Chris Bartocci of Small Arms Solutions LLC has released a video, where he reviews the different types of AR-15 buffers. He discusses the evolution of the buffers in chronological order. Starting from M16 buffers and the first appearance of bolt carrier group bounce issue all the way to 9mm buffers. There are also a couple of experimental unicorns in the video such as the Colt’s prototype hydraulic buffer which never went into production. He also tells about the possible dangers and malfunctioning issues in different climate conditions when using improper buffers.

Another interesting subject is how the carbine barrel weight is related to the buffer weight. In a nutshell, the heavier barrel you have, the heavier buffer you need to use. The designation meaning and proper use of different weight AR-15 carbine length buffers are also pretty well explained. It is basically as follows:

• Unmarked (three steel weights inside the buffer). This is the standard .223/5,56 semi auto only direct impingement carbine buffer.
• H (one tungsten weight with two steel weights). This buffer is also for the rifles as the unmarked one with probably a bit improved reliability.
• H2 (two tungsten weights and one steel weight). H2 buffers are better when used with heavy barrels and long or short stroke piston operated carbines.
• H3 (three tungsten weights). This one was designed to work in Colt IAR, which has a longer and heavier barrel compared to the carbines. H3 is recommended to be used with that kind of barrels.

The correct choice of proper weight buffers is especially important in full-auto capable rifles.

Chris also discusses the different kinds of 9mm buffers and a lot more. So if you find this subject interesting, you can learn more by watching the video: