A company called Armament (yes, simply Armament) manufactures an AR-15 buffer called L.A.R.B. (Linear Alignment Recoil Buffer). When you look at this buffer, you can immediately notice its enlarged tail portion. That allows having the second point of contact with the buffer spring and provides better alignment of the buffer and spring inside the buffer tube.
Among other features of the L.A.R.B. is the bulged buffer face. That protrusion goes into the bolt carrier tail and prevents the BCG tilt in gas piston operated AR-15s. According to the owner of the company – Nick Barry, the buffer still allows normal field stripping by pivoting the upper receiver. It does not require to pull out both disassembly and takedown pins and move the upper receiver forward to make that bulged portion come out of the bolt carrier.
Another difference from the stock buffer is that the weights inside the L.A.R.B. are under constant spring pressure (see the image below). That feature eliminates the rattling noise of loose weights. However, it still allows the weights to move forward and compensate the BCG bounce.
The polymer tip is also redesigned. It is made of a different polymer and makes the buffer impact softer working like an additional recoil mitigation measure.
The company has conducted several tests with the conventional and L.A.R.B. buffers. The results are shown in the graphs below.
I’ll quote Nick Barry’s explanation of the graphs:
The graphs show how well the buffer as an assembly slows the recoil impulse. This was recorded using an accelerometer placed on a 10.5″ suppressed SBR. Rounds were fired with a stock H mil spec buffer, the same ammo fired with my LARB H buffer. The graphs show how my buffer literally takes the edge (sharp recoil spikes) off the recoil. The graphs show both semi auto fire and full auto fire. I have shown via shot timers, to slow the ROF on a select fire M4 up to 30% with simply installing the LARB. The LARB is so good at reducing the sharp recoil (basically “felt recoil”) that everyone who shoots it comments on how fast follow up shots are.
Here are also a couple of videos showing full auto firearms being shot with the L.A.R.B. buffer installed:
This buffer has other features too, which are listed in the image below.
The L.A.R.B. is machined out of a solid bar of 17-4 stainless steel. It is a drop-in part. The buffer is made in the USA and covered by a lifetime warranty. It weighs 4 oz (H weight). The MSRP for the H-weight is $75. They also plan to introduce an H2 weight buffer at an MSRP of $95 and an adjustable weight kit (3oz to 6oz) which will be sold at $45 price.
To me, this is yet another good example of an innovative product made by a small company. It is impressive how many new features the designers managed to include in a single simple part like the AR-15 buffer.