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Discussion Starter · #1 ·
I noticed that that a buffer I picked up locally from a guy (that builds and sells a lot of .223)rifles is very heavy.
It is about 4 3/4 ounces which I assume is an H-2 buffer.
Everything I have read says that there should be 3 weights in the buffer bit I took the pin out and there were
only 2 steel weights in it.
Is this normal ?
Just the buffer without any weights in it weighs a smidge over 2 1/2 ounces.The tube is made of steel.

I was function testing my build consisting or Aero Precision Gen II lower and 6.8ARP 18 inch mid weight melanited barrel and shooting Hornady 120 SST factory loads and the heavy buffer.
The combo was ejecting at about 4:30 with slightly frosted cases.
Am I correct in thinking that Maybe with the heavier buffer that pressure is building higher before ejection because the case walls are sticking to the chamber walls and contributing to
the cases being slightly frosted ??

Would using a lighter weight buffer bring the case ejection closer to the 3 oclock position ??

Is it Ok to use the buffer reassembled with no weights in it(again it weighs a little over 2 1/2 ounces without weights) ??

If the buffer proves to be too light what could I ad inside the buffer to bring the weight to about 3 ounces??
 

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Is this a fixed stock, A2 tube? A carbine buffer will have three weights. A standard carbine buffer has three steel weights, an H buffer has one tungsten weight and two steel weights. An H2 has two tungsten and one steel. An H3 has three tungsten. If your buffer only has two weights then someone has been playing with it. A standard carbine buffer weighs 3 oz.
 

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I noticed that that a buffer I picked up locally from a guy (that builds and sells a lot of .223)rifles is very heavy.
It is about 4 3/4 ounces which I assume is an H-2 buffer.
Everything I have read says that there should be 3 weights in the buffer bit I took the pin out and there were
only 2 steel weights in it.
Is this normal ?
Just the buffer without any weights in it weighs a smidge over 2 1/2 ounces.The tube is made of steel.

I was function testing my build consisting or Aero Precision Gen II lower and 6.8ARP 18 inch mid weight melanited barrel and shooting Hornady 120 SST factory loads and the heavy buffer.
The combo was ejecting at about 4:30 with slightly frosted cases.
Am I correct in thinking that Maybe with the heavier buffer that pressure is building higher before ejection because the case walls are sticking to the chamber walls and contributing to
the cases being slightly frosted ??

Would using a lighter weight buffer bring the case ejection closer to the 3 oclock position ??

Is it Ok to use the buffer reassembled with no weights in it(again it weighs a little over 2 1/2 ounces without weights) ??

If the buffer proves to be too light what could I ad inside the buffer to bring the weight to about 3 ounces??
Typically a heavier buffer will slow things down which would allow more time for the pressure to come down.
If you have frosting cases I would consider an adjustable gas block for that part of it.
Theres nothing wrong with 4:30 ejection if the rifle is functioning properly.
A lighter buffer will bring the ejection forward towards 3 oclock.
Heres an explanation of how buffers are supposed to be built.
http://thearguys.com/ar-facts/difference-ar-15-buffers/
However I have seen 2 or even one solid weight in cheap buffers.
I have seen 1 weight 3.0oz buffers and 1 weight 5.6oz buffers.

In my 6.8s I either run a standard 3.0oz or a 3.7oz H buffer.
I run the 3.7oz H buffer in the Triad because I am pushing 130 and 140 grain bullets and they build more pressure. That and an adjustable block dialed it in nicely.
Keep in mind the way Harrison drills his gas ports he recommends a 3.0oz standard buffer.

Dont run a buffer lighter than 3.0oz with a standard BCG as it will cycle to fast and you will be ejecting before the pressure comes down even worse.

