School me on AR buffers

[Johnny C]

So you got pistol, carbine and rifle buffers

You got mil spec, hydralulic and tungstin filled

Whats the deal?

Does anyone know a webpage that compares all of these?

Thanks,
Johnny C

 

[shooter521]

So you got pistol, carbine and rifle buffers

You got mil spec, hydralulic and tungstin filled

Whats the deal?

"Pistol" buffers are unique to pistols.

"Rifle" buffers are for rifle-length receiver extensions and fixed stocks. They come in one style/weight.

"Carbine" buffers are available in several weights (utilizing a combination of steel and/or tungsten components), the most common of which are:

CAR - 3 steel weights - 3.0 oz.
H - 1 tungsten, 2 steel weights - 3.7 to 3.8 oz.
H2 - 2 tungsten, 1 steel weights - 4.6 oz.
H3 - 3 tungsten weights - 5.4 oz.
9mm - solid - 5.5 to 5.6 oz.

Image courtesy of AR15barrels.com; reprinted with permission

There are also some proprietary setups out there, such as VLTOR's new "A5" and the Slash "Q" buffer, but they are niche products designed for specific applications.

The hydraulic and pneumatic buffers (Enidine, et al) are designed primarily for recoil reduction. They work, but their design adds additional failure points to the system, and IME they are not built to withstand harsh firing schedules. I have broken an AAC pneumatic buffer, and a friend and fellow INGOer has had an Enidine start to come apart after relatively little use.

When selecting a buffer for your carbine, the conventional wisdom is to go with the heaviest one that allows reliability when shooting the lightest ammo you intend to use (for most, this would be Wolf). I run 9mm buffers in all my guns except for my mid-lengths, which have H2s.

An acquaintance of mine has a protocol for testing buffers that involves firing single rounds to ensure bolt lockback x5, and firing loosely in one hand, sideways (both sides) and upside down for at least 20 rounds each position with no stoppages.

My

 

[esrice]

[/thread]

 

[Fastmover]

So what if you want to swap a fixed stock on a rifle length AR with a M4 type stock? What type of buffer and parts would you need?

 

[shibumiseeker]

Changing buffer weights also changes the cyclic rates, a little less of a concern for those of us with semi-auto rifles

If you start messing around with adding carbine stocks to rifle length guns or vice versa you will also need to tune the gas blocks to get proper operations. AR15s work pretty well if you stick with plug and play, but you'll need to do a little more learning to get things tuned to work together properly if you want to change it up some.

 

[vf-202]

the fast answer to what you want is the heavier the buffer the less the recoil since force = mass * acceleration
the more mass the less acceleration since force is constant

 

[jblomenberg16]

So what if you want to swap a fixed stock on a rifle length AR with a M4 type stock? What type of buffer and parts would you need?

To add a fixed rifle style stock where you already have a "carbine" style adjustable stock, you would need to get the rifle buffer & spring as well as the appropriate receiver extension (aka buffer tube) that would work with A1 or A2 style fixed rifle stocks.

To go the other way you'd need to get the appropriate carbine buffer and spring of choice, and the correct reciever extension (aka buffer tube) for the stock that you would want to run. My if you are doing a carbine style adjustable stock to go with the milspec extension (aka buffer tube).

 

[shooter521]

If you start messing around with adding carbine stocks to rifle length guns or vice versa you will also need to tune the gas blocks to get proper operations.

"tune the gas blocks"? Whatever do you mean?

I've owned guns with carbine-length gas systems with rifle buffers before, and they never needed "tuning" of any kind. Heck, the Olympic Plinker is set up that way as a factory gun, as were a crap-ton of different makes/models during the AWB years. I've also seen rifle builds with carbine buffer systems that have run just fine. In fact, the USMC is looking at an adjustable stock kit (carbine buffer) as a retrofit for their M-16A4s. If what you're saying is true, that would be tens of thousands of rifles that would need to be pulled off the line for "tuning," and I don't think the Corps would be down for that.

My

 

[Fastmover]

Ok, so to replace the A2 fixed stock on my rifle, I need to remove the stock and buffer tube and replace them both? Is that right?
I'm looking to put one of those magpul jobs on my rifle. Just want to be sure I get the right bits and pieces that will work on a rifle rather than a carbine.

 

[shooter521]

Ok, so to replace the A2 fixed stock on my rifle, I need to remove the stock and buffer tube and replace them both? Is that right?
Just want to be sure I get the right bits and pieces that will work on a rifle rather than a carbine.

So to be perfectly clear, you DO have a rifle, as in a 20" barrel or better with a full-length (~12" or so) gas tube?

In order to convert to a collapsible stock, you will need a complete collapsing stock kit (receiver extension, stock body, carbine buffer and spring, endplate and castle nut); there are no common parts between the rifle and carbine stock systems, so nothing from your old stock assembly can be reused.

When buying a carbine stock kit, note that the receiver extension can be either mil-spec or commercial-spec diameter; either is OK, but you'll want to be sure you get the appropriate stock body to match it.

With all that said, you might want to look at the VLTOR A5 setup; it is supposed to be the "new hotness" for your particular application.
EMOD A5 combo kit - Vltor Weapons Systems

HTH!

 

[Fastmover]

Shooter,
Correct I have a 20" barrel on my AR.

Thanks for the clarification and information.

 

[shooter521]

[/thread]

Not quite yet...

Here's some awesome high-speed video of different buffers in action, and an excellent treatise on the subject from the Vuurwapen blog. Honestly, it's making me re-think my general use of the 9mm buffer in 5.56mm applications. Might be investing in a couple more H2s or H3s, instead.

