Combo: Rosco Manufacturing Bloodline 16″ M4 5.56 NATO Midlength + Kratos Gas Block

16″ M4 5.56 NATO Mid-Length Bloodline Barrel (Mid-Length): This 16″ M4 5.56 NATO Mid-Length barrel was designed around the USASOC specs for an Improved Upper Receiver Group with a little bit of the Rosco touch as well. The longer gas system allows for a smoother gas curve which leads to managed dwell times. This combo creates a great balance of speed and performance.

Our Rosco 5.56 (NATO) barrels are designed to meet the modern day carbine shooters requirements. We are a long way from our daddy’s “Sporter” AR, and those specs just won’t cut it anymore. From properly managed dwell times for SBR’s, to running Suppressed, or setting up a balanced patrol carbine we have incorporated your needs into our engineering. We have successfully accomplished this by picking the right twist rates, gas port diameters, and barrel materials according to the barrel we are making (not a lazy blanket method). We have also balanced input from our consumers and military end users in order to bring you the product you need, not just the one we want to sell you.

The Kratos Design Group Gas Block is CNC machined from precision ground 4140 steel bar stock. Featuring a .750 gas journal and a QPQ finish it is an incredibly robust low-profile gas block.

Several features throughout make the installation and maintenance easier.

• Located directly opposite the gas port hole is a small witness hole that you can use to verify proper alignment of the gas block over the barrel’s gas port. Jordan B. is responsible for providing Kratos Design Group with the idea for this hole. It’s a simple and effective way to visually confirm proper alignment.
• On the front of the gas block, there is a small hole that can be used to aid in the removal of the gas tube when needed for replacement or inspection. A 1/16″ punch can be used.
• Our gas block also features a built-in shelf to make drilling easier when pinning the gas block to the barrel. A ⅛” drill bit and ⅛” x ⅝” steel pin is recommended.
• Included are (3) 10-32 black oxide knurled set screws with a Rockwell hardness of C-45. We include an extra screw because they are easy to lose. Also in the package are (2) stainless steel gas tube coil pins.
  Set screw spacing: .420” Screw size: 10-32 (3/32” drive)
  Weight: 1.4oz

100% made in Texas from US-made steel.

Materials:

GAS BLOCK:

4140 Precision ground US steel. Heat treated and QPQ’d. Honed to 0.750″ID. Machined in TX.

SET SCREWS:

10-32 black oxide alloy steel knurled cup-point set screws.  Rockwell hardness of C-45. Allen key drive size: 3/32″. Made in the USA

GAS TUBE COIL PIN:

420 Stainless Steel coil pin. 550 pound breaking strength, Rockwell hardness of C46. Chamfered at both ends. Made in the USA

-Witness Hole to Verify Gas Port Alignment
-Machined Shelf for Pinning To Barrel
-Front of Gas Block Drilled For Gas Tube Removal
-4140 Steel
-QPQ & Heat Treated
-.750″ ID
– .420″ set screw spacing
-(3) Knurled Set Screws Included
-(2) Gas Tube Coil Pin Included
– Made in Texas
-Lifetime Warranty