Hydraulic Buffer info with the amount of force required to compress.
As you can see the original carbine Enidine and standard Kynshot RB5000 are in the 9lb range to compress. I’ve never really been impressed with either one and was about to give up on the hydraulic buffers.
If you look at my full auto testing link, note that most springs have 7 to 13 lbs of force on a closed bolt. I have a theory that these stiffer hyrdaulic buffers aren’t doing anything on the initial recoil impulse and don’t do anything unless the BCG is slamming into the users shoulder.
I think that for a gas operated gun, step 1 is to make sure the gun isn’t overgassed first with I’d say an H2 buffer. Then start looking at buffer, buffer tube and spring selections.
In the case of a straight blowback pistol caliber not much you can do other than throwing mass at the problem which then makes the gun bouncy. On the CMMG RDB, bolt lug angles can be changed to control the delay instead of throwing mass at the problem.
All that said, I think a good use case for these first two buffers would be where you have violent action you can’t control the gas or straight blowback.
I think the RB5005 is a good choice for someone that has a carbine length buffer tube and doesn’t want to go to an ‘A5′ length buffer tube. I would recommend this buffer alongside a 556 Tubb flat spring for most configurations. If running a CMMG RDB 9mm, going to the 300BLK Tubb flat spring will drop the cyclic rate about another 30 RPM slower.
With the RB5005 and RB5007, I believe that the hydraulic action is actually absorbing some of the initial recoil impulse and may also compress again on the rearward stroke depending on the configuration. Also compresses some when chambering. I think this also explains the drastic cyclic rate reduction seen with these buffers especially suppressed.
A5 Buffer Weights
H0, 3.8 oz
H2, 5.33oz (Default weight, also what the original A5′s came with)