Rosco Manufacturing Purebred 10.5" 300 BLK Heavy 1:7 Twist Pistol Stainless Barrel - PB-105-HB-300BLK-7-P
Out of stock
Purebred 10.5 300 Blackout Barrel: This Rosco Purebred 10.5 300 Blackout Barrel was designed for SBR/ Pistol use in conjunction with suppressors. The 10.5” Rosco barrel was made to be a direct precision replacement for any MK 18 platforms that are currently in 5.56 NATO. The 10.5 barrel is also perfect for carbines which require a slightly longer rail in order to run PEQ-15’s, D-BAL (series), or any laser aiming devices comfortably. ALL NFA RULES APPLY!
Rosco Manufacturing’s Purebred series is a testament to precision and quality manufacturing. We took a step back to see how we could create a barrel line that would be a culmination of all the lessons learned through years of making barrels for several OEM’s. The result is a barrel that will produce results out of the box for any shooter that is looking to take their skills above and beyond. All of our Purebred barrels are made from scratch in our Rhode Island facility and start life as a blank piece of 416R stainless steel.
Aside from making our own barrel blanks, and barrel extensions, we also hold ourselves to the most stringent quality standards. This is the only way that we can make sure that we are producing a product that will perform time after time under the demanding of situations. We are setting out to re-define the rules and we plan on letting our work do the talking
Specifications:
- Barrel Length: 10.5
- Barrel Weight: 21.09 oz
- Barrel Material: 416 R
- Barrel Caliber: 300 BLK
- Barrel Profile: Heavy
- Twist: 1:7
- Barrel Thread: 5/8 x 24
- Barrel Gas Block Size: 0.750
- Gas System Length: Pistol
- Barrel Crown: Step Crown
- Barrel Finish: 80 Grit Bead Blast
- Barrel Extension Finish: Nickel Boron
| Weight | 20.96 oz |
|---|---|
| Dimensions | 12.5 × 3 × 3 in |
| Finish | Stainless |
| Barrel Profile | Heavy |
| Cartridge Compatibility | 300 BLK |
| Gas Block Journal | 0.75 |
| Barrel Length | 10.5 |
| Gas System Length | Pistol |
| Platform | AR-15 |
| Twist Rate | 1:8 |
| Muzzle Thread Pattern | 5/8×24 |
| MPN | PB-105-HB-300BLK-7-P |
| UPC | 181969500289 |
Compliance
NFA (National Firearms Act) compliance is crucial for legal ownership and transfer of regulated firearms and accessories like short-barreled rifles, suppressors, and certain types of ammunition, ensuring adherence to federal regulations to avoid legal penalties and ensure responsible firearm ownership.
Customer Reviews
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United States
Works great
This is my first complete upper build and the barrel is very accurate. I did have trouble with subs cycling. I went thru the complete gas system and buffer system but here is where I ended up. I'm running a reduced yellow sprinco spring with an H1 buffer I think it's 3.2oz. I'm shooting 200 gr phantom defense with the makers bullets. (Very good round) To get them to run I had to drill the gas port from .086 to .094. this is after I bore scoped to verify gas block alignment. (Note that the dimple was perfectly aligned and the gas block sits tight to the edge of the shoulder. The gas tube should align with the barrel markings) after hours of research on the forums I found a good gas port size chart and for 10.5" it gave .093" to .105" so I went small. I drilled it with a lil oil and a cordless drill I wet brushes after and wet and dry patched afterwards. I did another bore scope and the hole was cleaner after I drilled than before. I shot it today and it cycles perfectly with both subs and supers locking back on last round. I'm using a B&T low back pressure can shooting both subx 194gr and 200gr slowpapi rounds both loaded by phantom and 110 gr Barnes and AAC Blacktop I had zero POI shift or accuracy difference from before I drilled to after. This barrel is 1.5 MOA with the supers and 1 3/4 MOA with subs using a 3X prism from primary arms. So in conclusion I am happy with this barrel and if I bought another I would just drill it from the start and it is perfect
USRosco purebred 10.5” 300 blackout
The barrel fit and finish are very nice, haven’t got a chance to send any rounds through it yet but I am expecting nice grouping and life from the barrel!
