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Uffdaphil
8 May 2020, 10:03
Specs; Aero .308 upper/lower/parts kit, Faxon 18” pencil bbl - rifle gas, adjustable gas block, Lantac E-BCG (black nitride), RE10 extension w/extra power spring and H3 buffer.

No problems suppressed with AGB closed down several clicks. W/O can bolt will lock back but not eject the case. Pulls from chamber and lies loose in upper even with gasblock fully open.

I’ll try swapping the BCG from my factory 16” mid-gas MI gun that runs well both ways. Any other ideas to try? Could the extra venting of the enhanced bcg require a different weight buffer? I’m fine with making this a dedicated suppressed rifle if need be.

fledge
8 May 2020, 11:10
I’d try a lighter buffer and/or lighter spring. Sounds like you’re stacking up the tension to limit operation. Try the other BCG too but I doubt that’s the issue.

I had a similar issue with a 308 BA barrel. Wide open gas block, light buffer, and it still wouldn’t cycle unsuppressed. I sent the barrel back to BA and they opened up the port.

Uffdaphil
8 May 2020, 11:29
Thanks Fledge. I’ll try the spring/buffer first as I have spares.

BoilerUp
8 May 2020, 15:15
I agree with Fledge - the first think I'd do is drop that extra-power spring.

Also, which ammo? My limited experience suggests that when you are on the edge of having a tuned system there is a pretty big difference between commercial .308 vs milsurp 7.62, which the latter being comparatively underpowered.

mustangfreek
8 May 2020, 16:23
Single or double extractor?

Try with or without insert or different spring maybe

Uffdaphil
8 May 2020, 19:35
I agree with Fledge - the first think I'd do is drop that extra-power spring.

Also, which ammo? My limited experience suggests that when you are on the edge of having a tuned system there is a pretty big difference between commercial .308 vs milsurp 7.62, which the latter being comparatively underpowered.

Don’t you mean the former is underpowered as in .223 vs 5.56? I was using German Nato 7.62.

Uffdaphil
8 May 2020, 19:43
Single or double extractor?

Try with or without insert or different spring maybe

I had an extractor spring issue with a 6.8 SPC build, but the problem was not releasing the case which is not the case here. Doubt the super expensive bolt design is at fault.

I was using the long orange EP spring,and now,I see people saying the shorter red sprinco is correct with the RE 10. So much mis-information out there. I will try different combinations of springs/buffers and report back.

gatordev
8 May 2020, 19:46
Don’t you mean the former is underpowered as in .223 vs 5.56? I was using German Nato 7.62.

308/7.62 is backwards compared to .223/5.56. I'm guessing this was done to keep the Commies guessing.

Uffdaphil
8 May 2020, 20:01
Amazing! At 71 I still learn new things daily.

mustangfreek
9 May 2020, 01:00
Ok, read to fast, seen your using a Lantac

I see you have a good idea of what’s going on.

Also , something I always check now and shim if needed.

How much clearance between your bolt and bolt catch when you rack it all the way back? Good rule of thumb is about a nickel worth of gap. I always shrink mine a hair. But not too much..

BoilerUp
10 May 2020, 21:56
I was using the long orange EP spring,and now,I see people saying the shorter red sprinco is correct with the RE 10. So much mis-information out there. I will try different combinations of springs/buffers and report back.

A RE10/A5 extension is the same as an Armalite length AR-10 buffer, so for .308 you'd use an AR-15 sized buffer and an Armalite pattern springs (Armalite part #EA1095). According to SpringCo, the RED is correct.

Uffdaphil
11 May 2020, 00:24
Stang. Bolt catch clearance is good.

Boiler. Yes, I saw Sprinco says red spring for the RE10. Somewhere else said use the orange which I had installed. Hopefully the red cures the problem. Might be a couple weeks before I get back to the range to test.

Thanks everyone for chiming in.

BoilerUp
11 May 2020, 07:00
Stang. Bolt catch clearance is good.

Boiler. Yes, I saw Sprinco says red spring for the RE10. Somewhere else said use the orange which I had installed. Hopefully the red cures the problem. Might be a couple weeks before I get back to the range to test.

Thanks everyone for chiming in.

I'll also add that since you have an AGB you might end up being happier with the Armalite EA1095 spring instead of the Springco Extra Power spring, especially if you normally shoot 7.62x51. The main advantage of an AGB is you can tune your gas so you don't need a stronger spring in the first place.

UWone77
11 May 2020, 10:34
I just installed 2 Orange Springs into my 12.5 308 SBR and a 16" 308, both Aero M5's.

Still waiting on the PD range to open so I can see if they run better. Not any issues right now, but I know the Orange Spring is recommended if you're using an AR15 length receiver extension. I'd use the 308 buffer instead of the H3 to start.

BoilerUp
11 May 2020, 11:06
I just installed 2 Orange Springs into my 12.5 308 SBR and a 16" 308, both Aero M5's.

Still waiting on the PD range to open so I can see if they run better. Not any issues right now, but I know the Orange Spring is recommended if you're using an AR15 length receiver extension. I'd use the 308 buffer instead of the H3 to start.

Isn't the 308 buffer the short stubby one? If so, that should only be used in the AR15 carbine length buffer tubes as those are too short for the AR10/A5 extensions. I made the mistake once of running a 308 buffer in a AR10 extension and ended up damaging the threads on the rear of the lower receiver from bcg over travel.

That said, in principle I think you are right as the .308 buffer is about the same weight as an H buffer, so I'd probably start with an H instead of the H3.