Heres a bit more on it.
http://alamotacticalreviews.com/2014/04/04/choosing-the-proper-buffer-weight-for-the-ar-15/
 

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Discussion Starter · #4 ·
re

Is this a fixed stock, A2 tube? A carbine buffer will have three weights. A standard carbine buffer has three steel weights, an H buffer has one tungsten weight and two steel weights. An H2 has two tungsten and one steel. An H3 has three tungsten. If your buffer only has two weights then someone has been playing with it. A standard carbine buffer weighs 3 oz.
Standard Mil spec tube no extension Using a Rogers superstock on one lower
the other Lower is a fixed stock,http://gwacsarmory.com/

The buffer was untouched when I got it,brand new

 

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Discussion Starter · #6 ·
Re

Thanks Guys for the info and links.

I Imagine that it is just a cheap buffer then.

Wonder what I could put in it to get it up to 3 ounces?
 

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Awhile back during one of the shortages I built a few 5.56 uppers with barrels that ,while accurate, were horribly overgassed. Instead of trying to find a scarce, expensive adjustable GB, I stripped the buffers and poured them full of lead, leaving just enough room to replace the bumper. Wound up with a cheap H2 buffer that moved ejection from 1 to 2:30. Hillbilly engineering. RT
 

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Buffer springs and buffer weights are just tools to play around with to get what you want. Most of my ARs have adjustable gas blocks or adjustable carrier keys, but I do have some with no adjustable gas system. So I start with the "stock" spring usually 26 coils with carbine and 29 coils rifle.

Many of my ARs use zero weight, just the shell and bumper. So in carbine length they are about one ounce, then I can put one, two or three aluminum weights. I have a bag with about 30 steel weights and another 10 of tungsten.

For instance when I took my latest build a 223 Wylde 5R 20 inch fluted barrel to the range I started with a 3 ounce carbine buffer and carbine spring. But I took a one ounce, a two ounce, and a 4.6 ounce buffer with me. It was ejecting at 4:30 so I put the two ounce buffer in and it was perfect 3 to 3:30 ejection.

I also took another 6.8 upper with me, a 16 inch ARP scout. It cycled good with 90 grain Gold Dots, but was super accurate with the 110 S&B plastic tipped, as in half MOA. As Harrison states "his barrels are not Match Grade barrels" and I always add but they shoot like it!!!!!

I have Vltor A5 buffers between 2 ounces up to 7 ounces, AR15 rifle buffers from 1.5 ounces to almost 9.5 ounces (all tungsten), and then AR10 rifle buffers between 1.3 ounces to 6 ounces. AR10 (AR308) buffers only have two weights so you are limited between 1 ounce to 3.8 ounces.

It is important to remember that great functioning is more important than "perfect ejection". With adjustable gas systems I often get the best accuracy with ejection between 2:30 to 3:00.
 

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I know trial and error is what everyone is suggesting for buffer/spring combinations that are "ideal" but I am wrapping up my very first 6.8 setup and am wondering where to start.

I know everyone likes the A5 system, but the UBR2 keeps getting delayed and I don't feel like waiting so am just going to go with the normal UBR. Besides, I think that system is overhyped and you can get the same results with a stronger spring/heavier buffer anyway.

16" Midlength with carbine tube and I'm looking to load as heavy as possible and still be able to run stronger factory ammo. I'm thinking H3 with standard spring? I will also be shooting suppressed as I have an omega on order.
 

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I know trial and error is what everyone is suggesting for buffer/spring combinations that are "ideal" but I am wrapping up my very first 6.8 setup and am wondering where to start.

I know everyone likes the A5 system, but the UBR2 keeps getting delayed and I don't feel like waiting so am just going to go with the normal UBR. Besides, I think that system is overhyped and you can get the same results with a stronger spring/heavier buffer anyway.

16" Midlength with carbine tube and I'm looking to load as heavy as possible and still be able to run stronger factory ammo. I'm thinking H3 with standard spring? I will also be shooting suppressed as I have an omega on order.
Heavy springs and buffers are band-aids for fixing minor problems with overgassing etc. I would start with the standard carbine buffer and spring and see where your ejection is. 9 times out of 10 that is all you will need. The UBR is just a stock and has nothing to do with the buffer weight or type spring except to say you use the carbine vs rifle length.
 

