As action frame (. Fr. bascule: flip-flop, rocker) is referred to in the weapons technology in barrel weapons the box-shaped metal workpiece between the barrel and rear shank, which contains the parts of the lock, receives the barrel set, this locks and connects to the buttstock.
The receiver (also: system box, lock box) of the break-barrel rifle contains the lock for cocking and releasing the weapon as well as the locking mechanism for opening and closing. The barrel or barrel bundle is bent to open it. The receiver receives the buttstock, to which it is usually connected by a long screw running through the barrel and by the receiver tail running on the upper side of the barrel neck. The safety lever is usually located on the tail of the receiver. The barrel set is rotatably mounted around an axis (hinge pin) in the front part of the receiver. When open and with the fore-end removed, the barrel set can be unhooked from the receiver.
To lock the closed barrels, receivers with different locking systems have been developed. This allows the different levels of stress on the weapon when firing a shot to be taken into account. The picture shows a barrel hook locking by a simple bolt in the lower part of the push plate. The bolt is pulled back into the butt plate when the locking lever is swiveled to the side. The runs are free. When the weapon is closed, the barrel set presses on the tongue of the bolt trigger. The bolt snaps forward and locks the barrels. The locking lever strikes back to the starting position (picture).
The forearm of the weapon engages in the lock tensioner so that the locks are cocked when closing. The ejector is controlled via the ejector pins, which are cocked or knocked off with the lock, so that the fired cartridge case is ejected by spring force.
The butt of the receiver absorbs the recoil of the cartridge when firing. When the shot is triggered, the firing pin is struck through a hole in the bottom of the cartridge's primer.
The box part of the receiver is usually made from a single forged piece.
The lock, or two separate locks for high-quality side-by-side shotguns, as well as the locking mechanism, are inserted into the forging that has been prepared by milling, grinding and polishing. The receiver is often refined by engraving with arabesques or images.
The receiver carries all the controls:
- the locking lever for opening and closing,
- the safety device for securing and unlocking,
- the trigger and the trigger (s)
- Switching devices for assigning a certain barrel to a trigger or for determining the firing sequence for double-barreled shotguns with single trigger.
Like all essential parts of the weapon must be the action frame to demonstrate the officially determined attack strength, the proof marks have taken a Ballistics Laboratory.
- Christer Holmgren: Hunting weapons and shooting technology: Practice for hunters and sport shooters , Paul Parey, Hamburg; Berlin 1993, ISBN 3-490-22012-9
- Lueger 1904 entry: hunting rifles
- Meyer's 1905 entry: hunting rifle