Originally Posted By HelpfulGuerilla:
Oh man!  My rifle only fires once in the enhanced position, and then it has a dead trigger/hammer follow/failure to fire!  I'm using an H3 buffer!

Let's help you all out and learn about bolt bounce in the process.

The bolt carrier can bounce off the barrel extension a very small amount before the hammer strikes the firing pin.  We believe that the deadblow mass ratio is more important than the overall mass of the buffer.  Changing to a heavier buffer spring may or may not solve a bolt bounce issue for you.  In fact, it may even make it worse.  When we did our 5.56 carbine testing protocol, we used a lot of LBE, Geissele, and Noveske buffers among others.

For 5.56:  If you plan on using a traditional buffer, please use an aluminum bodied H3 buffer with 3x sliding tungsten weights.  Some buffers use steel bodies and steel weights because it is cheaper than using tungsten.  Our troubleshooting page has a short video on how to tell the difference and what to look for.  It is not enough to look at what is stamped on your buffer or rely on what the manufacturer claims that it is. You may have to disassemble your buffer to be completely sure, as stainless steel is nonmagnetic, and plenty of deadblow/shakeweight cheaper buffers will have (usually) two reciprocating weights inside.  The price of tungsten has increased substantially, and we hope that we played a significant role in it, so you have to look at what you are getting when you order a buffer.  If the price is too good to be true, that's because it is.

We recommend an H3 buffer because it will slow the cyclic rate enough to allow the magazine more time to keep up with the enhanced rate of fire.  Additionally, you can use an existing carbine buffer and an H3 to make an H2 if you decide that works better for your ammunition and rifle setup.  Some setups will work with H1 or H2 buffers, but there's no guarantee, and it seems that the H3 choice solves the vast majority of issues across the widest range of firearms.

We do not recommend solid buffers or powdered tungsten buffers.

We do not recommend the Kaw Valley stainless steel buffer as we believe that it does not have enough deadblow mass.  

We do, however, recommend the excellent Tromix Auto/RRT buffer, and many users report success with the Odin adjustable buffers.

For rifle length extensions, we have found that the standard rifle buffer is usually sufficient.  The A5 system works great in A5 buffer tubes with an A5H2.  Both of these heavier systems will slow your rate of fire and make your rifle more controllable.

This video is made by an individual that is unaffiliated with us, but it has some very good information on buffer and spring tuning: https://www.youtube.com/watch?v=hIPaBanf0_M

For 9mm:  We recommend starting with 124gr ammunition and 10oz of buffer weight to start and then tune from there.

Originally Posted By leemozoid:

Doesn't matter which ammo or buffer you use in a 9 mm if the bolt isn't catching the trip and the hammer follows it back k into battery.