What is delayed blowback action?

Asked by: Rachel Fernandez

Delayed blowback is a descendant of direct blowback, the simplest method of automatic firearm operation. It requires the fewest moving parts and is typically the cheapest solution. The action of the gun is held closed by spring pressure and bolt mass alone.

What is the point of delayed blowback?

This delay allows pressure to drop prior to extraction without the penalty of a heavier bolt carrier assembly. The system is similar to roller and lever-delayed blowback in that it uses the mass of the bolt carrier moving at a faster rate than the bolt head to delay the action from opening.

What does blowback action mean?

A blowback firearm uses force created by burning gunpowder to cycle the action. The gas from a blowback-operated pistol pushes the bullet down the barrel when fired. As the bullet moves forward, the slide blows back under the pressure of the fired round.

How does a delayed blowback pistol work?

Pressure inside this gas piston pushes forward on the piston rod here which pushes forward on the slide which delays its opening as long as the bullet remains in the barrel.

Is roller delayed blowback good?

The simple answer is a direct blowback gas system tends to work better for rifle cartridges. With roller-delayed blowback, you ditch any adjustability. Since there is no gas system, you can’t fiddle with things as much as you can in a direct blowback gas system.

Is a Glock a blowback?

With a metal slide and polymer frame, the GLOCK 17 Gen3 has authentic blowback action that will feel familiar to shooters of all kinds.

Is AR15 delayed blowback?

The Radial Delayed Blowback bolt looks like an AR15 bolt, but differs because the lugs are chamfered on the back of the bolt and the cam path is different. The gas key looks like one, but isn’t really a gas key. However, like the AR15, it does have a built-in ejector.

Which is better blowback or non blowback?

Non-Blowback Airguns tend to have less working parts so less to go wrong and more reliability. Non-Blowback Airguns can be more accurate since the recoil from the blowback is not a factor. Non-Blowback Airguns have more potential power and more shots per CO2 since no CO2 is robbed for the blowback operation.

Are all handguns blowback?

There have been dozens of different types of designs over the years to make a pistol do this, but probably 99% of semi-automatic pistols are either blowback designs or recoil operated.

What is striker fired pistol mean?

With a striker-fired handgun, there is no hammer present. When the slide is racked back and released forward, the firing pin remains back and under spring tension. The trigger releases this tension and allows the pin to push forward resulting in firing the round in the chamber.

What guns use roller delayed blowback?

Roller delayed blowback

What is 9mm with roller delay?

Into the bolt head it pushes these two rollers out into matching recesses in a trunnion or receiver. Where they hold the bolt fully closed. Note that when the locking pieces all the way inserted.

What is radial blowback?

Radial Delayed Blowback allows reliable operation without a heavy bolt, buffer or spring. The mechanical delay allows pressure to fall in the chamber before it unlocks. The system means less recoil, increased accuracy, and better velocity when using a suppressor.

How does straight blowback work?

The strength of the recoil spring. That resists the pressures that build up in the chamber as a pressures increase and the power of the cartridge.

What is a blowback BCG?

Pistol Caliber / Blowback – A pistol caliber or blowback BCG is one that is built to be used in an AR build chambered for a pistol caliber round such as 9mm or 45 ACP. For example, the Faxon Firearms 9mm Black Nitride Bolt Carrier Group is shaped quite differently than a standard AR-15 or M16 style BCG.

Is an MP5 direct blowback?

Until the MP5, direct blowback was by far the most common means of submachine gun operation. Examples include the open-bolt German MP-40 and the American M1A1 Thompson. One way to mitigate the disadvantages of direct blowback without resorting to the complexity of a fully locked-breech is to utilize delayed blowback.

Why is it called the MP5?

The MP5 was created within the fourth group of firearms and was initially known as the HK54. Work on the MP5 began in 1964 and two years later it was adopted by the German Federal Police, border guard and army special forces, referring to as the “MP64” or later “MP5”.

Is there a civilian version of the MP5?

The HK SP5 is the civilian version of the legendary MP5. In 2018 the time had come: a semi-automatic version derived from the HK MP5K called SP5K, featuring a short 4.5”/115 mm barrel and a handguard with integrated finger stop reaching over the muzzle.

What is a fluted chamber?

A Fluted chamber is a chamber that allows gas to leak around the cartridge during extraction. Fluted chambers are often found in Delayed Blowback firearms.

What is a bull barrel?

In rifles, it’s generally a barrel that doesn’t taper towards the muzzle. In pistols, bull barrel refers to barrels that are a thicker diameter than the factory barrel, or even that flare towards the muzzle. We also refer to flared barrels as conical barrels.

Why flute is a rifle bolt?

The main purpose of fluting is to reduce weight, and to a lesser extent increase rigidity for a given total weight or increase surface area to make the barrels less susceptible for overheating for a given total weight.

What is a Parkerized barrel?

That are have a parker eyes finish which gives them this kind of grayish black finish to them. So it kind of blends in with the rails. And the the upper and the lower.

Which is better phosphate or nitride barrel?

A nitride exterior will protect the barrel longer than a phosphate exterior finish. However, a chrome-lined, or phosphate, barrel will hold up better to sustained fire than a nitride interior. Nitride has a slight edge in accuracy and price. However, phosphate coated/chrome lined barrels are more common.

Is a stainless steel barrel more accurate?

Barrel Material Choices



STAINLESS STEEL – these barrels offer the best accuracy and precision all-round. They are slightly heavier and more costly than chrome-moly, and are most suitable for long range precision where rapid fire is less likely.

What is the most durable gun finish?

Cerakote Pros:



Probably the most rugged finish available for your firearm. Impervious to solvents, cleaners.

Do stainless steel guns rust?

Stainless steel guns can eventually develop rust overtime. Oxygen can have an adverse reaction with oxygen, forming a chemical compound that is harmful to stainless steel; steel combined with iron, water and oxygen will form iron oxide, or the technical term for rust.

Why are guns nickel plated?

Since electroless nickel plating produces a more even surface on the gun, one of its benefits is that it provides excellent corrosion resistance. Although it doesn’t provide a finish as hard as hard chrome plating, it does offer a much harder and more durable finish than the unplated firearm would have.