1) Heavier buffer does not necessarily equal less felt recoil.

2) The proper weight buffer is dictated by the gas port diameter and ammunition.

3) Mid-length gas carbine can be made to work quite smoothly with buffers ranging from standard weight (~ 3.0 oz) to H3 (~5.4 oz)

 

I am now a firm believer in the BCM MkII buffer system. This is the SMOOTHEST shooting and recoiling rifle I have. Since doing this one, I have done my FNM4 as well.
The system uses a slightly longer buffer tube, and a Rifle buffer spring along with heavier buffers. This A4 will dump every spent case at 3:30 position into a neat little pile. My M4 use to throw the brass up at 12:30-1:00 it was so overgassed; but now it too is at a nice proper 3:00 position and the recoiled impulse feels so much better and the rifle is not beating itself up.

 

I use a tungsten T2 buffer from Spike's Tactical. No issues and it really smooths out the recoil. My rifle is a 16" BCM mid-length gas system. There's a noticeable difference when compared to a standard carbine buffer.

Tony.

 

I use H2 buffers for most of my midlength barrels.

 

Before I switched my mid length systems over to the B5 buffers, I ran H3 weights in my carbine length weapons. Both the spikes tungsten and regular H3s'.

 

I run the JP silent captured spring system in all my AR platform rifles and carbines. They work well, it's not necessary to install the buffer retainer pin/spring on your build and you don't hear the "SPROING" in your cheek when the gun cycles.

https://www.jprifles.com/1.4.7.2_os.php

 

If you could post your Mid-Length barrels gas port size, ( and barrel length ) that would help with suggestions.

Or at least the specific brand barrel. ( link )