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Ar10 feeding issues

L

lancegastrong

Vendimus Mortem
Minuteman
Jan 2, 2019
34
31
I have a AR-10 that I parted out and built
Stag upper
V seven BCG
Proof barrel
Lmt lower
RE5F buffer tube
A5H3 buffer (6.08 oz)
Vltor spring A5
Rifle cycles and locks back on last round

But I’m having trouble when trying to use the bolt catch. Seems like bolt doesn’t travel far enough back that I have to use the CH and it seems like the bolt covers the first round. And then first round struggles to go into battery. I’m using lancer mags and when I’m shooting hand loads or fgmm
 
I've always needed to use the CH on any AR platform to manipulate the bolt to full lock. Am I missing something here?
Possible too long a buffer/spring combo for the internal length of the receiver extension/buffer tube.
Is the charging handle hitting a cheek riser on the stock? I pulled a stupid and had this happen once.
 
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So if I pull the CH on an empty mag it locks back as well as if I was shooting. When bolt is locked back position, when seeding a new magazine and trying to use bolt release bolt doesn’t have enough travel to pick up the first round (bolt head covering maybe a 1/10 of a inch). So I have to use the CH to seed first round and usually gets stuck about half way and I have to manipulate the bolt until it goes into battery. According to Vltor A5 buffer and Spring need to be used to be “compatible”. If I were just to change out buffer to a “shorty” you think it will work?
 
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So when shooting, it feeds normal, no issues and locks to the rear? But when you try to lock it back with the charging handle, it doesn't go back far enough? Is the bolt catch engaging on the carrier or bolt face after going dry? When locking back manually?
 
lancegastrong said:
So if I pull the CH on an empty mag it locks back as well as if I was shooting. It has a PRSLite. According to Vltor A5 buffer and Spring need to be used to be “compatible”. If I were just to change out buffer to a “shorty” you think it will work?
Click to expand...
Had to edit my post due to lack of coffee. Is your charging handle hitting the cheek riser?
 
Ok, so the bolt is only partially (98%) locking back on last round, but isn't locking back fully and the bolt still protrudes out over the rear of the magazine. Then you pull the charging handle and it locks back with the bolt rotated correctly into the BCG? If that's the case, the bolt catch isn't locking back on the bolt face, it's catching on the BCG, giving the false/improper lock back. Since you can pull it further back to proper lock back, there is sufficient room in the buffer tube and the culprit of the problem is the buffer weight, or the gas delivery is insufficient. Considering your rather beefy buffer weight and spring combo I would lighten the buffer first. (Go A5H2 5.33oz)
 
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FredHammer said:
Ok, so the bolt is only partially (98%) locking back on last round, but isn't locking back fully and the bolt still protrudes out over the rear of the magazine. Then you pull the charging handle and it locks back with the bolt rotated correctly into the BCG? If that's the case, the bolt catch isn't locking back on the bolt face, it's catching on the BCG, giving the false/improper lock back. Since you can pull it further back to proper lock back, there is sufficient room in the buffer tube and the culprit of the problem is the buffer weight, or the gas delivery is insufficient. Considering your rather beefy buffer weight and spring combo I would lighten the buffer first.
Click to expand...
Okay what do you consider using I’m shooting suppressed 95% of the time
 
I thought if you're using the A5-length buffer tube for an AR-10 build, then you have to use the standard AR-15-length carbine buffers, i.e. 3.25" OAL.
 
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I’ll probably just rule it both out and get a 5.3 oz buffer at carbine length and call it a call
 
Also, the spring is technically wrong for the correct buffer. It might function, but would not be recommended.
 
lancegastrong said:
What is the recommended spring?
Click to expand...
Generally, an AR-10/308 rifle length spring works, but there are exceptions. KAC and LMT use the action system that we're talking about, and have different springs for their large frame rifle length and carbine actions. The most common spring used is an ArmaLite #EA1095, which they use for both rifle and carbine AR-10 actions.
 
msgriff said:
Probably catching the carrier and not the bolt.
Click to expand...
Exactly. I said it with more words!
“If that's the case, the bolt catch isn't locking back on the bolt face, it's catching on the BCG, giving the false/improper lock back. Since you can pull it further back to proper lock back, there is sufficient room in the buffer tube and the culprit of the problem is the buffer weight, or the gas delivery is insufficient.”
 
msgriff said:
For an AR-!0/308 using an intermediate (A5) length receiver extension, the correct length buffer is an AR-15 carbine (3.25" long).
Click to expand...
This... a Vltor A5 / Armalite pattern carbine length buffer tube, when used with a LFAR, requires a 3.25" buffer length.
 
