A-5 Buffer setup 308 help

[Yeti-george]

Is swapping out a carbine buffer setup on a midlength dpms 308 for a a5 buffer setup worth it. What spring/ buffer combo should be used.

 

[hlee]

What are the perceived advantages of the A5 system?

 

[6.5SH]

Is swapping out a carbine buffer setup on a midlength dpms 308 for a a5 buffer setup worth it. What spring/ buffer combo should be used.

The actual A5 length buffer will not work in an AR10. If your buffer is the standard AR15 carbine length you are already using the A5 length receiver extension, it is where they originated. If you have the extra short buffer, you are using a standard length carbine receiver extension.

With the different lengths and profiles of large frame bolt carriers there is not a lot of easy mix and match here, stick with the profiles the OEM shipped it with.

This is a major pain point for franken-gun AR10 builds as there are so many conflicting standards.

 

[Yeti-george]

What are the perceived advantages of the A5 system?

Less felt recoil. Softer recoil.

 

[Cascade Hemi]

The actual A5 length buffer will not work in an AR10. If your buffer is the standard AR15 carbine length you are already using the A5 length receiver extension, it is where they originated. If you have the extra short buffer, you are using a standard length carbine receiver extension.

With the different lengths and profiles of large frame bolt carriers there is not a lot of easy mix and match here, stick with the profiles the OEM shipped it with.

This is a major pain point for franken-gun AR10 builds as there are so many conflicting standards.

What he said. "A5" is the buffer, not the receiver extension.

 

[JR1200W3]

Less felt recoil. Softer recoil.

Then JP SCS which does fit LFAR platforms. Pair with a JP LoMass BCG and tune the gas along with the adjustable buffer weights and springs to get the lowest reciprocating weight that will still run the gun reliably. It's not a complicated process and results in the lowest recoil/ shortest recoil cycle I've felt on a 308W gas gun.

 

[LRRPF52]

Is swapping out a carbine buffer setup on a midlength dpms 308 for a a5 buffer setup worth it. What spring/ buffer combo should be used.

You will not be using an A5 buffer with a large frame DPMS in an A5/ArmaLite RET, but the A5 RET is what you want.

The ArmaLite/A5 RET is great for the large frame carbines because you can use a longer AR-10 spring and the common AR-15 carbine length buffers, vs the tiny little DPMS LR-308 carbine buffers that kinda suck.

The biggest problem with using a standard AR-15 carbine RET with a large frame AR is that they don’t allow enough spring length to fit in there. The A5 RET allows a full-length extra power AR-10 rifle spring, so when you pair that with an AR-15 carbine buffer, the guns run like they’re supposed to.

ArmaLite Inc. was probably the first company to crack the code of reliability with an AR-10 carbine in the 2000s. KAC had a lot of problems with the early SR-25K and MLGS 16” SR-25s using standard AR-15 carbine RETs. They went to mid-length RETs and longer action springs quite some time ago.

 

[Yeti-george]

The actual A5 length buffer will not work in an AR10. If your buffer is the standard AR15 carbine length you are already using the A5 length receiver extension, it is where they originated. If you have the extra short buffer, you are using a standard length carbine receiver extension.

With the different lengths and profiles of large frame bolt carriers there is not a lot of easy mix and match here, stick with the profiles the OEM shipped it with.

This is a major pain point for franken-gun AR10 builds as there are so many conflicting standards.

Then JP SCS which does fit LFAR platforms. Pair with a JP LoMass BCG and tune the gas along with the adjustable buffer weights and springs to get the lowest reciprocating weight that will still run the gun reliably. It's not a complicated process and results in the lowest recoil/ shortest recoil cycle I've felt on a 308W gas gun.

I don't want a oil filled tube In my gun with proprietary aparts

 

[db2000]

I just changed to a heavier buffer. Helped the recoil some but I don’t feel like it’s a night and day difference.
A2 rifle tube, Tubbs AR10 flat spring, KAK 9.3oz AR-308 buffer, Superlative AGB.

 

[JR1200W3]

I don't want a oil filled tube In my gun with proprietary aparts

It's not filled with oil. I don't think you know what it is. And there's nothing more proprietary than a VLTOT A5 buffer tube and buffers.

 

[BCP]

Less felt recoil. Softer recoil.

It'll help a little bit especially if you add an adjustable gas block and a muzzle brake

What model rifle do you have exactly and do you handload?

 

[LRRPF52]

The spring length/weight is more important than the buffer weight.

Buffer weight is really to counter carrier bounce in full auto guns.

Port diameter and spring weight really are the main places to tame the system into an optimum cyclic rate window.

 

[loclass]

I've found the Tubbs flat wire spring combined with a Kynshot hydraulic buffer provides a very soft recoil impulse. This is in an A5 length receiver extension tube. I don't recall which model buffer I used. I've used the hydraulic buffer for 2500+ rounds without any issues.

 

[MK20]

Then JP SCS which does fit LFAR platforms. Pair with a JP LoMass BCG and tune the gas along with the adjustable buffer weights and springs to get the lowest reciprocating weight that will still run the gun reliably. It's not a complicated process and results in the lowest recoil/ shortest recoil cycle I've felt on a 308W gas gun.

Yeah, don't do this if you want reliability. You will have headache after headache. Just get the Armalite AR10 RET kit with the tube, spring, buffer, and castle nut from everygunpart.com and then use the heaviest buffer that you can that gives you 3 o'clock ejection.

