chipperman
Member
"As far as delayed blowback or retarded blowback pistols...
There really ain't no such animal."
The HK P7 series (with the exception of the P7K3) use a piston to delay recoil until the pressure decreases. So, why would you not call that "Delayed Blowback"
There really ain't no such animal."
The HK P7 series (with the exception of the P7K3) use a piston to delay recoil until the pressure decreases. So, why would you not call that "Delayed Blowback"
AZ Jeff
Member
The HK P9 series pistols are true delayed blowback, using the same roller "locked" breech system from their rifles.
Delayed blowback guns do exist though different makers may call them retarded blowback or other names. They include the momentum block Remington 51, HK roller block P9, gas retarded P7 ,roller block CZ 52 ,the entire HK G3 series in rifles, Benelli shotguns, and others. The basic difference in the delayed blowback is that the breechbolt starts to move immediately but is slowed considerably by retarding mechanism. And they all work very well.
Hi, guys,
New_comer has it almost reversed. Blowback operated firearms operate solely from the pressure in the cartridge case. In one direction, it pushes the bullet out of the barrel, in the other direction it pushes the fired case back against the breechblock. In a pure blowback, only the mass of the breechblock keeps the breech closed until pressure drops enough to prevent the case from being blown apart. It is also this mass that keeps the slide from moving as fast as the bullet; if the slide weighed the same as the bullet, it would move as fast and (barring some stop) as far.
In a recoil-operated locked breech system, the type used in most higher power pistols, it is the recoil from the bullet's forward movement that drives the barrel and breechblock, locked together, to the rear. Some mechanism outside the barrel/breechblock unit disconnects the barrel from the breechblock after the pressure has dropped and allows the breechblock to cycle, extracting and ejecting the fired case and, when the recoil spring asserts itself, to pick up a fresh round from the magazine and chamber it. In a recoil operated system the gun will not operate if the bullet does not move; if the barrel is blocked to prevent bullet motion, the gun will not function.
Jim
New_comer has it almost reversed. Blowback operated firearms operate solely from the pressure in the cartridge case. In one direction, it pushes the bullet out of the barrel, in the other direction it pushes the fired case back against the breechblock. In a pure blowback, only the mass of the breechblock keeps the breech closed until pressure drops enough to prevent the case from being blown apart. It is also this mass that keeps the slide from moving as fast as the bullet; if the slide weighed the same as the bullet, it would move as fast and (barring some stop) as far.
In a recoil-operated locked breech system, the type used in most higher power pistols, it is the recoil from the bullet's forward movement that drives the barrel and breechblock, locked together, to the rear. Some mechanism outside the barrel/breechblock unit disconnects the barrel from the breechblock after the pressure has dropped and allows the breechblock to cycle, extracting and ejecting the fired case and, when the recoil spring asserts itself, to pick up a fresh round from the magazine and chamber it. In a recoil operated system the gun will not operate if the bullet does not move; if the barrel is blocked to prevent bullet motion, the gun will not function.
Jim
Mete: I disagree that the Benelli/Beretta shotgun action is delayed blowback or retarded blowback in any sense of the word. The rotating bolt head locks into the bbl extension and does not unlock until the bolt carrier under force of recoil loads the heavy spring and bounces back. It's a recoil action, just accomplishing its work thru different means instead of the bbl moving the moving part is the bolt carrier. Same o same o.
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