Advice on a silenced 308 gasser?

[Twinsen]

I have fired an SR25 suppressed from a tripod, but didn't inspect brass, accuracy test, etc. It was a huge, heavy rifle though and the prices are kinda silly.

The can I was hoping to use on a little 308 AR was a TBAC Ultra 7.

I'll reach out to POF first. The size and weight appeal to me. Heavier than the DPMS, but not so heavy I wouldn't hunt with it.

 

[sinister]

You'll never be happy with a carbine- or mid-gas length DPMS of ANY configuration with a suppressor.

Let it go. Buy something off-the-shelf that works. KAC and HK are two turn-key options. Be prepared to spend money.

 

[TonyTheTiger]

What thread did that happen in?

Or are you suggesting your post was helpful?

Good strategy. Keep deflecting and acting snarky and maybe people will forget you started this thread just to bitch.
And no, I have no intention of being helpful. How's that saying go? Something about leading a horse to water but being unable to make it drink?

 

[nn8734]

Mildly entertaining thread.

OP just needs to buy a KAC, stick a lightweight optic on it (mk6 1-6, NX8, etc) and be done. ACC would be perfect for what he wants.

 

[hlee]

I posted here for advice on a 308 AR platform, like I said several times. A bunch of people threw out suggestions and helped me. Some people wanted to diagnose my rifle, and I did not, but I gave them info about it anyway.

Whatever you're going through, you'll be ok. Cheer up, tiger.


Sorry to hear you had a bad day. Cheer up, sport.

No bad day here. My rifles all function. Cheer up, sport.

 

[blackblue]

I have fired an SR25 suppressed from a tripod, but didn't inspect brass, accuracy test, etc. It was a huge, heavy rifle though and the prices are kinda silly.

The can I was hoping to use on a little 308 AR was a TBAC Ultra 7.

I'll reach out to POF first. The size and weight appeal to me. Heavier than the DPMS, but not so heavy I wouldn't hunt with it.

Ultra 7 will be a main cause of that, ran into that issue on my 6.8spc they create quite a bit of back pressure.

 

[j-huskey]

You'll never be happy with a carbine- or mid-gas length DPMS of ANY configuration with a suppressor.

WORD !
TRUTH !
GOSPEL !
REALITY !

My previous experience with any DPMS has been they suck. With cans, they suck worse. We will no longer approve anything DPMS in my hood where buy your own to carry is allowed.

My GA Precision Armalite AR10A "HAD" problems without the can. @sinister and AMU helped fix that, a looong time ago...
Now it runs canned or not.
Listen to Sinister on these things ppl...

My next two built Armalite AR10's followed Sinister's advice. All three have run well since 2009...... yes, 2009....

Guns were heavy, like the OP's experience w KAC.. but, they run.

AND like the OP, I wanted a lighter big bore for night walking about that would run w a can.

Bought two 16" Armalite super light Defender/Sports models... started out pulling the factory handguard and gasblocks, added a longer hg to mount clip on nv/thermal and added AGB, running a Silencerco Harvester and an OLD ASS "JET" (sacrilege sacrilege)..
Neither have failed to function yet.

I have seen way too many big bore AR's that were built by idiots (DPMS G2 qualifies) that were the stuff of recurring PTSD nightmares. The majority were overgassed by short gas systems and nothing u could do would fix them (EXCEPT replace the pos barrel with the longest gas system u could put on it. )
The swapping of ALL the listed parts in this thread might have solved a few of the nightmares but, a lot of work for big $.

Listen to @sinister when he speaks. He knows this subject.
Hi Dave !

Best to u all.

 

[Twinsen]

The KAC I fired was an m110 setup, or possibly was an m110. Trey was showing it off.

Honestly, I'd be fine with running a can 100% of the time and cleaning it constantly. So rifle gas, or heck, gas trap. I'll look around. If I went with putting parts together, all the info is in this thread.

Thanks, guys.

 

[Cold_Bore_88]

So with the SLR have you closed the gas completely off then opened it up 1 click and fired 1 round at a time in a mag until the carrier locks back?

