16” vs 18” suppressed .308

[Goldbears93]

Hi there!

I have recently been looking at grabbing a 16” Daniel Defense or Larue in .308. I have been running an 18” gas 308, but wanted to shave some pounds and a couple inches off the barrel for Stalk hunting.

something I was curious about however was how much worse does the recoil get in 308 dropping from an 18” rifle length gas system to a 16” intermediate or mid gas system?

I also will be shooting exclusively suppressed, and was wondering if anyone could speak on how much louder a suppressed 16” vs 18” is?


Past that, is there anything I can do to mitigate the increased felt recoil in a 16” such as some secrets with the buffer or buffer tube or BCG?

trying to weigh the benefits of a shorter/ lighter gun with a little heavier recoil/louder gun and would love yalls opinion or experience.

thank you so much!

 

[FCS]

I doubt you'll notice an appreciable difference in noise between a 16" and 18" suppressed rifle, at least to my ear there isn't a huge difference.
While the LaRue TranQuilo is heavier can, it is a lower back pressure can. I would highly recommend going with a TranQuilo. Bang for buck, the TranQuilo is hard to beat for a gas gun can.
If looking for softest shooting rifle possible, go longer gas system, port sized around burn rate / charge weight / bullet weight that will be used and a heavier buffer. Adjustable gas block wouldn't be a bad idea also.
"Problem" is that you'll have a system that is a little more sensitive to ammo changes, if you really want to make rifle as soft shooting as possible.

 

[Ape_Factory]

The POF Revolution has a 16" barrel but has a rifle-length gas system. It's also substantially lighter than the other two options you mentioned. I went with an OSS HX-QD 762Ti can (flow through) so the gun will run with or without, no modifications. It's as easy to shoot as an AR15 with a hot load.

 

[GUNNER10]

I shoot a 13.5, 16 and 18 inch barrel out of my MWS and honestly, there really is not that significant of a difference, the rifle length gas system on the 18 inch may feel a little softer but I would have to shoot back to back to be sure.

My favorite barrel at the moment is the 13.5 with Sandman K

 

[Mike_Honcho]

I moved from a 20" -> 16", both with non adjustable gas blocks. There was an impulse difference. Position / sling / hand pressure all become just that much more important. Does that make the recoil worse? No, it makes the impulse slightly different. Suppressed sound? Granted I have permanent damage and a constant ring in both ears, but I'd say no difference.

FWIW - some folks and systems can benefit from adjustable gas blocks / I like Tubb flatwire springs although I can not provide you with data that prove it is 'better'.

 

[YammyMonkey]

Not an AR, but I had the barrel on my issued AI cut from 20" to 16" and I didn't notice any difference in recoil.

 

[AngryKoala]

I shoot a 13.5, 16 and 18 inch barrel out of my MWS and honestly, there really is not that significant of a difference, the rifle length gas system on the 18 inch may feel a little softer but I would have to shoot back to back to be sure.

My favorite barrel at the moment is the 13.5 with Sandman K

I am assuming you installed an AGB?

 

[GUNNER10]

I am assuming you installed an AGB?

Nope.

Only thing changed was an extra heavy, 9oz buffer.

 

[AngryKoala]

Nope.

Only thing changed was an extra heavy, 9oz buffer.

How is the gas to the face?

 

[GUNNER10]

How is the gas to the face?

Honestly.

I really don't notice any gas. I find dead airs claim that they are low back pressure to be accurate.

With full size Gemtech GMT300wm, the rifle was violent and unstoppable.

 

[NHPiper]

Late to the thread, but I am running a 12.5" 308 Barrel from Ballistic Advantage. I found the key to the build was the Seekins Switchblock and an extra heavy buffer, like really heavy. With the Switchblock, I can go from suppressed (Sig 762Ti QD) to non suppressed with no issues. It is a loud mo-fo without a can on it, but the recoil isn't really any different than a 16" barrel.

Gas to the face isn't any different than an AR15 with a good gas block.

 

[AngryKoala]

So could you not just adjust an MWS to shoot as soft as the KAC? Maybe switch out the trigger to a geissele.

