When it comes to the failures of the AR-15 locking mechanism, you normally see the failure of the bolt. I bet you have seen bolts with one or two or as much as all seven locking lugs sheared. In this article, we’ll take a look at something different – a rather rare barrel extension failure.

I came across the images of this rifle in one of the online firearm communities. As you can see, a ring containing the locking recesses of the barrel extension has been separated from the extension itself. According to the owner of the rifle, he didn’t experience catastrophic destruction of the rifle or any injuries. The gun just didn’t cycle and after inspecting it, he found out this unusual breakage of the barrel extension.

Although it is not known/proven what exactly caused this destruction, it is most likely caused by an improperly heat treated barrel extension. Before the failure occurred, the rifled functioned flawlessly and had thousands of rounds fired through it. The ammunition used when the failure happened was PMC 5.56x45mm NATO. The barrel of this rifle has a marking “BHW” which stands for Black Hole Weaponry. Apparently, BHW is now the subsidiary of Columbia River Arms. The owner of the rifle contacted the company and reported that the customer service was great and they will replace the barrel.

Letters BHW can be barely seen on the barrel

It is the first time I ever see this AR-15 part to have this kind of breakage. Have you ever encountered such a barrel extension failure? In general, what do you think about this weird failure? Do you think this is a heat treatment issue or do you have another theory? Share your thoughts in the comments section.

Many thanks to Steve S., the owner of the rifle, for the permission of using the photos.