Question on AR-15 Pistol Build - Buffer and Arm Brace Question

[Longshot231]

I'm exploring all options for an AR-15 build, except for caliber. It will be chambered in 5.56 MM with a barrel length about about 10-12 inches. I'm not sure whether to go with a direct impingement or piston driven upper. It will be suppressed with an OSS can.

With that can, I'm not worried about blow back as it has performed as advertised on other gas guns. Anyway that might be too much information but will throw it out there anyway.

However, I'm not sure what I want for the arm brace, buffer tube and buffer. All options on that part of the pistol are on the table.

Any thoughts or suggestions would be greatly appreciated. Thanks in advance.

 

[redneckbmxer24]

Direct gas because it’s more reliable and no issues with carrier tilt.

LMT enhanced buffer tube ALWAYS. They’re a little tighter fitting and properly fitting so braces and stocks don’t wiggle around. SBA3 is my preferred brace.

 

[Longshot231]

Direct gas because it’s more reliable and no issues with carrier tilt.

LMT enhanced buffer tube ALWAYS. They’re a little tighter fitting and properly fitting so braces and stocks don’t wiggle around. SBA3 is my preferred brace.

Carrier tilt? Interesting. Never heard of it before. What happens with carrier tilt? Is it solely a problem with AR pistols or SBRs?

 

[redneckbmxer24]

The carrier tilts down at the back when cycling. It’s a problem with all AR15’s with pistons because it wasn’t designed to work that way and like with most retrofitted stuff it rarely works correctly and is half assed. Just like sticking 9mm in an AR15 platform.

There’s better ways to deal with gas with a can that won’t hurt the reliability or effect function. Adjustable gas blocks, longer gas systems, LMT enhanced BCG, etc.

 

[Longshot231]

The carrier tilts down at the back when cycling. It’s a problem with all AR15’s with pistons because it wasn’t designed to work that way and like with most retrofitted stuff it rarely works correctly and is half assed. Just like sticking 9mm in an AR15 platform.

There’s better ways to deal with gas with a can that won’t hurt the reliability or effect function. Adjustable gas blocks, longer gas systems, LMT enhanced BCG, etc.

Thanks. That's good to know. All that I have ever had on the gas guns were OSS suppressors. I really like their flow through technology. My ARs don't get any dirtier and I don't have a bunch of gas, gunk, grease or anything else blowing back in my face.

I get more blow back from my suppressed 9mm handguns than any of my suppressed AR-15s. However, I digress.

I was looking at the LMT buffer tubes but could not find anything labled "enhanced."

I'm basically stuck with what arm brace / extension tube as well as weight of the buffer to go with. I read that an AR-15 pistol needs a heavier buffer.

If I could find a complete buffer/brace assembly, that would make my shopping much easier.

 

[redneckbmxer24]

Thanks. That's good to know. All that I have ever had on the gas guns were OSS suppressors. I really like their flow through technology. My ARs don't get any dirtier and I don't have a bunch of gas, gunk, grease or anything else blowing back in my face.

I get more blow back from my suppressed 9mm handguns than any of my suppressed AR-15s. However, I digress.

I was looking at the LMT buffer tubes but could not find anything labled "enhanced."

I'm basically stuck with what arm brace / extension tube as well as weight of the buffer to go with. I read that an AR-15 pistol needs a heavier buffer.

If I could find a complete buffer/brace assembly, that would make my shopping much easier.

All of the LMT buffer tubes are the enhanced ones. They just have a 556 and 762 version, you want the 556.

For 10.5-12.5” H2 if you want it to definitely run suppressed and unsuppressed and H3 if you will be running suppressed all the time. If you do a adjustable gas block I’d just go with the H2 and tube it that way and just know which setting for which. That’s ideal.

 

[Asiparks]

Are we in 2008 ? Carrier tilt was a marginal issue at best back then, if you had some drunken monkey made aftermarket set up and after thousands of rounds.
It's a non issue.
Go DI or Piston, I have both -in the real world the difference is tomato: tomato.
Go SBA for the brace, I've got 3's and a 4, much prefer the 3, YMMV. It comes complete with a perfectly good buffer tube.

 

[ramblr72]

It comes complete with a perfectly good buffer tube.

This. The only reason I would go with a different tube is to run VLTOR A5 setup.