Google searching the dpms it looks like it has a long dwell length which is just horrible from the start for suppressed use.

Do you have any lower back pressure suppressors like a 762 rc2, sandman s, oss, or ?

If looking for a factory rifle, if it comes from the factory without an adjustable gas block I wouldn't bother unless you have an oss. It will be tuned for use without a can and you will need to do the same thing with adding a gas block or increasing buffer weight.

Personally I would build one off a Zev or Mega receiver set and handguard. Rifle length gas or longer depending how long you want your barrel. SLR or superlative gas block, JP fmos bcg, A2 tube and buffer. That is essentially my large frame build. Zev, proof research, jp fmos, slr adjustable gas, A2 tube with a kynshot large frame rifle length buffer, jp spring.


This is the layout of my 6.5cm zev build.

While I don't have thousands of rounds on it as this is a relatively newish build and current 6.5 ammo prices are ridiculous but I shoot it suppresed 100% of the time. Roughly 800 rounds, multiple ammo types. I've used my omega, Nomad and Nomad L. It's never malfunctioned. Consistent rearward ejection. Very pleasant smooth impulse.

I've helped a friend build a mega large frame 308 without any issue suppressed as well. Similar formula. JP bcg, adjustable gas, a2 buffer, jp spring, I can't remember the barrel but I think it was a Criterion rifle length 18".

I've had a guy at the range next to me with a suppressed large frame pws. Seemed to work quite well.

I agree with this.

A similar setup/combination of parts got mine running smoothly. I am using a 20” Krieger M110 barrel with rifle length gas. SLR adjustable gas block, JP spring (cut down a bit), etc.

I would like to grab a LMT enhanced BCG as well. Those can help to run suppressed.

 

[KTB1680]

So with the SLR have you closed the gas completely off then opened it up 1 click and fired 1 round at a time in a mag until the carrier locks back?

Google searching the dpms it looks like it has a long dwell length which is just horrible from the start for suppressed use.

Do you have any lower back pressure suppressors like a 762 rc2, sandman s, oss, or ?

If looking for a factory rifle, if it comes from the factory without an adjustable gas block I wouldn't bother unless you have an oss. It will be tuned for use without a can and you will need to do the same thing with adding a gas block or increasing buffer weight.

Personally I would build one off a Zev or Mega receiver set and handguard. Rifle length gas or longer depending how long you want your barrel. SLR or superlative gas block, JP fmos bcg, A2 tube and buffer. That is essentially my large frame build. Zev, proof research, jp fmos, slr adjustable gas, A2 tube with a kynshot large frame rifle length buffer, jp spring.


This is the layout of my 6.5cm zev build.

While I don't have thousands of rounds on it as this is a relatively newish build and current 6.5 ammo prices are ridiculous but I shoot it suppresed 100% of the time. Roughly 800 rounds, multiple ammo types. I've used my omega, Nomad and Nomad L. It's never malfunctioned. Consistent rearward ejection. Very pleasant smooth impulse.

I've helped a friend build a mega large frame 308 without any issue suppressed as well. Similar formula. JP bcg, adjustable gas, a2 buffer, jp spring, I can't remember the barrel but I think it was a Criterion rifle length 18".

I've had a guy at the range next to me with a suppressed large frame pws. Seemed to work quite well.

Who and how- that camo pattern is amazing!

 

[Clayman]

Who and how- that camo pattern is amazing!

Deadlock coatings fighter cam in dcu

 

[smarcus]

I have an SR25 ECC with a direct thread Sico Omega. Runs like a top but I don’t pay attention to the brass cause I don’t reload. But M80, MEN, Federal 168 and 175 SMK, Fusion all run just fine.

As far as DPMS pattern builds I’ve had issues with 6.5 CM and 6mm CM but 308 builds have never been an issue. All used SLR adj gas blocks and a mix of springs and buffers depending on the build.

 

[accurate_okie]

I'm going to chime in as I have had problems with 308 DPMS pattern 308.

