When to Use a Heavy Buffer...

JCV

JCV

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In what rifle configuration would you want to use a heavy buffer?
I've got a couple builds in the works, and am curious when you would want to use a heavy buffer and what effects your decision. Is it the gas system length plus the buffer tube length? Just the gas system?

The two builds are:
14.5" barrel with carbine gas system and carbine stock assembly
16" barrel with mid-length gas system and carbine stock assembly.

I'm running a 14.5" barrel myself with a mid-length gas system and a rifle stock with no issues, but may be switching over to a carbine stock assembly soon.

Any input is appreciated.
 
It really takes experimentation to see what works or doesn't work with your particular setup. For your example with the 14.5 middy, it will run fine with the standard carbine buffer, but will cycle a bit faster/harder than you may be used to with the rifle buffer. I have a similar setup and started with the carbine buffer, but after some reading and research opted to try an H1, which slows it down just a bit, and the added mass softens the recoil a bit more. It has been super reliable, so I plan to leave it permanently. A lot of guys seem to like the Spike's T2, which uses tungsten powder and is similar in weight to what I'm running. Hope this helps.
 
Thanks for the info.
I wasn't sure if there was one set-up that was more prone to needing a heavy buffer than others.
We'll shoot them first and take it from there.
 
I've got a carbine length system on a 16" barrel with a rifle buffer in a fixed A2 and it cycles really fast, I can feel the slap of the buffer in the stock. Should I get a heavier buffer? Do they make heavier buffers for rifle stocks?

I have the spacer in, it's a normal A2 stock kit and everything is installed correctly. :)
 
When I did my first assebmly and didn't necessarily understand the differences between buffer options, I ended up with a rifle length buffer and tube with a 16" barrel and carbine length gas system. Pretty much from the get-go, I had issues with the rifle not cycling properly, failures to feed properly, not locking back after the last round in a mag, etc. I changed out the buffer to a carbine buffer and all the problems went away. I've use the T2 heavy buffers from Spikes in all of my subsequent assemblies and have never experienced the issues again. I use the T2 heavy buffer in rifles with 16" mid length and carbine length gas systems.
 
I use a H buffer on my 14.5 carbine, H2 on my 10.3 carbine and a standard carbine buffer on my 16 carbine.

I would express the same sentiment as others: experiment but from what I've heard, standard carbine buffers as well as H buffers work with 14.5 middys.
 
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OCB said:
When I did my first assebmly and didn't necessarily understand the differences between buffer options, I ended up with a rifle length buffer and tube with a 16" barrel and carbine length gas system. Pretty much from the get-go, I had issues with the rifle not cycling properly, failures to feed properly, not locking back after the last round in a mag, etc. I changed out the buffer to a carbine buffer and all the problems went away. I've use the T2 heavy buffers from Spikes in all of my subsequent assemblies and have never experienced the issues again. I use the T2 heavy buffer in rifles with 16" mid length and carbine length gas systems.
Click to expand...

So, you're saying on my 16" carbine that has an A2, I should just replace the buffer with a carbine buffer? It's got a rifle length spring, rifle length extension.

If this setup didn't work correctly, what did people do during the federal AWB? I thought carbine length gas with rifle buffer/a2 stock was the norm then?
 
wolfenkraft said:
So, you're saying on my 16" carbine that has an A2, I should just replace the buffer with a carbine buffer? It's got a rifle length spring, rifle length extension.

If this setup didn't work correctly, what did people do during the federal AWB? I thought carbine length gas with rifle buffer/a2 stock was the norm then?
Click to expand...

When you fire the gun, you should be able to clearly tell if the buffer is too light. It will have a distinct *thunk* at full bolt open (before the bolt switches direction and chambers the next round) and recoil will feel snappy in two distinct moments 1) when the buffer fully compresses the spring and hits the end of the buffer on the end of the buffer tube and 2) when the bolt closes.

If you're not getting failure to feeds at all (meaning bolt is full traveling and reliably pulling a round), throw one in and try it. If it's too heavy using light load ammo (like PMC or Tula) will result in failure to feed and failure to lock the bolt back.
 
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wolfenkraft said:
So, you're saying on my 16" carbine that has an A2, I should just replace the buffer with a carbine buffer? It's got a rifle length spring, rifle length extension.

If this setup didn't work correctly, what did people do during the federal AWB? I thought carbine length gas with rifle buffer/a2 stock was the norm then?
Click to expand...

No. A carbine buffer will not work in a rifle receiver extension. I don't recall the exact weights, but a standard carbine buffer is the lightest, then heavy, h2, h3, then rifle.

Problems arise when barrel manufacturers make the gas ports the wrong size, resulting in an over or under based gun.

Many threads on NES about this
 
Here's your simple guideline:

1) Rifle does not reliably chamber the next round or even fails to extract the previous round -> lower the buffer weight

2) Rifle does reliably chamber round -> try next higher buffer weight

The main reason to change a buffer to a heavier one on a rifle that does currently chamber the next round is to reduce the felt recoil and make follow up shots smoother.

Not locking back (bolt open) on an empty mag can sometimes be related to a buffer that is too light, but the gun would still reliably chamber the next round everytime.