YouTube - AR-15 Buffer Test - High Speed Video - 1000 Frames Per Second

AR-15 Buffer Comparison – High Speed Video Vuurwapen Blog

 

[MWCMT]

I looks like the 9 mm buffers "bounce" before locking up!

 

[shooter521]

I looks like the 9 mm buffers "bounce" before locking up!

So do the regular CAR buffer and the Spike's ST-T2 heavy buffer. I didn't realize how pronounced this phenomenon (known as "bolt bounce") was with the 9mm buffer until I saw the high-speed. The H, H2 and H3 buffers, with their reciprocating weights, were designed to minimize it.

Bolt bounce isn't much of a problem in semi-auto carbines as long as they are well-maintained. As parts and springs wear, though, it can be a contributing factor in certain types of malfunctions and premature wear (which can occur even though the gun appears to be functioning just fine).

 

[in812]

Tag

 

[shibumiseeker]

"tune the gas blocks"? Whatever do you mean?

I've owned guns with carbine-length gas systems with rifle buffers before, and they never needed "tuning" of any kind. Heck, the Olympic Plinker is set up that way as a factory gun, as were a crap-ton of different makes/models during the AWB years. I've also seen rifle builds with carbine buffer systems that have run just fine. In fact, the USMC is looking at an adjustable stock kit (carbine buffer) as a retrofit for their M-16A4s. If what you're saying is true, that would be tens of thousands of rifles that would need to be pulled off the line for "tuning," and I don't think the Corps would be down for that.

My

That the AR15 can operate with a wide range of ammo and differences in gas tube lengths, buffer weights, and spring strengths is a testament to its design. But when it doesn't work reliably with a particular loading or configuration you can open or restrict the gas block. You can also adjust the gas block to change the eject pattern. I've only played with it once, slightly opening the gas block to get a rifle to reliably feed light loads I use for practice. I could have changed buffer weight or springs, but I wanted to be able to use the rifle with full power loads without having to change anything. The tradeoff is probably more erosion of the rings, but since I shoot a hundred light loads for every full power load I shoot I wasn't too worried about it. You can even buy adjustable gas blocks, though I just drilled mine out a few thousandths more.
J P ENTERPRISES : AR-15/M16 ADJUSTABLE GAS BLOCK - World's Largest Supplier of Firearm Accessories, Gun Parts and Gunsmithing Tools

 

[pierce195]

Took my SBR's to the range to test buffers today.

Before leaving I got the postal scale out and weighted the buffer. H buffer 3.8 oz's, H2 buffer 4.6 oz's, and H3 5.4 oz's.

First rifle is a Noveske 10.5 SBR now using a suppressor. The rifle has about 1000 rounds fired with an H buffer before the suppressor was added and 200 rounds with the suppressor. All 1200 rounds have been fired without issue. Rifle was fired with H2 buffer install. There was noticeable smoother recoil with the H2 buffer installed over the H buffer. Next the H3 buffer was installed. The H3 buffer had the best overall feel of the three. The recoil impulse feel smoother and I had less muzzle rise. I'm going to leave the H3 installed for a few more range trips.

Next rifle is a 14.5 BMC mid-length SBR. This rifle has less than 200 rounds fired H buffer installed. I installed the H2 and began my range session. The H2 buffer performed well and the light recoil impulse was cut down even more. The H2 was left in the gun and will being staying.

This was not a scientific test, but there is a noticeable different in the feel of the rifles with different buffers. The springs in both guns are standard carbine recoil springs. Both were installed when the SBR's were built.

 

[jblomenberg16]

Took my SBR's to the range to test buffers today.

Before leaving I got the postal scale out and weighted the buffer. H buffer 3.8 oz's, H2 buffer 4.6 oz's, and H3 5.4 oz's.

First rifle is a Noveske 10.5 SBR now using a suppressor. The rifle has about 1000 rounds fired with an H buffer before the suppressor was added and 200 rounds with the suppressor. All 1200 rounds have been fired without issue. Rifle was fired with H2 buffer install. There was noticeable smoother recoil with the H2 buffer installed over the H buffer. Next the H3 buffer was installed. The H3 buffer had the best overall feel of the three. The recoil impulse feel smoother and I had less muzzle rise. I'm going to leave the H3 installed for a few more range trips.

Next rifle is a 14.5 BMC mid-length SBR. This rifle has less than 200 rounds fired H buffer installed. I installed the H2 and began my range session. The H2 buffer performed well and the light recoil impulse was cut down even more. The H2 was left in the gun and will being staying.

This was not a scientific test, but there is a noticeable different in the feel of the rifles with different buffers. The springs in both guns are standard carbine recoil springs. Both were installed when the SBR's were built.

My 16" Carbine really likes the H2 buffer as well. Noticeable difference from the standard carbine buffer.

 

[smcgee]

New to the AR-15 platform but prior military so not new to the game. I've been researching replacing my recoil buffer and spring with a David Tubbs CS Spring and Spike ST-T2 recoil buffer tungsten powder filled. What's the veterans thoughts on these two drop in upgrades? I've been recommended pneumatic and hydrolic but have no experience at all with either and after reading I think I'm leaning towards Tubbs and Spike.

 

[mammynun]

smcgee, My opinion is that they're usually unnecessary unless you're trying to improve reliability for different types of ammo. I've never seen that problem on anything other than an SBR, unless there's an underlying issue (gas port size, gas block, etc), in which case springs and buffers may not be able to compensate for the issue anyway.

The can also be used to smooth out the recoil impulse, but I have a hard time feeling an improvement even when shooting 2 AR's side by side.