 

[LRRPF52]

I've found the Tubbs flat wire spring combined with a Kynshot hydraulic buffer provides a very soft recoil impulse. This is in an A5 length receiver extension tube. I don't recall which model buffer I used. I've used the hydraulic buffer for 2500+ rounds without any issues.

Have you shot that set-up both in the extreme cold and summer?

One of the challenges with hydraulic fluid cylinders and temperature gradients is loss of the seals from cycles in varying temp and pressure environments. They work amazingly-well with such a smooth feel to the action, until they fail.

2500rds is a good run though. I hope it continues to work for you for another 2500rds.

They have always interested me.

 

[JR1200W3]

Yeah, don't do this if you want reliability. You will have headache after headache. Just get the Armalite AR10 RET kit with the tube, spring, buffer, and castle nut from everygunpart.com and then use the heaviest buffer that you can that gives you 3 o'clock ejection.

I have two LFARs that use this setup with no problems. Both are 100% reliable. Mixing and matching parts in the LFAR is where you run into trouble on these platforms, which is what you're suggesting

 

[Cascade Hemi]

Buffers and springs are really over thought.

 

[loclass]

Have you shot that set-up both in the extreme cold and summer?

One of the challenges with hydraulic fluid cylinders and temperature gradients is loss of the seals from cycles in varying temp and pressure environments. They work amazingly-well with such a smooth feel to the action, until they fail.

2500rds is a good run though. I hope it continues to work for you for another 2500rds.

They have always interested me.

I've not used it in extreme cold. I'd say it's been run between 40 and 90F. It's in a gas gun I use for prs.

 

[tucaz]

I've found the Tubbs flat wire spring combined with a Kynshot hydraulic buffer provides a very soft recoil impulse. This is in an A5 length receiver extension tube. I don't recall which model buffer I used. I've used the hydraulic buffer for 2500+ rounds without any issues.

kynshot must have got their shit together then. back when they started those where junk. had 2 of them in 5.56 cal destroy themselves inside of 500 rounds.

why did endine stop selling their hydraulic buffers? i know they came from .mil and those work great, i still have one that keeps going.

endine makes smaller versions for manufacturing equipment for things that reciprocate. i have them on some small printing machines. they last for ever.

 

[tucaz]

Have you shot that set-up both in the extreme cold and summer?

One of the challenges with hydraulic fluid cylinders and temperature gradients is loss of the seals from cycles in varying temp and pressure environments. They work amazingly-well with such a smooth feel to the action, until they fail.

2500rds is a good run though. I hope it continues to work for you for another 2500rds.

They have always interested me.

i have an original endine hydraulic buffer and have not seen any issues regarding temps hot or cold but i live in s. az. its been shot plenty in the heat.

 

[LRRPF52]

i have an original endine hydraulic buffer and have not seen any issues regarding temps hot or cold but i live in s. az. its been shot plenty in the heat.

Th heat is great for seals as long as you stay within a pretty narrow temperature range (flatland AZ).

Once you start cycling through a wide temp range, things shrink all around, including seals. Add the normal cylinder pressure and the fluid often finds a way to get out.

There are som cool Aerospace solutions to that though, but they’re expensive (cryogenic cooling pre-fitment).

 

[JR1200W3]

Just dropped a JP LoMass BCG and H2 SCS into a new to me Seekins SP10M builders kit with a 6.5CM Proof barrel today. Salvaged a used SLR 8 gas block I had laying around. Took it out this afternoon to zero and function check. Fired 40rds of reloads I had laying around. 43.8gr of StaBall under a 140 Nosler BTHP going 2757fps. I didn't even bother adjusting the gas and fired 40 rounds without a single hiccup, locking back on a mag. Suppressed and no marks on the rim or casehead. Proof + JP BCGs + SCS = smooth shooting large frame success every time.

 

[Ronws]

You will not be using an A5 buffer with a large frame DPMS in an A5/ArmaLite RET, but the A5 RET is what you want.

The ArmaLite/A5 RET is great for the large frame carbines because you can use a longer AR-10 spring and the common AR-15 carbine length buffers, vs the tiny little DPMS LR-308 carbine buffers that kinda suck.

The biggest problem with using a standard AR-15 carbine RET with a large frame AR is that they don’t allow enough spring length to fit in there. The A5 RET allows a full-length extra power AR-10 rifle spring, so when you pair that with an AR-15 carbine buffer, the guns run like they’re supposed to.

ArmaLite Inc. was probably the first company to crack the code of reliability with an AR-10 carbine in the 2000s. KAC had a lot of problems with the early SR-25K and MLGS 16” SR-25s using standard AR-15 carbine RETs. They went to mid-length RETs and longer action springs quite some time ago.

That is so funny because Stoner originally wanted to build AR-10s for the Army back in the day but they went with KAC in spite of problems.

Anyway, @Yeti-george , listen to these guys.

I don't have much experience to offer but my own. I have the Windham Weaponry R16SFST-308.

This has a 4150M chromed moly barrel with a fixed mid-length gas tube. I never fired it in this original carabine config. I switched to a rifle tube and the Magpul PRS Gen III adujustable stock. Long story short, I had to mix and match weights in my buffer and got up to 6.1 ounces to run it right with 168 gr HPBT.

I am still the stupidest person here but I know just enough to know the other guys are giving you good advice.