Whatever you do, test it with multiple types of ammo. As in any kind you would normally buy. Just because it works nice with AE XM193 doesn't mean it will necessarily work with Tulammo 55gr. I like my rifles to run any ammo so I make sure I don't go too heavy.
 
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I do notice a big difference in the felt recoil when using tula/wolf in my rifle. I've got a spike's tactical 16" upper with a carbine length gas system with a full A2 stock with the rifle buffer/extension/spring. When firing brass/real 5.56 I notice a lot of felt recoil and I feel the thunk in the back of the stock from the buffer.

Does that mean I should get a heavier spring? I'm a little confused then. My rifle reliably cycles and shoots great, but I am worried about the thunk and it does seem over gassed.
 
wolfenkraft said:
I do notice a big difference in the felt recoil when using tula/wolf in my rifle. I've got a spike's tactical 16" upper with a carbine length gas system with a full A2 stock with the rifle buffer/extension/spring. When firing brass/real 5.56 I notice a lot of felt recoil and I feel the thunk in the back of the stock from the buffer.

Does that mean I should get a heavier spring? I'm a little confused then. My rifle reliably cycles and shoots great, but I am worried about the thunk and it does seem over gassed.
Click to expand...

Keep in mind there a huge difference in the amount of force exerted on the action between a Tulammo ~2700fps .223 round and a ~3100fps 5.56 round like XM193. So you're experience of the recoil being different is normal.

The best buffer is the heaviest one your rifle can use to still 100% reliably cycle and lock back on empty mag using the slower Tula/wolf ammo. I wouldn't change the spring, start with the buffer weight.
 
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Do they make heavier rifle buffers then? I keep hearing that recoil in an AR shouldn't be bad at all, and my other two .223/5.56 (tavor and sig 556) rifles have noticeably less than my AR. I wonder if mine is over-gassed and that's the issue?
 
BCM sells all sorts of buffers in differing weights. Start with H2 and work from there. My Colt 6920 has an H buffer in a 16" barrel.
 
wolfenkraft said:
The different weights are only for carbine though, and you can't use a carbine buffer in a rifle extension, right?
Click to expand...

You could run a carbine set up in a rifle tube with a spacer, and many do. (Carbine spring, carbine buffer, and spacer)

If you were to only change the buffer and run a rifle spring with no spacer you risk over stroking the bolt and running the back of the gas key into the extension tube.
 
icyclefar said:
You could run a carbine set up in a rifle tube with a spacer, and many do. (Carbine spring, carbine buffer, and spacer)

If you were to only change the buffer and run a rifle spring with no spacer you risk over stroking the bolt and running the back of the gas key into the extension tube.
Click to expand...


I think I found one on Brownells: http://www.brownells.com/rifle-part...rdware/ar-15-m16-buffer-spacer-prod44889.aspx

Is there a chance my rifle spring is just shot or something?
 
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I would run a buffer and spring that is reliable and allows for the fastest most accurate follow up shot. Adding more reciprocating weight is usually not the answer
 
Tweaking buffer weight usually has the biggest benefit in full auto applications for adjusting cyclic rate to achieve reliability.


Sent from my iPhone using Tapatalk
 
What rifle do you have? Most modern 16" black rifles use a carbine length tube. The rifle length tube is almost exclusively used on 18 & 20" rifles.

I would start with the buffer, I seriously doubt you need to change the tube or use a spacer.


EDIT: Just re-read the op & you contradict yourself. Either it's carbine or rifle but not both.
 
bigblue said:
What rifle do you have? Most modern 16" black rifles use a carbine length tube. The rifle length tube is almost exclusively used on 18 & 20" rifles.

I would start with the buffer, I seriously doubt you need to change the tube or use a spacer.


EDIT: Just re-read the op & you contradict yourself. Either it's carbine or rifle but not both.
Click to expand...

I'm guessing he's using an A2 stock, which uses a full length tube with a rifle buffer.
 
bigblue said:
What rifle do you have? Most modern 16" black rifles use a carbine length tube. The rifle length tube is almost exclusively used on 18 & 20" rifles.

I would start with the buffer, I seriously doubt you need to change the tube or use a spacer.


EDIT: Just re-read the op & you contradict yourself. Either it's carbine or rifle but not both.
Click to expand...

My OP? Or the other guy?

I may have misspoke but my personal rifle is a 14.5" barrel with am midlength system. I am using a fixed ACE Skeleton stock which uses a rifle length extension and buffer. I recently bought a carbine stock and carbine buffer assembly and will be installing those next week. I don't think I should have any issues with a regular buffer.

My main questions were for 2 rifles that are in the works:
16" barrel - mid-length gas system - carbine buffer assembly
14.5" barrel - carbine gas system - carbine buffer assembly

I was trying to gauge thoughts on whether or not any of the above mentioned set-ups would need or possibly need a heavy buffer.
 
The ideal answer is you will be fine. The real life answer is it completely depends on the gas port size and alignment. The amount of gas reaching the BCG is what dictates proper operation with the stock buffer and spring that are in spec.
 
josh2600 said:
If not a shtf gun, consider a low mass bcg and adjustable gas block. If you're looking for recoil reduction etc. anyways.
Click to expand...

not worried about recoil at all, just proper cycling which i will find out once everything is assembled.
 

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