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Ever since Vltor started marketing the AR308 receiver extension as "A5" for AR15 use, people started calling the 7 3/4" RE "A5". From a parts continuity standpoint, the longer Vltor buffer is the only part that is "A5". The SR25 had the longer carbine RE more than 15 years before Vltor thought about putting it in an AR-15.
 
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lancegastrong said:
It’s a A5 length tube which they say you should run a A5 buffer
Click to expand...
On an AR15 not AR10 … you need to use a regular AR15 buffer when using an A5 extension with an AR10 platform. Your AR10 BCG is longer than your typical AR15 BCG … thus you need a regular AR15 length buffer … go with an H3 …

Another example people mismatching buffer setups on AR10s, which is an easy thing to do.
 
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thehun said:
On an AR15 not AR10 … you need to use a regular AR15 [AR10] buffer when using an A5 extension with an AR10 platform. Your AR10 BCG is longer than your typical AR15 BCG … thus you need a regular AR15 [AR10] length buffer … go with an H3 …

Another example people mismatching buffer setups on AR10s, which is an easy thing to do.
Click to expand...
Did you mean this?
 
msgriff said:
Generally, an AR-10/308 rifle length spring works, but there are exceptions. KAC and LMT use the action system that we're talking about, and have different springs for their large frame rifle length and carbine actions. The most common spring used is an ArmaLite #EA1095, which they use for both rifle and carbine AR-10 actions.
Click to expand...
Do you think a LMT 308 Action spring with a carbine size buffer will be correct, since it’s basically impossible to find the armalite spring?
 
thehun said:
No … I’m sorry but can you not read?

HE NEEDS A REGULAR AR15 BUFFER IN H3 weight when using an A5 extension with an AR10 … NOT another A5 length buffer …
Click to expand...
I can read. I could easily ask you the same question and question your comprehension. You don’t have to be a dick. There is a lot going on here in an unorthodox system.

ETA: @lancegastrong I called “Forward Control Design” and inquired. They recommend AR15 carbine buffer H2 with orange Springco spring.
 
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FredHammer said:
Ok, just checking. So would you concur a lighter 5.33oz buffer of A5 length should do the trick?
Click to expand...

It's been explained but maybe this will help. The SR25/AR308/A5 receiver extension (buffer tube) is 3/4" longer than a AR-15 RE so that AR-15 carbine buffers and springs can be used in an SR25/AR308.

Vltor fucked everything up with the A5 naming convention. It does not apply to the SR25/AR308. A5 really only applies to the Vltor proprietary length buffer.
 
FredHammer said:
I can read. I could easily ask you the same question and question your comprehension. You don’t have to be a dick. There is a lot going on here in an unorthodox system.

ETA: @lancegastrong I called “Forward Control Design” and inquired. They recommend AR15 carbine buffer H2 with orange Springco spring.
Click to expand...
No. You were wrong and that’s ok. FCD essentially gave you the answer I did …
 
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thehun said:
No. You were wrong and that’s ok. FCD essentially gave you the answer I did …
Click to expand...
You were wrong too. I think everyone from the OP to each poster was wrong. So I decided to pick up the phone and confirm with the people selling this stuff. End goal, the OP knows what direction to go. Fantastic learning experience for all.
 
This is like the 20th thread about AR10s and buffer setups.

If you are going to run a collapsible stock setup with a large frame AR10 (traditional) … this is the matched, no brainer kit you guys need.

If you have to use heavier buffer weights than what is included by LMT here … you have to looking into your gas control.

lmtdefense.com

MWS BUFFER TUBE KIT - LMT Defense

LM308BTK
lmtdefense.com lmtdefense.com
 
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FredHammer said:
You were wrong too. I think everyone from the OP to each poster was wrong. So I decided to pick up the phone and confirm with the people selling this stuff. End goal, the OP knows what direction to go. Fantastic learning experience for all.
Click to expand...
I was not wrong. OP used A5 extension with an A5 buffer on an AR10 … can’t do that. I said he will need a regular AR15 buffer either a H2 or H3 … FCD told you essentially the same. You said just go use another A5 buffer that weighs less … that recommendation was and still is 100% wrong … his gun will never function with an A5/A5 combo properly on an AR10 … on an AR15 … yea. AR10, never.
 
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FredHammer said:
You were wrong too. I think everyone from the OP to each poster was wrong. So I decided to pick up the phone and confirm with the people selling this stuff. End goal, the OP knows what direction to go. Fantastic learning experience for all.
Click to expand...
would've been better off calling Slash at HeavyBuffers. He's the specialist for AR-10 buffers.
 