 

[GUNNER10]

So could you not just adjust an MWS to shoot as soft as the KAC? Maybe switch out the trigger to a geissele.

As somebody who has both, I would say maybe. For example, My 13.5 MWS with a break is pretty close in feel to the 16 inch KAC with FH. I think that once a break or comp is mounted on the KAC, i think the KAC might be more noticeably a softer shooter, but I think that difference could be mitigated to some extent with a BRT gas tube.

Both are great rifles, but I am not sure the KAC is worth almost double what a LMT goes for in non panic times. While the LMT in its lightest trim is about a pound heavier than the ACC, I personally don't see any area where that weight is going to make or break a shot in 99.99 percent of the type of shooting I do. If I needed a field gun, the ACC would make a little more sense,

 

[AngryKoala]

As somebody who has both, I would say maybe. For example, My 13.5 MWS with a break is pretty close in feel to the 16 inch KAC with FH. I think that once a break or comp is mounted on the KAC, i think the KAC might be more noticeably a softer shooter, but I think that difference could be mitigated to some extent with a BRT gas tube.

Both are great rifles, but I am not sure the KAC is worth almost double what a LMT goes for in non panic times. While the LMT in its lightest trim is about a pound heavier than the ACC, I personally don't see any area where that weight is going to make or break a shot in 99.99 percent of the type of shooting I do. If I needed a field gun, the ACC would make a little more sense,

Thank you for the explanation. I'll just have to shoot both. It seems like people have the same sentiment as always going back to JP and KAC.

 

[GUNNER10]

Thank you for the explanation. I'll just have to shoot both. It seems like people have the same sentiment as always going back to JP and KAC.

Jp makes awesome stuff and I would love to eventually grab one of their 308's or 6.5s and tune them for a single round.

At the end of the day, there are alot of great choices out their today

 

[Slevin182]

Only experience shooting large-frame ARs is with .308 in 16", and then 18" barrels, both rifle length gas. I can't say there was a noticeable change in recoil. I also did not run the two barrels back to back. JP FMOS BCG w/ HP Bolt, JP Heavy SCS.

 

[gac700]

Look at VSeven’s 16” .308 or 20” 6.5 Creedmoor. I purchased the 6.5 and returned my lower to have a lighter 16” 308 upper fit for thermal hog hunting.

Great service and both uppers are running smooth with TB suppressors.

The woman I dealt with via a phone call provided exceptional service. I think she is the owners wife and he was a friend and coworker of John Noveske.

 

[strikeeagle1]

I have a 16" & 20" OBR and use a SOCOM2 can. The 16" can reach out to 800-900 meters with common factory ammo. There is a reason Bryan Litz chose the OBR for inclusion in his Extended Long Range Shooting textbook. Don't appreciate any difference in recoil pulse between a few inches of barrel length in 7.62.

 

[Ocean_Dweller]

When getting my night hunting rig set up with an 18" barrel and rifle length gas system, I ran into some issues when suppressed. My barrel had the fixed gas block that came with the Noveske barrel and it was extremely over gassed suppressed but ran fine unsuppressed. I tried a bunch of different things and in the end, had no choice but to install an adjustable SLR gas block even after installing a tungsten buffer. After those changes, my rifle runs like a sowing machine and recoil is so light that I can stay in my thermal while shooting as many rounds at hogs as needed.

A buddy of mine just did the same thing to his AR 308 (SLR gas block, tungsten buffer) and was amazed and the recoil reduction.

 

[teddyw19]

Slapping a can on it will reduce recoil and help you spot your shots for sure

 

[JLTX]

Running a TBAC Ultra 7 on an 18” Seekins 308. Took a while to get the gas adjusted correctly. Once adjusted, a slight positive recoil delta, but zero blowback towards the shooter. POI only shifted .1mil. Reading through previous threads on this topic, the biggest impact on the OPs question is the type and quality of the gas system. When my barrel runs out, I will definitely upgrade the gas system. The SP10 is a great gun and the TBAC Ultra 7 (as recommended by Seekins) has made it better for my ears.