Springfield XD Forum banner
1 - 19 of 19 Posts

·
Registered
Joined
·
266 Posts
Discussion Starter · #1 ·
If you were wanting to make a sbr and do all the legal tax stamp stuff and proper forms what caliber would you prefer..
And why would you choose that caliber. Looking for some reason that you prefer one over the other.
 

·
Registered
Joined
·
29,864 Posts
.45acp, if I could find a lower.

9mm would be my next option; find a Colt 635 upper...
 

·
Registered
Joined
·
266 Posts
Discussion Starter · #4 ·
Honestly if I wanted to do a .45 I'd prob just buy a sbr vector. And 9mm interesting you would say that. Will think about that one. Kinda threw me off there lol.
 

·
Registered
Joined
·
3,851 Posts
300blk. The caliber was designed to be short barrel friendly. It also will take very kindly to a suppressor if you decide on one later.
It really depends on the length of my build. If I'm going sub 9 inch then 300 would have the best performance. If I'm going 11.5 MAYBE 10.5 then 223 is adequate. Although 11.5 would be ideal.

I guess it depends, so you want a rifle that will perform well ballistics wise or just something fun to shoot?

Doesn't matter if you're set on a rifle caliber, just register the lower and you can swap uppers. You'd be good for a variety of calibers 300, 223, 6.8 etc.
 

·
Registered
Joined
·
266 Posts
Discussion Starter · #6 ·
I was thinking azfist. Of a CHF daniel defense 10.3 300 blk if I did longer I'd end up going .223 I was thinking in .223 of like a 12.5 in dd. I want a spike tactical lower and then a upper later for the build.
 

·
Registered
Joined
·
3,851 Posts
11.5 offers the best ballistics/length compromise. You can find an article, on "why BCM chose the 11.5 for sbr.". Speaking of BCM, that would be my go to for an 11.5. If I was doing a 300 I'd probably go DD or Noveske assuming budget wasn't an issue.
But you can pick up a BCM complete upper 11.5 for around 500 with BCG. That's if you skip the handguard.

I'm building a "pistol" right now with those parts. Spikes punisher with red barn lpk and ALG trigger. CAC pistol buffer with SB15. With a BCM 11.5 upper. I'll likely pop off the A2 sight and throw on a vltor Casv and a noveske kx5. Would make a sweet little pistol.
 

·
Registered
Joined
·
266 Posts
Discussion Starter · #8 ·
Sounds a lot like something I want to build right now just trying to figure out laws and going about doing it correctly. I would love to see pics of it at some point in time.
 

·
Premium Member
Joined
·
15,438 Posts
Sounds a lot like something I want to build right now just trying to figure out laws and going about doing it correctly. I would love to see pics of it at some point in time.
Study local, state and Federal laws... Look into a Gun Trust

There are a lot of good information on this site if you search it along with AR15.com. Do some google searches. I can tell you what is needed but unless you understand the scope of what you are getting into, it will not matter.

@John A. might be willing to help out. He is a wealth of NFA knowledge, but there is a lot the goes into owning NFA weapons

NFA Talk XDTalk Forums
 

·
Registered
Joined
·
266 Posts
Discussion Starter · #10 ·
Yea I read that you have to engrave your name on the sbr registered lower along with city state or trust name. We just pass owning sbr in Washington state last February
 

·
Registered
Joined
·
5,759 Posts
Best is relative to what you want to do with it. With as little information you provided in the OP, there is no way to be able to give you a really good answer.

While it has been noted that the 300 blackout does do well in + 8" barrels, that is not to say that many other weapons (calibers) do poorly either.

Just for the record, pistol calibers like 9mm and 45acp, 38/357, 40 S&W 10mm, etc also will do well from an even shorter (than 8") barrel and were actually designed to be fired from barrels shorter than 6 inches and when fired through longer barrels actually exceed the usual manufacturers velocity and "power rating" and increase in velocity and ft pounds, etc.

As for suppression, 4 of the 6 handgun calibers I mentioned above all have subsonic loads for them. Actually, the 38 Special, are all subsonic, even the +P, though I don't know any AR that are chambered in 38357, but they could be with a few design changes, but I digress. There are however 9mm, 40 S&W, 10mm and 45acp AR's out there.

AAC/Remington has spent years trying to push the 300 blackout (which they didn't design and mostly pirated anyway but is a whole different topic altogether), but in their marketing push, they only mentioned the few calibers that the blackout does perform slightly better than.

Do you remember anyone from AAC comparing the blackout to 10mm or even 45acp for close quarters tests? I don't. And with reason.

True that supersonic blackout does perform better at longer ranges than a handgun caliber, but if you're going to be building an sbr, I can only assume that it's for shorter ranges where an SBR would be the obvious better choice. Sniping targets at longer ranges simply dictate different weapons and choices.

So, what are your expectations and purpose/reason for considering building an SBR? What do you want to do with it and what do you want it to do?
 

·
Registered
Joined
·
19,987 Posts
Why hinder yourself with the AR platform for a pistol caliber gun at all? I'd get a Tommy Gun or Kriss if I wanted a 45 sbr.

I've gotta think a supersonic 300blk would trounce a 45 at close range with a decently designed bullet. It is only when subsonic that the 45 wins.
Ballistics by the inch
looks like out of an 9" barrel, the 45acp peaks at 700ft-lbs with the fastest +P
The 300blk supersonics are over 1100ft-lbs from the same length
300 AAC Blackout 7.62 35mm - Wikipedia the free encyclopedia
 

·
Registered
Joined
·
5,759 Posts
Why hinder yourself with the AR platform for a pistol caliber gun at all?
If that is a question for me, I don't own a 9mm AR.

I covered my pistol caliber bases with an sbr MP5K and I also have a f/a Ingram M10/9 that has a Lage upper and 8.5" barrel.

Both of which were originally designed to use 9mm.

Many Ingrams can use both 45acp and 9mm by simply replacing the mags and complete upper much like AR's.

I also have a full size semi auto uzi that I adore.

 
  • Like
Reactions: dillon91

·
Registered
Joined
·
266 Posts
Discussion Starter · #15 ·
mp is so sick looking dang I would totally rock one of those bad boys. your other ones are also nice. I can tell you dig NFA weapons
 

·
Registered
Joined
·
5,759 Posts
I do enjoy the NFA aspect of collecting.

The MP5 is alright, but they can be very particular.

To be honest, it's not one of my first grabs.
 

·
Registered
Joined
·
266 Posts
Discussion Starter · #17 ·
Honestly I would love to have 1/4th of the rifles you have showed me in pictures today at my disposal :p.
 

·
Registered
Joined
·
47 Posts
I wouldn't bother with 300BLK unless you are (1) reloading, and (2) getting a suppressor. If you are doing both, 300BLK is an awesome round. If you're not doing either, it's very expensive and you aren't really getting the benefit of the design; in this case, I'd opt for 5.56 (for defensive use) or .22lr (for plinking). Can always build a 300BLK upper for your lower sometime down the road when you're ready to take full advantage of the caliber.
 
1 - 19 of 19 Posts
Top