I bought a V7 lightweight BCG and they recommended the below buffer system. After assembly I find out that the gas port on the Xcaliber barrel was shaped like wine glass and way to small after sending V7 and they fixed it. They drilled it out to 0.086" and tested with the same can I have. Fast forward 3 years later and I still have yet to have an issue after initial gas adjustment. I only run this rifle with a silencer.

Aero M5 receiver set
Armalite AR10 6 position receiver extension kit comes with an H3 buffer, none of that short buffer crap
V7 lighweight BCG
Xcaliber 308 18" rifle length gas system
SLR AGB
SiCo 3 chamber break and omega

And that's my two cents.

 

[Ape_Factory]

POF Revolution DI with an OSS 762 Ti. Zero difference suppressed or unsuppressed. The more I shoot my POF the more I like it. Just eats everything, no failures to function and with a good load is sub MOA. And it's under 7 pounds, same size as an AR15. Hard to beat.

Gas is rifle length. Was shooting it on Sunday and a guy at the other end commented on how quiet it was. I had to tell him it was a .308 and he was actually surprised. Comes with an adjustable gas block that's super easy to access and adjust too. Just a really well thought out rifle.

 

[BobA]

There is a wealth of disinformation out there and I've wasted a few thousand dollars trying to get a 308 AR running with a can. If you have a suppressed rifle with a low round count that you don't actually shoot, please don't chime in. I realize how rude that is, but I really don't want to blow more money on stuff that doesn't work but is photogenic.

In front of me, I have my DMPS G2 with an SLR adjustable gas block, Vltor A5 receiver extension, and 8.5oz heavy buffer. It does not work. I am not interested in fixing it. The adjustable gas block and the receiver extension with heavy buffer were both guaranteed to work, but $400 later the gun is exactly the same. I can find 50 threads of people saying they would work.

I've tried DPMS, DPMS G2, and Quentin Defense. I've bought aftermarket "DPMS pattern" receiver sets that do not accept DPMS pattern parts. I literally went to a DPMS crate and tried dozens of their receivers, uppers and lowers, and wasn't able to find two that worked together. I went to GAP and asked them about running a gasser with a can and they said don't bother, they don't recommend it.

Is there a modern gas gun in 308 that can function with a silencer? Have you actually done it?

I am in AZ, so I'm going to reach out to POF and see if I can test fire one of their units. It's sad to me that every gasser AR15 I've touched has worked perfectly, but not one 308 AR that worked at all.

I have SIG 516 308 and run a Silencerco Hybrid with 30 cal cap. Adjust gas block to "supressed" setting and never an issue through 500 rounds or so.

 

[Supervel]

I


It all comes down to selecting the right tool for the job, you have the right can for your rifle but for some reason, you are throwing a bunch of time and money at getting it running with the wrong cans.

Ive been shooting large frame AR's suppressed for almost 15 years now and have never had to run an adjustable gas system. The only time that i experienced an issue was when I attempted to run a high pressure, full size Gemtech GMT-300WM on my 13.5 and 16 inch LMT MWS 308 barrels with their intermediate gas systems.. This was a can that caused zero issues on my 18 and 20 inch MWS barrels with rifle length gas system

This combination caused violent recoil as well as failures to feed. This issues were successfully addressed by picking up a low pressure Dead Air Sandman K.

Great can choice


Terrible can choice


With this being said, i think there are way too many good options out there to spend time and money messing around with a DPMS,

Daniel Defense DD5 8.6LBS
SR25 ACC 8lbs
LMT MWS with Light weight barrel 8.6lbs
Barret Rec 10 8.25lbs
FN Scar 17 8lbs
Sig 716I 8.5 lbs
POF revolution 7.3lbs

I would pick any one of these and match it with an appropriate can and just be done with it.

I


It all comes down to selecting the right tool for the job, you have the right can for your rifle but for some reason, you are throwing a bunch of time and money at getting it running with the wrong cans.

