| 摘要 |
The training or testing hunting gun has adjustable butt end and a measurement jig in which is fitted the gun barrel, with the one butt side alongside a first registering surface. The butt cover locates along a second such surface. By means of pins and holes in the butt, the position of the butt and reference marks on the registering surfaces can be related to one another. For adjustment of the butt a light cartridge and target box are used, and for successive checking of adjustment and practice of pivot movements, and electro-optic target path and light sources arranged in sequence are employed, together with photo-detectors. |
