7.5 AR config advice

[btmmiller]

Hey y'all, I wanted some advice from everyone here. I've been slowly getting the pieces together for an sbr build. While it was initially going to be a 10.5, I found out about NEA's new pdw stock and decided to go smaller. 7.5s are not as common, and I kinda want to do something off the beaten path. The PDW stock is neat, so I'm gonna get it when they release it later this year. Though this isn't going to be a doorkicking gun, I'd still like it to be as reliable as possible. I'm still debating between .300 and 5.56 but I would like to see if there is an "ideal" setup at this length with regard to buffer weight, gas port size, etc. I know what works will probably change between caliber, but info on both would be appreciated, if available. Also, I'll be running suppressed, whatever caliber I choose, would something like noveske's switchblock be useful at this length?

[Todd.K]

Suppressed: I would not consider less than 10" for 5.56, it will beat up the gun and silencer too much. 300 BLK is fine that short, and does not need an adjustable gas system. Consider handguard length plus room to attach the silencer, our 300 BLK barrel is 8.2" long to work with standard 7" handguards.

I have not seen the guts of the stock system you want. I think it comes with a special carrier, buffer and spring, so no way to know what it's designed to run for gas port size.

I would not use an unproven shortened spring system for serious use.

[btmmiller]

Suppressed: I would not consider less than 10" for 5.56, it will beat up the gun and silencer too much. 300 BLK is fine that short, and does not need an adjustable gas system. Consider handguard length plus room to attach the silencer, our 300 BLK barrel is 8.2" long to work with standard 7" handguards.

I have not seen the guts of the stock system you want. I think it comes with a special carrier, buffer and spring, so no way to know what it's designed to run for gas port size.

I would not use an unproven shortened spring system for serious use.

Interesting, for some reason I was under the impression that it used a pistol buffer tube. I must be mistaken. I'll probably wind up going blackout then, since 7" isn't a great idea in 5.56. Does the switchblock/smaller gas port not mitigate the abuse to the system in that length?

[Todd.K]

We don't make a Switchblock for the 7.5". Silencers are not generally warrantied below 10", and we would need to make a special rail just for it.

[btmmiller]

Good things to know. I seriously appreciate the info.