Ive been shooting large frame AR's suppressed for almost 15 years now and have never had to run an adjustable gas system. The only time that i experienced an issue was when I attempted to run a high pressure, full size Gemtech GMT-300WM on my 13.5 and 16 inch LMT MWS 308 barrels with their intermediate gas systems.. This was a can that caused zero issues on my 18 and 20 inch MWS barrels with rifle length gas system

This combination caused violent recoil as well as failures to feed. This issues were successfully addressed by picking up a low pressure Dead Air Sandman K.

Great can choice


Terrible can choice


With this being said, i think there are way too many good options out there to spend time and money messing around with a DPMS,

Daniel Defense DD5 8.6LBS
SR25 ACC 8lbs
LMT MWS with Light weight barrel 8.6lbs
Barret Rec 10 8.25lbs
FN Scar 17 8lbs
Sig 716I 8.5 lbs
POF revolution 7.3lbs

I would pick any one of these and match it with an appropriate can and just be done with it.

Been reading through this problem ladder,I am curious about the size of the gas port for starters? I also agree w others who mentioned the type/model of can being used. I also have had fine results on customer's 308 ARs with a good gas block and adjusting until solid lockback occurs. I usually add one more click for ammo variance. I also agree with the longest setup possible. Best of luck

 

[ut755ln]

I


It all comes down to selecting the right tool for the job, you have the right can for your rifle but for some reason, you are throwing a bunch of time and money at getting it running with the wrong cans.

Ive been shooting large frame AR's suppressed for almost 15 years now and have never had to run an adjustable gas system. The only time that i experienced an issue was when I attempted to run a high pressure, full size Gemtech GMT-300WM on my 13.5 and 16 inch LMT MWS 308 barrels with their intermediate gas systems.. This was a can that caused zero issues on my 18 and 20 inch MWS barrels with rifle length gas system

This combination caused violent recoil as well as failures to feed. This issues were successfully addressed by picking up a low pressure Dead Air Sandman K.

Great can choice


Terrible can choice


With this being said, i think there are way too many good options out there to spend time and money messing around with a DPMS,

Daniel Defense DD5 8.6LBS
SR25 ACC 8lbs
LMT MWS with Light weight barrel 8.6lbs
Barret Rec 10 8.25lbs
FN Scar 17 8lbs
Sig 716I 8.5 lbs
POF revolution 7.3lbs

I would pick any one of these and match it with an appropriate can and just be done with it.

Really good post, I agree.

 

[epeet]

I built a 308 years ago, 16", mid or intermediate length. Runs fine with my suppressor on it, but the brass does get dinged... Adjustable gas block isn't necessary, I'd play with your buffer weight, suppressor, and ammo choice first.

 

[mtwarych]

My DPMS GII Hunter works. I put an Odin adjustable gas block on it, I put an 11 ounce heavy buffer and a heavy recoil spring on it and the rifle shoots great with or without the Omega 300 suppressor on it.

The rifle shoots about as hard as a Golden Retriever puppy. Before the additions, it was more like an angry mule.

I'm fairly certain the people who offered up their GII fix to you before this dog and pony show had no idea you had such a short gas system.

Your rifle is destroying your brass because your bolt is unlocking and ripping the still under pressure brass out of your chamber long before your barrel uncorks. There is no way to remedy the short barrel/gas length system other than taking the advice of the smarter folks here telling you to lengthen your gas system by changing your barrel. My GII Hunter with the Omega on it is still easy to move around with even with an uncut 20" barrel.

My suggestion is to find a DPMS GII 20" take off and have it cut and threaded as short as possible or buy a barrel from your favorite GII barrel maker.

I hate to say it but you bought a big problem when you bought a "short" barrel with an even shorter gas system.

My condolences.

 

[Twinsen]

I didn't even think of getting a 20" take off cut down.

Thank you.

