I'm trying to build my home defense gun to be a 300 blackout short barrel preferably 8.5-10in that can fit on a milspec lower with a folding brace and i will be suppressing at some point. I was originally going to go with the jakl platform from psa but I've seen a lot of different reviews some good some bad. I've also seen the Brownell brn180 and heard some good things about it, but not nearly as many reviews as the jakl despite it being much older. Curious to hear your guys opinions and experiences on these guns as wells as others that fit the criteria. Mostly just want to know what's going to be the most reliable, easiest to shoot in your opinion, and easiest to slap a suppressor and tune
- Thread starter sadhuahua
- Start date
I have these two to share that check most of those boxes.I cobbled together this piston Primary Weapons System Mk109 (9.75") .300 BO. The lower is a legacy Colt M4 Arkansas Rangers. Have used a variety of optics. I set up this KAC SR-30 SBR 9.5" in a similar fashion. The Law Tactical folder is pretty handy to allow both for backpack transport.
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Just get one of these, and rig it up like this... It's already got an adjustable gas piston system, and internal recoil springs, so no need for a buffer tube...
www.brownells.com 
www.brownells.com 
www.brownells.com 
Here's a pic of mine...
BROWNELLS BRN-180S™ GEN2 300 BLACKOUT 10" COMPLETE UPPER RECEIVER ASSEMBLY | Brownells
Check out the BROWNELLS available Online at Brownells Today and many more Rifle Receivers & Parts products are available in our Gun Parts Department.
www.brownells.com KNS PRECISION, INC. AR/MCX Picatinny Stock Adapter with Flange SKU: 923000071 | Brownells
Check out the KNS PRECISION, INC. AR/MCX Picatinny Stock Adapter with Flange SKU: 923000071 available Online at Brownells Today and many more Rifle Stocks & Parts products are available in our Gun Parts Department.
www.brownells.com JMAC CUSTOMS LLC 8-INCH RAISED ARM BAR WITH BRACE ADAPTER | Brownells
Check out the JMAC CUSTOMS LLC available Online at Brownells Today and many more Rifle Stocks & Parts products are available in our Gun Parts Department.
www.brownells.com Doublestar AR-15 Strongarm Pistol Brace
Doublestar AR-15 Strongarm Pistol Brace
www.joeboboutfitters.com
Here's a pic of mine...
I've been interested in the pws line but most are pretty expensive except the pro series but on the website I couldn't find any 300blk uppers so I was confused if they discontinued or what, have you had any issues with the pws, is it super finicky with certain loads or is it just pop the can on, flip the gas block and ur good to go
I believe there are a couple different piston makers
I like the brn/ar18 set up alot, is urs pretty reliable? How many rounds you got through it and any issues you've seen arise?Just get one of these, and rig it up like this... It's already got an adjustable gas piston system, and internal recoil springs, so no need for a buffer tube...
BROWNELLS BRN-180S™ GEN2 300 BLACKOUT 10" COMPLETE UPPER RECEIVER ASSEMBLY | Brownells
Check out the BROWNELLS available Online at Brownells Today and many more Rifle Receivers & Parts products are available in our Gun Parts Department.KNS PRECISION, INC. AR/MCX Picatinny Stock Adapter with Flange SKU: 923000071 | Brownells
Check out the KNS PRECISION, INC. AR/MCX Picatinny Stock Adapter with Flange SKU: 923000071 available Online at Brownells Today and many more Rifle Stocks & Parts products are available in our Gun Parts Department.JMAC CUSTOMS LLC 8-INCH RAISED ARM BAR WITH BRACE ADAPTER | Brownells
Check out the JMAC CUSTOMS LLC available Online at Brownells Today and many more Rifle Stocks & Parts products are available in our Gun Parts Department.Doublestar AR-15 Strongarm Pistol Brace
Doublestar AR-15 Strongarm Pistol Bracewww.joeboboutfitters.com
Here's a pic of mine...
