A5 buffer system?

[Rittmeister]

I'm curious what experience folks have with either the VLTOR A5 buffer system, or the newer BCM Recoil Mitigation System. I hear they are nearly the same thing and even designed by the same person. My main question is if I were to get the system for my rifle, which buffer would suit my setup best. NB - I've read a number of people who say they can't tell a difference using the A5-type parts vs. regular carbine buffer, but I'm researching right now and considering giving it a try.

My main rifle is a BCM 16", midlength-gas upper paired with BCM bolt carrier group. I currently use an H2 buffer with mil-spec silicon recoil spring. I am a cheap shooter and I use almost exclusively 55gr/M193-type ammo.

Both the A5 and the BCM recoil systems are available with several different buffer weights. I'm curious a) which A5 buffer is "equivalent" to what I've got now, and/or b) which one might genuinely reduce felt recoil somewhat.

Thanks for any info.

 

[sevt_chevelle]

All my ARs get the A5 system.
My first AR was a colt 6920 it has the typical carbine buffer.
My second AR is one I built, colt lower, every part is the same as my 6920 minus the A5 buffer.
Anyways, you swap out the lowers on that 6920 you can most definitely feel the difference.

Had a buddy of mine in attempt to confirm who is a not gun person and knows jack about ARs try both systems. He too could feel the difference.

 

[Varminterror]

My first AR was a colt 6920 it has the typical carbine buffer.

In fairness, your 6920 actually had the luxury of NOT having a “typical carbine buffer.” Conventional length, certainly, but Colt uses heavier H weight buffers, almost a full ounce heavier than “Carbine” weight buffers. So you had the same weight as a standard A5 system, just without the extra length spring arrangement of the A5. The performance and driving experience difference between a carbine buffer and A5 is even more dramatic!

 

[N555]

It's what the carbine buffer should have been form the get go.
The A5 uses an aluminum buffer body with with 4 weights.
If an A5 has all steel weights in it then it's about equal to pretty much standard carbine buffer with one tungsten aka an H or H1 buffer.
My A5 was full of tungsten, making it an H4. I wish they sold a steel body buffer.
But then I switched it up, kept the A5 tube, rifle spring, switched to a steel body 3 weight carbine buffer and hydraulic buffer stop installed in my A5 tube.
This is what I did.
https://www.thehighroad.org/index.php?threads/industrial-ar15-hydraulic-shock-buffer.904921/
Which but hurt a bunch of people, you can tell who all the ones are that over paid for some fancy buffer rig.

 

[Rittmeister]

All my ARs get the A5 system.
My first AR was a colt 6920 it has the typical carbine buffer.
My second AR is one I built, colt lower, every part is the same as my 6920 minus the A5 buffer.
Anyways, you swap out the lowers on that 6920 you can most definitely feel the difference.

Had a buddy of mine in attempt to confirm who is a not gun person and knows jack about ARs try both systems. He too could feel the difference.

In fairness, your 6920 actually had the luxury of NOT having a “typical carbine buffer.” Conventional length, certainly, but Colt uses heavier H weight buffers, almost a full ounce heavier than “Carbine” weight buffers. So you had the same weight as a standard A5 system, just without the extra length spring arrangement of the A5. The performance and driving experience difference between a carbine buffer and A5 is even more dramatic!

I appreciate these two posts. Can either of you tell me what specific A5 buffer weight you actually used? That's kinda what puzzles me, and at least with the BCM setup it affects the price as well.

It's what the carbine buffer should have been form the get go.
The A5 uses an aluminum buffer body with with 4 weights.
If an A5 has all steel weights in it then it's about equal to pretty much standard carbine buffer with one tungsten aka an H or H1 buffer.
My A5 was full of tungsten, making it an H4. I wish they sold a steel body buffer.
But then I switched it up, kept the A5 tube, rifle spring, switched to a steel body 3 weight carbine buffer and hydraulic buffer stop installed in my A5 tube.
This is what I did.
https://www.thehighroad.org/index.php?threads/industrial-ar15-hydraulic-shock-buffer.904921/
Which but hurt a bunch of people, you can tell who all the ones are that over paid for some fancy buffer rig.

What's the equivalent of the "3 weight carbine buffer?" Is that an H2? I think I saw your thread about the hydraulic buffer, I found it very interesting but for now at least I want to stick with "regular" AR parts for the time being.

 

[Varminterror]

I use H2 buffers in all of my personal AR’s except ultralight go-fast competition rifles (and full weight FA carriers). The H2 conventional buffer is the same weight as an A5H1, but obviously doesn’t use a rifle spring. For A5 builds, I typically stick with that weight, A5H1 at 4.7oz.

 

[powermad]

The A5 was developed for rifle gas systems (A2) so they could use a telescoping stock.

Buffer weight depends on the gas port size no matter what action it is.
My 14.7" mid gas and 18" rifle gas use an A5 with an A5H2 buffer. Same weight as a rifle buffer with a rifle (green) spring.

