Forward assist

Forward assisting is the practice of moving the bolt or bolt carrier of a firearm fully forward when the return spring has not done so (or there is a chance that it will not have done so). Some firearms have a dedicated device to allow forward assisting; on others it is simply a procedure performed on the cocking handle.

The forward assist on a firearm is a button found commonly on AR-15 rifle derivatives, such as the M16 rifle, and is usually located near the bolt closure. When hit, it pushes the bolt carrier forward, ensuring that the bolt is locked. In order to ensure that the extractor is clipped around the rim of the casing, the forward assist is usually struck rather than pushed. It is commonly incorporated into standard loading procedure to prepare a firearm for firing, or to close the bolt when the firearm is excessively dirty.

Another instance where the forward assist can prove useful is when performing a stealth chamber check. Rather than letting the bolt go forward under full spring tension after verifying a round is in the chamber, the bolt can be let forward gently and then the forward assist can be used to fully close the bolt. Doing so will produce a very distinct "click" rather than the loud sound of the bolt slamming forward.

The original use was partway through the firearm's use in the Vietnam war. Before the forward assist the M16 was often carried "Locked and Loaded" that is cocked with a round in the chamber safety on, because of the noise made by a platoon, some 30 men, pulling back and releasing the bolt handle would alert the enemy of their location. The assist allowed soldiers to carry a firearm without a round in the chamber until necessary.

The forward assist had been implemented in 2007 on the MSAR STG-556, an American-made clone of the Austrian Steyr AUG assault rifle, but the usefulness of such device is questionable, since the design is not normally prone to the malfunction that led to the need of the forward assist in other firearms; in fact Microtech Small Arms Research Inc., the manufacturer of the STG-556, has dropped the forward assist on all rifles manufactured since November 2008.

The forward assist may cause the cartridge to become jammed, requiring a cleaning rod to be pushed into the muzzle of the rifle to force the casing back out of the chamber. The high pressure of a round getting hung up when fired could potentially cause an explosion in the rifle. One recommendation is to avoid using the forward assist, and instead dispose of the shell that wouldn't seat properly. The main reason a bolt carrier group (BCG) won't go fully forward is usually an excessive amount of dirt, carbon build-up, etc.

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