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Ik, I'm trying to see people builds and they opinions on reliability from the reviews I've seen online alot of the piston set ups can be very hit or miss
I've put about 500 rounds of subs through mine (I load my own), and not a single issue so far. I have cans, so I don't shoot supersonic .300 BLK in anything. I'd say it's quite reliable. It's also a very clean shooting platform with a suppressor, thanks to the gas piston system. It's almost a mix between an AK and an AR, so the design is quite reliable. If you get one, and pull it apart, you'll see what i'm talking about. It was like they took the best of both platforms and meshed them together to make the BRN-180. It even uses an AR-style rotating bolt with locking lugs and M4 feed ramps. It's a pretty cool design.
POF has their P415 piston system and you can get just the 10.5" upper and use whatever lower you'd like although their lower is one of the best made. I have a 12.5 piston P415 in .223 and they're bomb proof. Can get the uppers from places like https://www.cflgunandtactical.com/ and others. It has a wider range of gas adjustments than my Sig piston and you can even turn the gas off completely. The POF is like hitting the easy button. Super accurate, soft-shooting and a tank. I really enjoy shooting it. It'll never be as light as a DI gun though.
My 300 black is a Sig Spear LT which, IMO, is a bit overpriced and the barrel's fast twist rate dictates you run just subs (but not plated like Berry's) or if you need supers, they need to be monolithic bullets if you're using a suppressor.
The Sig, with no buffer tube, is tiny when folded. If you're using the Sig stock or Kate Moss stock, when folded, it doesn't increase in thickness much and stays compact. Something like the Law Tactical folding stock adapter makes for a pretty thick package when folded and adds substantially to the length of pull. The adapter which slides into the back of the BCG is also heavy so there may be some tuning necessary. I ran a titanium BCG and any gains were negated by running the Law folder.
You can get just the Sig upper too but again, it's overpriced IMO. It'll work on any mil-spec lower with the Sig adapter. It eats everything I throw at it including Hornady's 190gr. Sub-X rounds. I've had issues with those bullets in other guns. The piston system is also very robust, and like the POF is duty capable.
My 300 black is a Sig Spear LT which, IMO, is a bit overpriced and the barrel's fast twist rate dictates you run just subs (but not plated like Berry's) or if you need supers, they need to be monolithic bullets if you're using a suppressor.
The Sig, with no buffer tube, is tiny when folded. If you're using the Sig stock or Kate Moss stock, when folded, it doesn't increase in thickness much and stays compact. Something like the Law Tactical folding stock adapter makes for a pretty thick package when folded and adds substantially to the length of pull. The adapter which slides into the back of the BCG is also heavy so there may be some tuning necessary. I ran a titanium BCG and any gains were negated by running the Law folder.
You can get just the Sig upper too but again, it's overpriced IMO. It'll work on any mil-spec lower with the Sig adapter. It eats everything I throw at it including Hornady's 190gr. Sub-X rounds. I've had issues with those bullets in other guns. The piston system is also very robust, and like the POF is duty capable.
I know pof they're 15 minutes from my house lol, have heard they're not very great guns though, I didn't even know they made a piston system
They're fantastic actually...I own two, the P415 and a Revolution DI in 308. Their piston system has been refined over the course of decades. I strongly suggest asking for a factory tour. It'll be worth it. Both of my POF's have been dead reliable and very accurate. I've had the 308 since 2019.
Here's a POF P415 meltdown video on YouTube.
Here's a POF P415 meltdown video on YouTube.
PWS is a great upper. They have a LEO/MIL discount or watch the Cannon Parts page for discounted items. Have not shot the .300 but love the 7.62 x 39 upper.
SLR makes a piston system?
Mistyped that. SA
ADJUSTABLE PISTON SYSTEMS
A Retrofit Kit for the AR-15 Platform with our Patented "Bleed Off"
suparms.com