 

[AMGtuned]

Brace is SBA3. I have zero complaints with mine. Lockup is tight, swivels work well, but a 1.25" swivel fits tight in that spot. Get the split fix from 3 Wiseman company. I run 10.5" barrels, 1:7 twist. Cycles all the bulk trash 55/62gr, hand loads from my 16", some 77gr stuff, etc.; using carbine, h1, and h2. H2 is the most comfortable with non adjustable Aero gas block. With adjustable, all of them still work for me. Good luck

 

[Longshot231]

There is an LGS here in town that builds uppers. I know I could do that myself but don't have the patience for that part of the gun. Besides, they only charge $50 for assembly fee.

I ordered and customized upper with 10.5" barrel 1:7 twist with 5.56 chamber. The M-lock hand guard is 10" long. Standard receiver with forward assist. I'm getting a BCG with nickle boron coating and Radian Raptor silencer optimized charging handle. Almost forgot, plain-Jane dust cover.

Keep those suggestions coming. Everyone is giving me some good information.

 

[abentley324]

I'm exploring all options for an AR-15 build, except for caliber. It will be chambered in 5.56 MM with a barrel length about about 10-12 inches. I'm not sure whether to go with a direct impingement or piston driven upper. It will be suppressed with an OSS can.

With that can, I'm not worried about blow back as it has performed as advertised on other gas guns. Anyway that might be too much information but will throw it out there anyway.

However, I'm not sure what I want for the arm brace, buffer tube and buffer. All options on that part of the pistol are on the table.

Any thoughts or suggestions would be greatly appreciated. Thanks in advance.

You’ll love this combo as I’ve fallen in love with mine. Vltor A5 with a pistol brace. Softest shooting most reliable AR I’ve ever had

 

[Asiparks]

Sounds like a good build. The only part I'd maybe change would be the Raptor CH. I got one to replace the Mil Spec one on a 10.5" DD pistol that I shoot suppressed: it wasn't as gas blocking as my PRi Gas-buster Ambi CH, so I flogged it and got another ( cheaper) PRi.
If your having someone build your upper for you, ask if he can do the silicone sealant mod on the CH ( youtube it). I've found it effective.

 

[Longshot231]

Sounds like a good build. The only part I'd maybe change would be the Raptor CH. I got one to replace the Mil Spec one on a 10.5" DD pistol that I shoot suppressed: it wasn't as gas blocking as my PRi Gas-buster Ambi CH, so I flogged it and got another ( cheaper) PRi.
If your having someone build your upper for you, ask if he can do the silicone sealant mod on the CH ( youtube it). I've found it effective.

Silicone mod; do you mean like this?

 

[Asiparks]

yup. just like that. Thatt's actually one of the most comprehensive ones I've seen. Nice find.

A PS on the SBA3 brace- there are a ton of $30 fake ones out there on Ebay/etsy, but I've not seen one that comes complete with a buffer tube.

 

[Longshot231]

I’m considering getting the Maxim CQB pistol brace with the heavy JP silent captured buffer spring.

The only drawback is the cost but I’m not married.

Any thoughts on that combination?

 

[Darqusoull13]

I’m considering getting the Maxim CQB pistol brace with the heavy JP silent captured buffer spring.

The only drawback is the cost but I’m not married.

Any thoughts on that combination?

Just make sure you get the shortened Maxim size silent captured spring system.

I could never get used to shooting the Maxims but I have some friends that love them because of how compact they get. I went with the SBA3 for my "pistols" until they became rifles after the government blessed me with more theft via Form1's.

 

[Longshot231]

Just make sure you get the shortened Maxim size silent captured spring system.

I could never get used to shooting the Maxims but I have some friends that love them because of how compact they get. I went with the SBA3 for my "pistols" until they became rifles after the government blessed me with more theft via Form1's.

I did order the silent captured spring system in the heavy configuration. They told me that JP recommends that for barrels under 16 inches in 5.56 MM that a heavy buffer should be used.

I got everything else ordered except for optics. Here's a list of what I got ordered so far besides the upper and the stripped lower.

-Armaspec Gun Builders Lower Parts Kit
-HiperFire Eclipse Trigger
-Ergo Flat Top Deluxe Zero Angle Grip
-MagPul BAD Lever
-Maxim CQB Pistol PDW brace with heavy silent captured spring system

For now, I will use some iron sights that I have in the parts box until I figure out what I want for optics. Since it is a pistol, I think I'll want something with zero magnification and clip on night/thermal vision later on. Suggestions gratefully accepted.

Thanks in advance.