AR build advice

[mills0713]

I'm in the process of building my first AR. I have a LMT Specwar upper with 12.5 barrel, mid gas. After reading the "The Gun Every American Should Own" thread, I feel like a made a good choice. The lower will be a stripped LMT Mars-L (I shoot lefty and like the ambi controls). This will be a SBR (no brace). I also have a CGS Helios DT supressor that will live on this rifle. I will be shooting handloaded 77tmk or 73 eld-m.

Question: What buffer system should I use for this setup (buffer and spring)? Because I shoot lefthanded, I want to minimize gas as much as possible without sacrificing reliability. Again, I will not be shooting unsuppressed.

There is a lot of info on Reddit. I trust the folks here more. I'm completely new to this world, so treat me as such.

Thanks in advance.

 

[Formidilosus]

I'm in the process of building my first AR. I have a LMT Specwar upper with 12.5 barrel, mid gas. After reading the "The Gun Every American Should Own" thread, I feel like a made a good choice. The lower will be a stripped LMT Mars-L (I shoot lefty and like the ambi controls). This will be a SBR (no brace). I also have a CGS Helios DT supressor that will live on this rifle. I will be shooting handloaded 77tmk or 73 eld-m.

Question: What buffer system should I use for this setup (buffer and spring)? Because I shoot lefthanded, I want to minimize gas as much as possible without sacrificing reliability. Again, I will not be shooting unsuppressed.

There is a lot of info on Reddit. I trust the folks here more. I'm completely new to this world, so treat me as such.

Thanks in advance.

That is an excellent upper/lower, and an excellent suppressor.

H2 buffer and spring. You will be over gassed suppressed as that upper was specd around absolute reliability at -30° F unsuppressed. However it reliably functions at 120° F unsuppressed with very hot ammo as well. If you want less gas, the best answer is a Black River Tactical reduced gas tube.

 

[mills0713]

That is an excellent upper/lower, and an excellent suppressor.

Yeah, I'm excited to put it all together.

H2 buffer and spring.

I'm assuming this would fit the bill:

https://geissele.com/premium-mil-spec-buffer-tube-assembly-with-super-42-h2-black.html

I'm open to other suggestions if you think there are better options.

If you want less gas, the best answer is a Black River Tactical reduced gas tube.

If I were to go this route, would you recommend the same buffer spring combo you gave above? If not, what would choose to go with the BRT gas tube?

Also, which LMT BCG would you recommend?

I don't like screwing around with different setups. I want to find something that works and just go with it.

I really appreciate the advice.

 

[Burnt Reynolds]

https://geissele.com/rifle-parts/lower-parts/springs.html

Super 42.

I run in my sbr's (11.3 & 14.5) as well as both of my 16" guns and it's absolutely a fantastic piece of kit. Their guide will tell you what you need for the 12.5".

Suppressed guns as well as unsuppressed - everything lands in a nice little pile at 3 o'clock.