I just noticed a fun video by Forgotten Weapons that they posted back in July. The AR-15 forward assist is a control on America’s most ubiquitous rifle, yet almost no one appears to know what it is for. I’ve seen a supposed expert say that it just makes them feel good to press it every now and again. The attached video is a complete history of this nearly-useless feature, but I’ll go ahead and clear it up for you.
A forward assist is something that can be used to jam the bolt into firing position if something goes wrong with the rifle — typically, foreign material in the chamber. The army thought they needed a forward assist because every self-loading rifle they’d fielded before had the charging handle affixed to the bolt (so it could be used as a forward assist) and they felt like soldiers needed the forward assist as a security blanket. Nobody ever studied how often a forward assist is needed — nor did they study how often using the forward assist makes things worse. In practice, if the bolt won’t go into battery without the forward assist, then once you’ve used the forward assist, the rifle will not cycle again until you’ve gone through a much more involved process to get that stuck case out of the chamber.
So when would you use the forward assist?
If you’re sneaking, and want to chamber the first round without making much noise, and you forgot to chamber a round before you started sneaking… you should not need to use the forward assist. The bolt should just go into battery even though you are riding the charging handle for the sake of quietness. However, if it doesn’t go into battery, you could press the bolt forward with your thumb on that indention on the bolt that is there so that the ejection port cover latch both clears the bolt and pops open when the bolt actuates. If that doesn’t work, something is Wrong.
If something is Wrong, and the bolt won’t go into battery, you could use the forward assist at that point, and there is a pretty good chance that will get you one more round. However, you’d be much better off pausing and clearing out whatever material is in the chamber and preventing the bolt from closing, because if you cram the next round into the chamber with the forward assist, the odds are extremely high that you’re going to get a failure to eject, and then you’re going to have to do something that takes a lot more time.
The go-to method for getting that stuck case out is called “mortaring“. If that doesn’t work (maybe because your extractor is a bit worn), then you’re on to getting a cleaning rod and a hammer and knocking it out that way. Before you use that forward assist, consider whether you have time to run a brush in the chamber or spray some cleaner into the chamber, because you’ll be in much better shape if you do that instead.
In practice, there is basically just one time you’d want to use the forward assist: You desperately need to send one more bullet right now, and that one bullet is much more important than the next 30. This situation is so rare that the forward assist is basically not necessary. Yet I still like having one.