UWone77
11 May 2020, 11:57
Isn't the 308 buffer the short stubby one? If so, that should only be used in the AR15 carbine length buffer tubes as those are too short for the AR10/A5 extensions. I made the mistake once of running a 308 buffer in a AR10 extension and ended up damaging the threads on the rear of the lower receiver from bcg over travel.

That said, in principle I think you are right as the .308 buffer is about the same weight as an H buffer, so I'd probably start with an H instead of the H3.

Ahhhh good catch. I didn't see he was using an RE10 receiver extension.

And you are correct. DO NOT USE the short buffer on anything other than an AR15 extension.

mustangfreek
11 May 2020, 15:48
Yep, went thru this confusion also. It’s now engraved in my brain

Standard ar15 length is shorty 308 buffer

I use the full armalite kit with their A5 length tube, spring and H3. It was 65 shipped last year when I got it.

I tried a H2 and it was noticeably more violent.. h3 is on now and could almost use more

Uffdaphil
21 May 2020, 19:22
Happy day at the range. Sprinco red spring with the same H3 buffer solved the problem. For some reason Pmags all locked back on a single round while a Lancer .308 would not. Stiffer metal feed lips? Opening the AGB one click fixed that. Now runs good with and w/o Recce 7. Had to zero with a 3-9 scope as my 18x ran out of windage adjustment. Need more fine tuning, but I’m optimistic.

More fun was getting the 16” coupon Ultramatch dialed in. About an inch difference POI with the Recce 5 which I zeroed using a 2.5-12x. Met another oldster who hadn’t touched an AR since his Air Force M16 nearly 50 years ago and had never shot with a silencer. First time - seven shots with four touching in about a 1.5 inch group with Wolf Gold! Range was closing so I’ll go for my groups another day and with better ammo.

BoilerUp
21 May 2020, 20:21
Happy day at the range. Sprinco red spring with the same H3 buffer solved the problem. For some reason Pmags all locked back on a single round while a Lancer .308 would not. Stiffer metal feed lips? Opening the AGB one click fixed that. Now runs good with and w/o Recce 7. Had to zero with a 3-9 scope as my 18x ran out of windage adjustment. Need more fine tuning, but I’m optimistic.

More fun was getting the 16” coupon Ultramatch dialed in. About an inch difference POI with the Recce 5 which I zeroed using a 2.5-12x. Met another oldster who hadn’t touched an AR since his Air Force M16 nearly 50 years ago and had never shot with a silencer. First time - seven shots with four touching in about a 1.5 inch group with Wolf Gold! Range was closing so I’ll go for my groups another day and with better ammo.

Glad you got it running with a simple change.

I shoot a lot of Wolf Gold and love it, but I wouldn't expect 1.5 MOA from it. Nice.

Uffdaphil
21 May 2020, 21:23
Glad you got it running with a simple change.

I shoot a lot of Wolf Gold and love it, but I wouldn't expect 1.5 MOA from it. Nice.

I wouldn’t expect that with me shooting either. My eyes are terrible. My 77 grain is reserved for this gun in future.

gatordev
22 May 2020, 02:39
Happy day at the range. Sprinco red spring with the same H3 buffer solved the problem. For some reason Pmags all locked back on a single round while a Lancer .308 would not. Stiffer metal feed lips?

When I was battling my over-gassed .308, I found that the PMAGs would still feed but the Brownells metal mags wouldn't. After looking at the brass, it was clear that the brass was "binding" due to friction on the metal where as the polymer on the PMAG was more slippery and fed better. Obviously the whole system wasn't operating correctly, but it was interesting to see how much more friction the metal mag causes.

Uffdaphil
23 May 2020, 08:20
I neglected to state the good Wolf Gold shooting was just at 50 yds so not as amazing as it sounded. My bad.

gatordev
23 May 2020, 11:24
I neglected to state the good Wolf Gold shooting was just at 50 yds so not as amazing as it sounded. My bad.

I've actually wondered why many on the internet haven't started just shooing 1-round groups. This seems to be the ultimate way to show one's shooting prowess. Every group is sub-MOA!

Joelski
23 May 2020, 11:50
Might a little shot of dry lube help that problem? I can't say for sure, but what can it hurt? I do it to my metal mags and they're trouble-free.

bfoosh006
4 August 2020, 19:59
FYI... here is some measured info on recoil springs. And this is various recoil springs on the same setup.

A2 (old) - 7.6lb closed, 14.5lb open
A2 (new) - 9.1lb closed, 16.7lb open
Tubb Flatwire - 10.5lb closed, 16.3lb open
Tubb .308 Flatwire - 13lb closed, 16.7lb open
SpringCo White ? (standard) - 8.3lb closed, 16.3lb open
SpringCo Red (extra) - 10.5lb closed, 18.4lb open
SpringCo Orange (increased) - 13.9lb closed, 24.8lb open

From this video.
[URL="https://www.youtube.com/watch?v=8fMVZbrnvu8"]https://www.youtube.com/watch?v=8fMVZbrnvu8[/URL

As for your issues with the Lancer mags.... IMHO they have VERY strong mag springs, enough so that the follower can cause drag on the BCG.

At least they do on my Large Frame AR's... all of them

Uffdaphil
5 August 2020, 08:56
Good to know info on the springs. The mag dry lube sounds like a good idea. Anyone recommend a brand?

Joelski
5 August 2020, 12:00
WD-40 Makes a spray on Dry lube. I got mine on AMAZON

Uffdaphil
5 August 2020, 13:12
Thanks.