16" Midlength BCM: Which Buffer?

[Plinkin' Logs]

Okay so I got my new build together, 16" BCM Midlength Cold hammer forged 1:7 upper, Anderson lower (pre-SB281) CMMG lower parts kit and stock, Ares Armor Milspec Buffer tube. Only one last thing to settle on.

Buffers...Which buffer should I get for the 16" Midlength. I know that some people say standard carbine, some say H buffer, some even say H2s or T2s. I want to be able to shoot the lightest loads but also want to mitigate as much recoil as possible for rapid fire drills.

What do you guys run in your Middies?

 

[C-grunt]

H2 should work well.

 

[Jackal]

H or H2. For a defensive rifle, I'd always lean towards a slightly lighter one.

 

[briansmithwins]

I've got that exact upper and it works pretty much perfectly* with a standard buffer. Recoil is minimal.

BSW

*Light loads like Wolf in colder weather occasionally short stroke. But that happens with multiple rifles.

 

[Inebriated]

Mine came with an H buffer. It works fine with Wolf. I'm shooting a lot less Wolf in place of XM855 though, so I'm considering upping it to an H2. Have to test it, regardless of what you pick.

 

[Gordon]

Spikes heavy buffer in all my middies and they are smooth and work great.
http://www.bravocompanyusa.com/ST-T2-Heavy-Buffer-by-Spikes-Tactical-p/st-t2.htm

 

[9mmepiphany]

I'm running the standard carbine buffer with my BCM upper...I got the 16" mid-length with the KeyMod handguards...has run well in competition and through a couple of 3-day training classes; even shooting pretty light PMP 5.56x45mm

 

[NWcityguy2]

There isn't going to be a night and day difference between a step up or down in buffer weight. If your lower comes with a carbine or H buffer, go ahead and start with that. If the gun doesn't feel jumpy, with the carrier having too much velocity left over at the end of its travel, you're probably going to be just fine.

If you decide to buy a heavier buffer, go ahead and buy an H3. With that you can use the individual weights to make an H or H2.

 

[Tomac]

I own 3 BCM 16" LW middys w/the Mod 0 comp. All have std buffer springs and H3 buffers. All run 100% and will lock back on 55gr PMC Bronze (weakest ammo I've tested them with), even my training rifle w/over 1,200rds through it w/o cleaning.
There is some personal preference involved w/regard to recoil impulse so some experimentation may be in order.
HTH...
Tomac

 

[Welding Rod]

I have four of those BCM mid-length uppers and I run standard carbine buffers in all of them, never had a problem.

 

[minutemen1776]

I have a BCM middy upper. I've run a standard buffer, a heavy buffer, and a Spike's ST-T2. The Spike's is noticeably smoother, so that's what I use now.

 

[wally]

Never a problem for me with the standard buffer in a 5.56/.223. I save the heavier buffers for the guns I mostly shoot suppressed or the SBRs.

 

[dvdcrr]

Carbine.

 

[Quentin]

H buffers in my 16" midlengths (one BCM).

 

[Hardtarget]

Is there a chart that shows the buffer designation and weight...light to heavy...so I could see how these relate to each other. This could help deciding how to correct problems when they show up...if they start.

Not trying to hijack this. I do not know how these line up weight wise.
Thanks.

Mark

 

[9mmepiphany]

Is there a chart that shows the buffer designation and weight...light to heavy...so I could see how these relate to each other.

[resize=400] [/resize]

The rule of thumb is to use the heaviest buffer that will cycle your weakest ammo

 

[Tomac]

Great chart but it left out the H3 buffer which has 3 tungsten weights and weighs 5.4oz.
Tomac

 

[Fishbed77]

The H2 or ST-T2 buffers run like a charm in my 16" BCM upper.

 

[Hardtarget]

Thank you 9MM. That is the very chart I needed. Just never saw that. I must have been under a log somewhere!

Mark

 

[9mmepiphany]

You're welcome.

Interestingly, the owner of AR15 Barrels.com is a member on this forum

 

[Plinkin' Logs]

The only thing different is the Spikes T1 and T2 use tungsten powder as opposed to weights. Some people say this actually inhibits reciprocal return force of the spring compared to the free moving solid weights. Some people prefer it.

 

[Gordon]

Yup about the Spikes buffers. I use the T1 on middies and the T2 on carbine length and like the action!

 

[MistWolf]

...What do you guys run in your Middies?

I would suggest the BCM 8 position version of the VLTOR A5 receiver extension and the A5 buffer that is closet in weight to the rifle buffer along with a standard rifle spring. The unmarked A5 buffer I have weighs an actual 5.45 oz on my scale. The A5 receiver extension assembly is smoother than the carbine RE assembly and at least as reliable as the rifle RE assembly.

If you decide to use the carbine RE assembly, the H buffer (3.75 oz actual weight on my scale) is really the lightest you should start with. I don't have a carbine buffer to throw on the scale but it's really too light for a 16 inch middy with the right sized gas port.

Sometimes, we get so wrapped up in tuning our ARs for the softest recoil possible, we forget that a little "over gassing" is actually a good thing for a reliable extraction under adverse conditions. A little bit of over gassing, not a lot.

The AR depends on three things for reliable functioning under a wide variety of condidtions- Reciprocating mass, spring rate and gas. If you change any one of those three things, you have to adjust the other two to match. You have to have not only enough momentum for the rifle to feed reliably, but the right kind. The momentum has to have the right amount of mass and the right amount of speed for reliable feeding. Get too far outside the norm of the three legs of mass, spring rate & gas and you'll have a picky rifle