 

[wyld3man]

I built two 7.62 guns and both run great suppressed. Both were built on Mega upper/ lower and hand guard sets. The one is 18” and has all JP parts on the inside to include barrel and gas block. The other is 16” and is built very similar to the 18”” rifle except for the barrel. I got the barrel for that one from X Caliber, had them put a 1:8 twist on it. I did have initial issues with that one, but it was quickly fixed. I forgot to tell them I was running an adjustable gas block so I had to send it back for them to open the gas port up a little bit. That rifle runs great now and I shoot it often. I use an OSS 7.62 suppressor on both guns. I have another Mega “builders kit” that I am going to build out as a 6.5 Creedmore, probably will use all JP parts again and have X Caliber make a barrel for it.

 

[Twinsen]

I emailed POF, and got nothing out of it. They had a booth at the big gun show here so I talked to them. They were all hype about the product until I asked if can be run with a silencer. Their reaction was discomfort, hesitation, and entirely uncertain phrases.

"Well..."

If I ever get serious about wanting a gasser, I will come back to this thread as a guide to build my own. Thanks again, guys.

 

[Ape_Factory]

That's really strange given that a majority of their guns come with adjustable gas blocks and there are photos/videos of Frank shooting POF rifles with OSS cans and they've recommended them on their own web page in the past.

There's literally no reason why any of their AR's wouldn't run with the right suppressor. With the OSS, there's just no need to tune the gas for it. Now if you're looking at a high back pressure can, yes, there will be tuning involved with ANY rifle that didn't come tuned for a particular suppressor from the factory. So if you were getting questionable looks it was because you weren't providing them with all the details.

Last time out at the range, testing three different loads. $30 Amazon tripod and a cheap, small bean bag. Suppressed with the OSS. No sled, nothing fancy.


I was shooting three loads in development and I am by no means a crack shot. Didn't touch the gun other than an initial scope adjustment with the center target. At 100 yards, top left, Hornady Vmax 180, 10 shot group. Top right, Hornady ELD-X 200gr, 10 shot group. Center, Vmax 150gr, two five shot groups. I shot the 150gr VMax in the center first and adjusted the scope between the two five shot groups, no scope adjustment for the 180, 200 or 150 fmj's. All the hunting loads are still in development and with a bit of tweaking I'm sure I can shrink the groups. Bottom right, a developed "plinker" load, Hornady 150gr FMJBT's, super inexpensive bullet, only an 8 shot group as I wanted to use the rest on the longer range reactive targets. I could hit the small, approx. 6" plate at 200 yards, 2-3 shots per second as it was swinging. Pretty sure with a good bipod and steadier hand, that's a less than MOA load.

 

[Twinsen]

Yikes. I hope you get it figured out. I don't know what their warranty program is, but let us know when you send it in.

My DPMS is bad, but it isn't THAT bad. Damn.

ETA: Is it chewing up the brass?

 

[BamaSE]

I emailed POF, and got nothing out of it. They had a booth at the big gun show here so I talked to them. They were all hype about the product until I asked if can be run with a silencer. Their reaction was discomfort, hesitation, and entirely uncertain phrases.

"Well..."

If I ever get serious about wanting a gasser, I will come back to this thread as a guide to build my own. Thanks again, guys.

The POF Rev is my preferred nighttime rig….I run both the pistol and rifle with a Nomad 30 and one of my buddies runs the rifle with the Omega 300. No issues and many a round downrange beyond count now…..but……be advised there is a break in period to get the rifle and gas tuned right. I think it was 80-100 rounds…..I used mil spec Lake City stuff until I got ready for the final adjustment. Runs great with Hornady ELDxs and Nosler Accubonds.

 

[Ape_Factory]

Yikes. I hope you get it figured out. I don't know what their warranty program is, but let us know when you send it in.

My DPMS is bad, but it isn't THAT bad. Damn.

ETA: Is it chewing up the brass?

Yep, definitely a troll. Don't feed the troll.

 

[Twinsen]

You don't tweak a load down to MOA from 3 MOA. You tweak a load from inconsistent velocity to consistent. There is something wrong with that rifle.

 

[Ape_Factory]

You don't tweak a load down to MOA from 3 MOA. You tweak a load from inconsistent velocity to consistent. There is something wrong with that rifle.

