Quote Originally Posted by OTShooter View Post
I just stumbled on this thread, and I think I have some useful experience to share.

First, my first SBR was a 9mm AR. NOT a dedicated 9mm, but the Form 1 configuration is in 9mm with a 10" barrel. I have a Rock River magazine block, and it runs all my various magazines flawlessly. That's because the block is adjustable, not because Colt-style 9mm AR magazines are all perfect, but because I can set the mag block where it needs to be to run all my mags.

So point #1 with 9mm ARs is that magazines make a huge difference. And I think magazine selection should drive what sort of 9mm AR one decides on.

Which leads to this: My second SBR is a QC10 GSF lower, that I currently run with the 10" 9mm upper. I will eventually get a .40 S&W upper for it - that was the ultimate purpose in going with this particular dedicated design: to get a .40 S&W carbine/SBR for all forms of "social interaction."

My first 300 Blackout gun is an 8" upper that runs on my first SBR lower. Like a top, I might add. I think 300 Blackout almost demands handloading, at least as of now, but it's a very flexible round. I don't have a .30 can at the moment, but that's a definite plan. It's a blast to shoot unsuppressed and supersonic, and I've developed some surprisingly accurate loads with 110gr, 120gr and 150gr bullets.

Point #1 for 300 Blackout is that it's all about the ammo. If you don't handload, you're at the mercy of the ammo makers. If you do, it's all about taking your time and developing loads that do what you want them to do.

With both of my pistol caliber setups and my Blackout setup, all the ergonomics are exactly the same as with any standard AR, and yes I use exactly the same buffer and spring for the 9mms and for the Blackout.

Sig's MPX has me salivating, but for now I think I will have to hold off and just watch the show. I hope to have an MP5 clone before I invest in a Sig. More affordable and I actually have a little trigger time with an MP5...
Thanks for your post. I am a big reloader so that's not a problem. For me there are pros and cons of each kind of setup. A .300 BLK is good because I have an SBR'ed lower already. It's not good because I don't have a can for it yet, however I do have the option of using my 9mm can on it just so long as I shoot all subs all the time. The cost to shoot it though is higher and it means while I am trying to get out of so many calibers that I will be adding a caliber.

A dedicated 9mm SBR is probably the best option for me but so far I haven't found what just turns me on in that area.

A couple of points of my own... 1) I am definitely gonna get deeper into the NFA game. There is just no getting around it. That applies to more SBR's and more suppressors. 2) I am not very good at buying blindly. You can pretty much ask anybody here about that one. But before I buy and commit to an SBR I think I need to shoot em before I buy em. That's kind of difficult because I have been to an actual public gun range I think once or maybe twice in 2 or 3 years. The last time I actually went to a public range was about 2 years back. Basically I need to drag my ass down to Houston somewhere and just rent the guns and do a side by side.

On top of all that I have to just make priorities about all the stuff I want. As of right now I am leaning to getting a nice long range precision rifle first because it is something I like to do a whole lot and it's a 'hole' in my firearms line up. If I can ever get my butt back to working full time it will make a whole lot of this stuff easier. Basically there is a lot of stuff not related to guns at all that's holding me up right now.