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I know trial and error is what everyone is suggesting for buffer/spring combinations that are "ideal" but I am wrapping up my very first 6.8 setup and am wondering where to start.

I know everyone likes the A5 system, but the UBR2 keeps getting delayed and I don't feel like waiting so am just going to go with the normal UBR. Besides, I think that system is overhyped and you can get the same results with a stronger spring/heavier buffer anyway.

16" Midlength with carbine tube and I'm looking to load as heavy as possible and still be able to run stronger factory ammo. I'm thinking H3 with standard spring? I will also be shooting suppressed as I have an omega on order.
A standard carbine buffer and spring along with an adjustable gas block.

Heavy buffers are only needed in situations where you can't tune the gas with an adjustable gas block and in my opinion are a waste of money. I'm not saying they don't have a purpose.

If a gun is so over gassed that it needs an H3 buffer to slow the BCG down, it's still over gassed, just masked by the heavy buffer to slow the cycle.

My 2 cents.

Sent from a final firing position, the crosshairs are on you!
 

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Heavy springs and buffers are band-aids for fixing minor problems with overgassing etc. I would start with the standard carbine buffer and spring and see where your ejection is. 9 times out of 10 that is all you will need. The UBR is just a stock and has nothing to do with the buffer weight or type spring except to say you use the carbine vs rifle length.
I know its just a stock--like I said there is an a5 version coming out and I was willing to see if the hype was real (I think the same thing can be accomplished with heavier buffers/springs wihtout the longer tube/buffer) but its delayed again and I want to finish this build.

Running hot loads and suppressed will overgas anything. I guess what I'm saying is, I am going to try to build the heaviest system possible that will still work with factory loads trouble free.
 

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I know its just a stock--like I said there is an a5 version coming out and I was willing to see if the hype was real (I think the same thing can be accomplished with heavier buffers/springs wihtout the longer tube/buffer) but its delayed again and I want to finish this build.

Running hot loads and suppressed will overgas anything. I guess what I'm saying is, I am going to try to build the heaviest system possible that will still work with factory loads trouble free.
You'll find starting with a standard buffer and spring with an adjustable gas block will result in trouble free operation, because you can tune the gun to run hotter ammo with or without the suppressor.

Adjusting the gas system results in a properly tuned gun, not heavy buffers and springs.

Sent from a final firing position, the crosshairs are on you!
 

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I know its just a stock--like I said there is an a5 version coming out and I was willing to see if the hype was real (I think the same thing can be accomplished with heavier buffers/springs wihtout the longer tube/buffer) but its delayed again and I want to finish this build.

Running hot loads and suppressed will overgas anything. I guess what I'm saying is, I am going to try to build the heaviest system possible that will still work with factory loads trouble free.
OK, maybe I missed where you said you would be shooting suppressed. A good adjustable gas block doesn't cost much more than an H3 buffer and heavy spring and then you can shoot hot ammo, standard ammo, shoot suppressed or unsuppressed, all with a minor adjustment. Otherwise you quite likely will have to swap buffers to get the bolt to cycle properly depending on ammo and whether suppressor is installed or not.
Also, I don't think the A5 system is all that popular with 6.8 shooters. I know a few people use them but they are way overpriced and over hyped in my opinion. The adjustable gas block is much cheaper and the proper solution. As I said before, in most instances a heavy buffer is a bandaid where the adjustable gas block is the proper solution. The heavy buffer may work but is just as likely to cause more problems that it solves. For one thing, most M4 carbines are overgassed from the start and that is what that A5 system was designed for. Not so much true with a 6.8 barrel, if you buy from the right barrel maker they size the gas port to the length of barrel and generally for a standard buffer. I know that is what ARP does.
 
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