SBR dilemma

brycewise · July 24, 2014, 08:54 PM

I was hoping for some helpful thoughts and advice for a project I have been contemplating. I would like to build a SBR with folding stock set up for a overall length of less the 20inches, I have been looking at 5.56 options but the blast and power loss seem to be at the point of diminishing returns.

I also was looking at the mini draco but haven't found any ballistics report from a 7.75 inch ak barrel.
Would the better comprise be a pistol or rifle caliber?
If a rifle caliber 5.56, 6.8 7.62....

I would like to keep this under $1000 for the rifle (not including tax stamp, ammo mags etc.)

Theohazard · July 25, 2014, 01:14 PM

Are you ruling out the AR-15 platform because the stock doesn't fold? I know some companies make buffer tubes that fold, but I don't know much about how they work. But if you're willing to go with an AR, then 300 Blackout is one of the best short-barrel rifle cartridges out there. It performs great from even an 8" barrel.

skizzums · July 25, 2014, 06:08 PM

300 blk all the way, especially if you wanna stay in that price range, ar folding stocks are pretty cheap

if you wanna be able to use the gun with the stock folded, build a 300blk pistol driven, thatd be a sweet rifle

tirod · August 25, 2014, 12:54 PM

.300 BO or 6.8 would both fill the bill. They have excellent short barrel ballistics.

The LAW folding stock adaptor will get the tube to fold, with a wrist brace it's now pretty common on AR pistol builds. Arfcom has a number of pics and threads on it. A piston build would allow it to actually fire folded for more than one round, but nobody is asserting there is any reasonable accuracy in the attempt.

A linear compensator is the muzzle device of choice, it's easily noted they have no side porting at all, muzzle blast is directed forward away from the shooter. It reduces the perceived noise at the shooters ear.

Under $1000 will be a challenge. Piston doesn't support it much. The LAW adapter is over $200 alone, and the wrist brace over $100 at best on ebay. A finished lower is cheaper than an 80%, and blem parts as available help cut costs. The .300BO or 6.8 barrel won't be found dirt cheap, the .300 might have an edge for bolts and mags. Not spending money on trendy free floats will help, and avoiding the expense of both a red dot and clamp on BUIS will help. Regardless it's a short barreled upper, it would be a hard price point to accomplish unless it's shopped a lot. Keeping an eye on Palmetto for holiday bargains is likely to net some, but it takes a lot of time looking around to accomplish.

It goes to the SB15 brace that a lot of new builders are interested - it relieves us of the requirement to fill out the ATF forms, long wait times, and $200, which can go to the costs of the build, not administrative fees.

Coach Z · August 25, 2014, 10:51 PM

What about a 10mm glock in one of the many SBR chassis for the full size glock platform? As long as you're going that short might as well start thinking pistol caliber and 10mm is arguably the top of that heap.

Hera and Roni are the two that come to mind straight away, Mako also makes a stock

Lark · August 25, 2014, 11:24 PM

458 socom. Probably the most powerful cartridge you can load in an AR-15 magazine. 600 grain bullets at 1050 fps are useful for hunting also.

Ranb

July 24, 2014, 08:54 PM	#1
brycewise Member Join Date: July 2, 2014 Posts: 23	SBR dilemma I was hoping for some helpful thoughts and advice for a project I have been contemplating. I would like to build a SBR with folding stock set up for a overall length of less the 20inches, I have been looking at 5.56 options but the blast and power loss seem to be at the point of diminishing returns. I also was looking at the mini draco but haven't found any ballistics report from a 7.75 inch ak barrel. Would the better comprise be a pistol or rifle caliber? If a rifle caliber 5.56, 6.8 7.62.... I would like to keep this under $1000 for the rifle (not including tax stamp, ammo mags etc.)

July 25, 2014, 01:14 PM	#2
Theohazard Senior Member Join Date: April 19, 2012 Location: Western PA Posts: 3,829	Are you ruling out the AR-15 platform because the stock doesn't fold? I know some companies make buffer tubes that fold, but I don't know much about how they work. But if you're willing to go with an AR, then 300 Blackout is one of the best short-barrel rifle cartridges out there. It performs great from even an 8" barrel. __________________ 0331: "Accuracy by volume."

July 25, 2014, 06:08 PM	#3
skizzums Senior Member Join Date: July 1, 2013 Location: Douglasville, Ga Posts: 4,615	300 blk all the way, especially if you wanna stay in that price range, ar folding stocks are pretty cheap if you wanna be able to use the gun with the stock folded, build a 300blk pistol driven, thatd be a sweet rifle __________________ My head is bloody, but unbowed

August 25, 2014, 10:51 PM	#5
Coach Z Senior Member Join Date: February 18, 2011 Location: RI Posts: 795	What about a 10mm glock in one of the many SBR chassis for the full size glock platform? As long as you're going that short might as well start thinking pistol caliber and 10mm is arguably the top of that heap. Hera and Roni are the two that come to mind straight away, Mako also makes a stock __________________ Love my guns

August 25, 2014, 11:24 PM	#6
Lark Senior Member Join Date: November 28, 2012 Location: Western WA Posts: 144	458 socom. Probably the most powerful cartridge you can load in an AR-15 magazine. 600 grain bullets at 1050 fps are useful for hunting also. Ranb __________________ Lark is free!

August 25, 2014, 12:54 PM	#4
tirod Junior member Join Date: January 21, 2009 Posts: 1,672	.300 BO or 6.8 would both fill the bill. They have excellent short barrel ballistics. The LAW folding stock adaptor will get the tube to fold, with a wrist brace it's now pretty common on AR pistol builds. Arfcom has a number of pics and threads on it. A piston build would allow it to actually fire folded for more than one round, but nobody is asserting there is any reasonable accuracy in the attempt. A linear compensator is the muzzle device of choice, it's easily noted they have no side porting at all, muzzle blast is directed forward away from the shooter. It reduces the perceived noise at the shooters ear. Under $1000 will be a challenge. Piston doesn't support it much. The LAW adapter is over $200 alone, and the wrist brace over $100 at best on ebay. A finished lower is cheaper than an 80%, and blem parts as available help cut costs. The .300BO or 6.8 barrel won't be found dirt cheap, the .300 might have an edge for bolts and mags. Not spending money on trendy free floats will help, and avoiding the expense of both a red dot and clamp on BUIS will help. Regardless it's a short barreled upper, it would be a hard price point to accomplish unless it's shopped a lot. Keeping an eye on Palmetto for holiday bargains is likely to net some, but it takes a lot of time looking around to accomplish. It goes to the SB15 brace that a lot of new builders are interested - it relieves us of the requirement to fill out the ATF forms, long wait times, and $200, which can go to the costs of the build, not administrative fees.