This is a good list to use as a guide for gas port size and action buffer weights combo.
https://soldiersystems.net/2020/08/10/fighting-gun-101-gas-ports/

 

[N555]

2 weights is an AR10 dpms carbine buffer, most are steel body
3 weights is a standard carbine buffer, for ar15 and armalite ar10 with, uses aluminum body and all steel weights it weighs about 3oz.
4 weights are in a A5 buffer, only ever seen them in an aluminum body, with all steel weights it weighs around 4.1oz
5 weights are in a standard rifle buffer. 5.3 ounces.
*steel buffer bodies are available.
I ran a steel carbine buffer for a while. With no tungsten it weighed like 4.4oz. Ran mine full of tungsten.
Posting this reminded me that cmmg sells a stainless steel rifle buffer. I wanted to get one during the plandemic, but they were sold out and I didn't want to pay 3x normal price if I could find one. They're back in stock for like $20 over at PSA.

 

[powermad]

Vltor now has steel A5 buffers for PCC's
Up to 10 oz. A5S0 - A5S4

My AR9 used a regular A5H4 with a rifle spring, Law Folder and carbine extension.

 

[N555]

I appreciate these two posts. Can either of you tell me what specific A5 buffer weight you actually used? That's kinda what puzzles me, and at least with the BCM setup it affects the price as well.



What's the equivalent of the "3 weight carbine buffer?" Is that an H2? I think I saw your thread about the hydraulic buffer, I found it very interesting but for now at least I want to stick with "regular" AR parts for the time being.

I was using all regular AR parts aside from the hydraulic stopper. I chucked up a standard M4 buffer tube in the lathe, bored it out and cut 10x1mm threads. Installed the hydraulic stopper. People running PPC ARs have been putting a bolt or stud in the bottom of the buffer tube since forever to make up the difference between the PPC bolt and the buffer. The haters didn't like it because its better than whatever novel rube Goldberg buffer thingy they over paid for that doesn't work.
I got one of those silent buffers when they were like $80. Found it didn't work that good. Figured I could do better and I did.

 

[N555]

Vltor now has steel A5 buffers for PCC's
Up to 10 oz. A5S0 - A5S4

My AR9 used a regular A5H4 with a rifle spring, Law Folder and carbine extension.

This is news to me.
It makes sense.

 

[C-grunt]

I have an A5 on one of my ARs. Does it make a difference over a standard Colt 6920, yes. But I dont feel that it was that much of a difference. The rifle I have it on started life as a 6920 and I have another 6920 to compare it against.

If I was building another rifle from the ground up it is definitely a consideration. It does do what it claims to do. But Im not spending the money switching out all my existing carbine extensions for A5s.

You should give it a try. If you are after a smoother recoil impulse you are looking at the right place.

 

[N555]

If I do any more carbine builds I'm at least using the A5 tube. The longer A5 tube setup increases the length of pull to make all standard stocks fit me better.

 

[Varminterror]

The haters didn't like it because its better than whatever novel rube Goldberg buffer thingy they over paid for that doesn't work.

This particular “hater” of YOUR Rube Goldberg design thought - and remains to think - your idea made something simple and reliable into something more prone to failure, with no actual benefit.

Well, no benefit besides the opportunity to stab yourself in the shoulder with the huge canker sore you’ve added to the rear of your tube.

 

[N555]

The hydraulic shock I use is hit about 2,100 times per day, every day for around 3 months before it wears to the point where like new performance is degraded.
When they do wear out they don't break, they just push in with little to no resistance.
These hydraulic shocks are not anything like the consumer trash we see in a lot of products.
I have taken apart intentionally destroyed these things out of curiosity and still have no idea how you are convinced they are going to break.
I already thought of "its going good come out of the tube and hit me in the shoulder".
Before I drilled out the first tube I looked up how thick they are at the base that way i would know if i needed to drill and thread or drill and use 2 nuts. Calculated worst case scenario, poor fit on chinesium 6061 it would take over a ton of force to push a 10x1mm threaded body through a piece of aluminum.
If I was that worried that the 5oz buffer was able to hit the back of the tube with any where near the amount of force it would take to fail the threads the easy fix is put a nut on the inside of the tube.......................
Worried the nut is going to come loose, that's what locktite is for, or use a nylon ringed jam nut........
Or put a stainless helicoil in the aluminum which would just about double the push through tonnage.
Or use a 12mm body shock which would have the same effect as the helicoil.

Let's assume the shock is dead and collapsed even though I have never seen one fail that way, the weights in the buffer are seized and don't move, the spring fails to slow down the buff at all because it's the wrong spring or something.
11fps is a very optimistic speed for 3oz buffer, I run a 5, so assume a 5oz buffer running faster than the fastest 3oz.
If the buffer can stop in 0.003 seconds which seems really fast that would put a 100 times the force of gravity acceleration on the buffer, hitting the dead shock with about 30lb of force. And it takes about a ton of force to push the 10x1mm threads through that much aluminum. See why I'm not worried about the shock hitting me?

Yeah I was mad too when I got got by the silent buffer people.