Which SBR upper

[Yondering]

On 10/2/2019 at 10:13 AM, Moloch38 said:

I recently purchased a Faxon 5500 and put an Atlas S handguard on it. I love how lightweight it is with the pencil barrel and would love to do a SBR variant. Can I run a 11.5 pencil barrel with their lightened bolt or am I going to run into gas issues? I'd be running a suppressor, but I don't have any experience with suppressors and the lightened BCGs.

 

Moloch, I haven't used that Faxon barrel (and so much depends on gas port size of your barrel), but can offer some general guidelines: Adding a suppressor delivers more gas to the operating system, and requires a restriction in gas if you want to bring it back to the same point as unsuppressed. Using a light weight bolt carrier also requires less gas, because it doesn't take as much force to counter the inertia of that lighter carrier.

 

You definitely can combine the two (suppressor and lighter carrier), but I think you'll need to use an adjustable gas block or some other method of gas restriction (there are several options) to tune the rifle to work correctly. Personally I prefer to use an adjustable gas block anyway since so many AR barrels are overgassed a bit right from the manufacturer. 

 

Also keep in mind that you should expect more POI change when adding the suppressor to that pencil barrel than you would get with a heavier barrel. Nothing wrong with that, just be aware of it and account for it on target. 

[af_tt]

If you decide to and can use a suppressor. I built an upper with the Faxon 11.5 mid length barrel. It is fantastic, recoil impulse is like my full size KAC rifle. I shoot it suppressed 100% though so I cant comment on the unsuppressed reliability.

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[Moloch38]

On 10/7/2019 at 1:36 PM, Yondering said:

 

Moloch, I haven't used that Faxon barrel (and so much depends on gas port size of your barrel), but can offer some general guidelines: Adding a suppressor delivers more gas to the operating system, and requires a restriction in gas if you want to bring it back to the same point as unsuppressed. Using a light weight bolt carrier also requires less gas, because it doesn't take as much force to counter the inertia of that lighter carrier.

 

You definitely can combine the two (suppressor and lighter carrier), but I think you'll need to use an adjustable gas block or some other method of gas restriction (there are several options) to tune the rifle to work correctly. Personally I prefer to use an adjustable gas block anyway since so many AR barrels are overgassed a bit right from the manufacturer. 

 

Also keep in mind that you should expect more POI change when adding the suppressor to that pencil barrel than you would get with a heavier barrel. Nothing wrong with that, just be aware of it and account for it on target. 

I appreciate the feedback. I would definitely be using an adjustable gas block. I spoke to Faxon and they thought it would work fine that way and recommended the 11.5 gunner barrel.

[Moloch38]

On 10/7/2019 at 8:22 PM, af_tt said:

If you decide to and can use a suppressor. I built an upper with the Faxon 11.5 mid length barrel. It is fantastic, recoil impulse is like my full size KAC rifle. I shoot it suppressed 100% though so I cant comment on the unsuppressed reliability.

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Glad to hear it. Are you using the 11.5 gunner barrel? This is the one Faxon recommended over the 10.5. Do you mind if I ask what can you are using and if you like it? It would likely be majority suppressed, but you never know. All my can experience is with surefire cans from my AD days, they were great, but very heavy. I would like to try and find a lighter can, but still keep the overall length down. Still always be shooting with Peltors so noise isn't as much the issue as is muzzle blast in CQB spaces. 

[af_tt]

Glad to hear it. Are you using the 11.5 gunner barrel? This is the one Faxon recommended over the 10.5. Do you mind if I ask what can you are using and if you like it? It would likely be majority suppressed, but you never know. All my can experience is with surefire cans from my AD days, they were great, but very heavy. I would like to try and find a lighter can, but still keep the overall length down. Still always be shooting with Peltors so noise isn't as much the issue as is muzzle blast in CQB spaces. 

Yes the 11.5 gunner, it's fantastic. It shoots well with no suppressor but I havent shot it much without one. I use a gemtech Halo titanium on this rifle and the M4. I have also used my Sandman K. All good options, the Halo titanium handles better with the weight. Just get an adjustable gas block and run the 11.5 it's the best of both worlds.

Edit: the Surefire would work good as well just going to be a bit heavier on the end of the gun.

 

Here is the rifle with suppressor next to a 14.5 M4 with a standard FH. 10.3 with a Sandman K etc. The Colt lower sits a little lower with the shorter stock.

 

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[Moloch38]

On 10/9/2019 at 9:05 AM, af_tt said:

Yes the 11.5 gunner, it's fantastic. It shoots well with no suppressor but I havent shot it much without one. I use a gemtech Halo titanium on this rifle and the M4. I have also used my Sandman K. All good options, the Halo titanium handles better with the weight. Just get an adjustable gas block and run the 11.5 it's the best of both worlds.

Edit: the Surefire would work good as well just going to be a bit heavier on the end of the gun.

 

Here is the rifle with suppressor next to a 14.5 M4 with a standard FH. 10.3 with a Sandman K etc. The Colt lower sits a little lower with the shorter stock.

 

Sent from my SM-G965U using Tapatalk

 

 

 

Super helpful, thanks! Gemtech folks have always been good dudes, have been fortunate to shoot with a few back in the day.

[apetrulis01]

How are the FBI Colt barrels (11.5)?