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UpSideDown said:
Hang on, you can pull your bolt back to the point at which the bolt lock engages, but a loaded magazine with the bolt locked back has its rounds occluded by the bolt? That should be impossible. The bolt catch is behind the magazine. Check that the tang on your bolt catch that engages the magazine follower isn’t broken or short. That would explain why you can’t chamber a round from there and why your gun doesn’t lock back on empty - the magazine followed isn’t engaging the latch. Also confirm you have the right bolt catch for your lower.
Click to expand...
You can force an A5 extension with an A5 buffer to manually lock back on an AR10 but it will never actually work while trying to run the gun …
 
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thehun said:
I was not wrong. OP used A5 extension with an A5 buffer on an AR10 … can’t do that. I said he will need a regular AR15 buffer either a H2 or H3 … FCD told you essentially the same. You said just go use another A5 buffer that weighs less … that recommendation was and still is 100% wrong … his gun will never function with an A5/A5 combo properly.
Click to expand...
You can be king of snipers hide today. I’ll send you a paper crown if this makes you feel all better. I cut through the shit and got the straight scoop. The answer was neither of what you or I suggested. Now stop acting like a 12yr old.
 
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lancegastrong said:
Do you think a LMT 308 Action spring with a carbine size buffer will be correct, since it’s basically impossible to find the armalite spring?
Click to expand...
The LMT #LM308A9 is fine. It's a long story on the ArmaLite issue and where to get them. I would NOT use a Sprinco Orange, they were designed for standard AR-15 RE using the 308 short carbine buffers (2.5" long). And from your pic post with the suppressor that you're running, an H3 buffer would be a starting weight.
 
thehun said:
You can force an A5 extension with an A5 buffer to manually lock back on an AR10 but it will never actually work while trying to run the gun …
Click to expand...
I deleted my post, I misread thinking he was referring to an A5 spring, not the buffer itself. The extended length A5 buffer would definitely be an issue.
 
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FredHammer said:
You can be king of snipers hide today. I’ll send you a paper crown if this makes you feel all better. I cut through the shit and got the straight scoop. The answer was neither of what you or I suggested. Now stop acting like a 12yr old.
Click to expand...

lc6LbX2.gif
 
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thehun said:
This is like the 20th thread about AR10s and buffer setups.

If you are going to run a collapsible stock setup with a large frame AR10 (traditional) … this is the matched, no brainer kit you guys need.

If you have to use heavier buffer weights than what is included by LMT here … you have to looking into your gas control.

lmtdefense.com

MWS BUFFER TUBE KIT - LMT Defense

LM308BTK
lmtdefense.com lmtdefense.com
Click to expand...

Or, just buy the components from the same source. I built a "mostly" Wilson AR10, bought the Wilson AR10 buffer, spring and RE and DANG if it didn't run perfectly right out of the box. 😳

I use VLTOR A5's on all of my AR15 builds, but RESISTED the temptation to pretend I was building an AR15 because I wanted it to actually work.

Nice to see yet another my AR10 doesn't work thread.
 
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FredHammer said:
You can be king of snipers hide today. I’ll send you a paper crown if this makes you feel all better. I cut through the shit and got the straight scoop. The answer was neither of what you or I suggested. Now stop acting like a 12yr old.
Click to expand...
The answer you got is practically exactly the answer I provided ... LITERALLY ... wow ... you truly can't read ...
 
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hkguns said:
Or, just buy the components from the same source. I built a "mostly" Wilson AR10, bought the Wilson AR10 buffer, spring and RE and DANG if it didn't run perfectly right out of the box. 😳

I use VLTOR A5's on all of my AR15 builds, but RESISTED the temptation to pretend I was building an AR15 because I wanted it to actually work.

Nice to see yet another my AR10 doesn't work thread.
Click to expand...
I do the same! Matched parts = no issues ...
 
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FredHammer said:
I can read. I could easily ask you the same question and question your comprehension. You don’t have to be a dick. There is a lot going on here in an unorthodox system.

ETA: @lancegastrong I called “Forward Control Design” and inquired. They recommend AR15 carbine buffer H2 with orange Springco spring.
Click to expand...

You called an aftermarket parts manufacturer to get an answer to an OEM question and they gave you a partially incorrect answer. Shocking results.

The SR25/AR308 7 3/4" receiver extension uses AR-15 carbine buffers and AR-15 carbine buffer springs.

SprinCo Orange buffer springs are for AR308s with 7" receiver extensions.
 
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