There is literally so much information and data that you do not have to make any sort of assumption like that in regards to my rifle and those loads. I have plenty of sub-MOA loads which did not start out that way. These are just the three latest that I'm working on which would shrink with just some of the basics including a better bipod (on the way). The 150gr. is already an MOA and likely sub with a better shooter behind the gun.

 

[Twinsen]

A 2" group at 100 yards is not MOA.

You know, nevermind. This is what I was talking about at the beginning of this thread. People say something is wonderful without proof and despite proof to the contrary. They just put it out there with no shame.

"nEVeR hAD aNy pRObLeMs wITh mINe"

 

[Ape_Factory]

Thank you captain obvious. I literally had that target photo readily available and posted it as a courtesy to help knowing it wasn't the best nor what the rifle is capable of. It was merely an example that the rifle does indeed work with a suppressor (with zero issues) and quite frankly any of those groupings is more than good enough to take a deer. I've just been experimenting with heavier bullets (currently) to see if I could get them to group with the 1:10 twist. I've shot more than a few sub MOA groups with smaller bullets in the 147 to 167grain range but I just don't have a lot of time to go digging and find those targets, take a pic, upload them to a hosting site and post them. My apologies.

And again, if I'd had a sled, multiple bags, better tripod, etc..., I'm sure they'd all be grouped tighter. That's at a public range with an entire row of other shooters wanting the range to go cold every other shot. Not ideal for trying to get good groups. But to dismiss is just armchair philosophy. I've had wide groups with a super low SD (under 4) and tight groups with an SD in the 40's. Just too much comes into play to nail it down to one specific thing. Maybe read this: https://www.snipershide.com/shooting/threads/dont-blame-the-rifle.7024229/#post-8798307

 

[Twinsen]

The rifle I'd been looking for was to be my new hunting rifle for elk, and none of those groups was good enough for it. A cow elk's vitals are gigantic, near basketball size profile. The bullets I've been using are effective 400-475 yards depending on barrel and temperature. 3.5" x 4.5(hundred yards) = 15.75". That means regularly missing the massive 9 inch basketball I'd be aiming at, assuming I did everything perfectly.

The DPMS G2 has one elk on it. But it destroyed brass and I didn't feel safe firing it.

 

[nickw]

GA precision built a AR10 on a DPMS upper and lower for my department 10+ years ago. 20 inch Bartlein barrel, rifle gas, JP adj gas block. Yankee Hill Machine is local and they set us up w/ a titanium suppressor. We were initially blowing primers with Federal SMK. Talked to GAP and Yankee Hill and they both suggested trying different ammo. We tried some Hornady 168 Amax and had no issues. Never had a problem after that. Ran 168 grain Amax and then ELDm. This was actually a 308 “patrol rifle” that anyone in the department could utilize if needed. The rifle was shot yearly for familiarization after qualifying with 5.56 patrol rifles so it saw descent use. Absolute hammer. Suppressor made it so soft and it was incredible accurate. Everyone wanted to shoot it

 

[n2ishun]

Something I've had issues with that no one seems to have mentioned.
Get a A5 type buffer tube, mine would not run without it (Vltor carbine style on mine).
Regular 308 rifle length buffer spring and the 5.4-5.6 carbine buffer to use with it.
I have a Mega MAten megalythic (or however they spelled it) with a Wilson 18" rifle length barrel.
Yup, as everyone has said the longest length gas system you can get on the barrel is best to offset the dwell time the suppressor adds.
Adjustable gas block is also required if you plan to use both with and w/o the can.
I haven't shot out the barrel yet but I'm close, thousands of rounds with zero issues.
Sorry I do not recall what gas block I bought (and it has no markings) but it's the click adjustable type.
Can on 4 clicks from closed, can off go 3 clicks farther out and it has been perfectly working like this since I built it.
I'll post up a pic when I get a chance.
Here's a pic with a flash can (pig) on it....I had it made to use same mount as suppressor, a bit more accurate too.