H&K MR762A1 Forward Assist

An AR-style forward assist is a plunger that is designed to help the bolt go forward into battery in the event of the round not fully chambering. Eugene Stoner's original AR-10 and AR-15 designs did not include a forward assist. After Colt bought the ArmaLite designs and ramped up production capabilities, theirs did not either. After early military testing, the newly designated M16 was in use by the U.S. Airforce with no forward assist. The Army requested a forward assist method to be added. At this time, the Army was accustomed to infantry rifles with external charging handles like the M1 Garand, M1 Carbine, and the M14. External charging handles allow force to be applied to the bolt carrier group in both directions if necessary. Forward to chamber a round, and rearward for case ejection. Stoner's new AR designs only accommodated applying force in the rearward direction. Colt complied by adding a spring-loaded plunger that could be depressed to apply force directly to the bolt carrier group, moving forward to fully chamber the round. The plunger interfaces with ribbed surfaces cut along the side of the bolt carrier when depressed and springs back out of the way when released. This new forward assist model would go on to become the XM16E1, then the M16A1 after the official adoption by the remaining branches. All the resulting variants, including the current generation, would go on to feature a forward assist. So many people have wondered, do you really need one?

Tacfire AR-15 Forward Assist

Positives:

In theory, if the bolt carrier doesn't quite reach battery and close properly, you can just press the forward assist button to help it close all the way. Another benefit is that when trying to load quietly, the charging handle can be released slowly, then fully engaging the bolt carrier by pressing the forward assist (effectively using your own energy instead of the buffer tube spring's to reach battery). There's probably a mental positive aspect of knowing it's there in the event that you might need it.

Negatives:

Eugene Stoner's initial opinions were that of an engineer: it was unnecessary and would only add additional cost, complexity, tooling, and manufacturing time. He claimed that from all of his testing on the previous models, none of the problems encountered would have been solved with the currently proposed forward assist plunger. Some also argue that if the buffer tube spring's energy (when charged correctly) isn't enough to fully seat the round into the chamber, then you have bigger problems than what pushing on it with your hand or thumb is going to fix.

CMMG AR-15 Forward Assist

Conclusion:

It probably doesn't matter, but it's nicer to have it and not need it than the opposite. Also, most AR rifles available today (outside of original AR-10 and AR-15 clones) will come with it so there is no need to worry. Of course, there's also the possibility that the Army just preferred the M14 and didn't want to have to change. Shop All Rifle Parts
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