Heavier A2 rifle buffer

[tom12.7]

That could be used possibly as a way to guide towards the solution of total reciprocating mass. A problem could arise though, as the balance of total mass and action mass can be a negative depending on carrier bounce. Generally, more action mass in the buffer reduces the issues.
I would tend to prefer an action (buffer) mass that reduces issues reasonably over the cycle of the action. In some combinations it has shown that the A5H2 with a full mass M16 carrier bounces more than a A5H4 with a reduced carrier mass for some, but it is few. There does seem to be a trend though that shows of what may be.

[dmaxfireman]

Updated weights, I had some failures to strip a new round and failures to lock back with the 6.87oz setup with American Eagle 55gr today. Ran amazing suppressed but once it got dirty and I removed the can it started to choke. Backed the weight down to 5.99oz

A5H1 - 4.55oz
A5H2 - 5.47oz
A5H3 - 6.31oz
A5H4 - 7.16oz

These include the last weight rubber end and spring from an A5 buffer

A2 with 5 steel weights and aluminum spacer - 5.18oz
A2 with 1 tungsten and 4 steel weights and aluminum spacer- 5.99oz
A2 with 7 steel weights (aluminum spacer removed) - 6.14oz
A2 with 2 tungsten and 3 steel weights and aluminum spacer- 6.87oz
A2 with 6 steel weights and 1 tungsten weight (aluminum spacer removed) - 6.98

[joedirt199]

I was working on this very same topic and puchased a short section of carbide tungsten from ebay but have to get it cut to size to test. Should make about 4 weights. Too hard to cut with hand tools so it needs to go to a machine shop for a lathe. May also cut down an aluminum spacer to the steel/tungsten size for more combinations.

[ColtSeavers]

Updated weights, I had some failures to strip a new round and failures to lock back with the 6.87oz setup with American Eagle 55gr today. Ran amazing suppressed but once it got dirty and I removed the can it started to choke. Backed the weight down to 5.99oz

A5H1 - 4.55oz
A5H2 - 5.47oz
A5H3 - 6.31oz
A5H4 - 7.16oz

These include the last weight rubber end and spring from an A5 buffer

A2 with 5 steel weights and aluminum spacer - 5.18oz
A2 with 1 tungsten and 4 steel weights and aluminum spacer- 5.99oz
A2 with 7 steel weights (aluminum spacer removed) - 6.14oz
A2 with 2 tungsten and 3 steel weights and aluminum spacer- 6.87oz
A2 with 6 steel weights and 1 tungsten weight (aluminum spacer removed) - 6.98

Thank you for taking the time to do and post this. Always nice to have more info.

[sinister]

Clint at Heavy Buffers sells an XH for an A1/A2/A4 rifle: AR15R-XH - 11 ounces.

Pricey though, due to the tungsten.

[joedirt199]

I found tungsten cut to size on rainier arms but they want $16 a weight. Cost me $20 for a 3" bar. Didn't think it would be so hard to cut but found out other wise.

[dmaxfireman]

Bumping this back to the top. Been running the 5.99oz buffer set up for the past couple years and it was working famously with the White Oak barrel. I recently swapped out the White Oak for a Douglas from Compass Lake. I was having failures to lock back about 25% of the time. I am going to switch back to a stock A2 buffer setup or switch out my A1 stock for a true A5 setup.

[Clint]

Bumping this back to the top. Been running the 5.99oz buffer set up for the past couple years and it was working famously with the White Oak barrel. I recently swapped out the White Oak for a Douglas from Compass Lake. I was having failures to lock back about 25% of the time. I am going to switch back to a stock A2 buffer setup or switch out my A1 stock for a true A5 setup.

The 6 oz buffer really isn't that heavy.

It sounds like the gas drive may be a little low.

Any idea on gas port sizes?

[tom12.7]

I agree with Clint on this. If the chamber/bore/ammunition combination delivers the proper pressure at the port location, then it should lock back with a proper total reciprocating mass, given normal porting ranges/leak down/drag/action spring/etc.. There's a few things to possibly look into, but check the basics first.

[dmaxfireman]

Measured the buffer spring, 11-9/16" but only 37 coils. Went back to the 5.99oz buffer, and going to order a new rifle spring from BCM and see if anything changes.