The BRG-15 had conventional, gas operated action with rotating bolt, locking into the barrel extension.
该担心现有- 15接受传统，燃气经营与旋转螺栓行动，延长锁入桶。
2
In this action bolt has two frontal lugs that engage the barrel extension, which is screwed onto the barrel.
螺栓在这次行动中有两个是从事前沿耳桶扩展，这是到每桶拧。
3
The testing methods on extension of anchor bolt are introduced. The whole deformations of normal bolts under pretensioning and its effect on the jacking of surrounding rock are pointed out.