[Higgins]

I posted this in response to a thread over on another forum and got no responses, so I thought I'd post it here to see if anyone has any thoughts:

Could the Benelli recoil/inertial unlocking system used in their shotguns be engineered to work in a handgun the way HK miniaturized the roller-locking system of the G3 for handguns?

While we're at it, could somebody explain to me (like I'm a five-year old) exactly how the Benelli recoil/inertial unlocking system works. Never have seem enough info to really understand how it works. Thanks.

[mete]

They go by various names but they are all what are refered to as delayed blowback. The HK G3 series and P7 and P9 pistols ,the old remington M51, the Benelli shotguns and pistol etc. The HK G3 and P9 are roller delay, P7 is gas delay, M51 is momentum block. .... The Benelli system has a two part bolt . The breech bolt moves slightlywhen you fire, this compresses a stiff spring between breech bolt and bolt body. The momentum is then transferred to the bolt body which then moves backward and unlocks the breechbolt. The breechbolt and body then move backward to extract the shell. This operation takes time (thus "delayed" blowback) and the shot has left the barrel before the unlocking takes place. It's all physics 101.I know it works well because I have one . Benelli does or did make a pistol though I'm no t familiar with the details of operation.

[DMK]

Isn't that similar to the way the CZ-52 works?

[mete]

The CZ-52 has a roller delay like the HK G3 and P9.

[45crittergitter]

http://www.thehighroad.org/showthread.php?s=&postid=631712#post631712

[Jim K]

Benelli made/makes pistols using the inertial system. I have a B76 in 9mm that works fine. These do indeed allow a small bolt movement to provide the initial energy, as Mete says.

The shotgun, however, does not work quite that way. If you look at the diagram in the ads, you see a heavy block shaped to fit inside the receiver. Between the block and the bolt is a heavy spring. When the gun is fired, recoil drives the gun back. The block, obeying Mr. Newton, is a body at rest and tries to remain where it is, which means it moves forward in relation to the receiver and compresses the spring. When the recoil force stops, the spring drives the block backwards, unlocking the bolt and pulling it back to extract and eject the empty case. A conventional return spring brings the block and bolt back into battery, picking up a fresh shell from the magazine on the way.

It is an ingenious system and eliminates many of the problems of other type shotgun actions, like friction rings, dirt from gas, etc.

Jim

[mete]

Jim, your explaination is more correct, but it does work.