DIAMONDBACK DB9-RBB
A modern 9mmp Ar-type semi-auto carbine
DIAMONDBAC K IS A US company that started out in 1989 in a small workshop with three employees. It has since expanded into a factory with over 200 workers, designing, manufacturing, testing , and delivering a range of semi-auto rifle sandp olymer-frame pistols.
Firearm production began only in 2009 with the establishment of Diamondback Firearms, initially delivering reliable, precision machined components to distributors. However, as their manufacturing capacity developed, they were able to produce micro-compact .380 Auto pistols. Further expansion brought them to their present output which includes the DB9R Ar-carautos bine shown here, as well as semi in centre-fire rifle calibres and various pistols.
The DB9R is an Ar-type rifle chambered in 9mmp, meaning it can use a blowback system (not gas-operated as in traditional ARS), which helps to keep
the weight down to 3kg, should ensure that the rifle stays cleaner for longer, and helps to reduce recoil.
The 16-inch barrel is from 4150 Crmov steel and has a black nitride finish. Barrel twist, as in the case of most 9mmp pistols, is 1:10, which means it will stabilize almost all 9mmp ammunition. A screw-on A2 flash hider comes standard.
The bolt carrier is also black nitride – necessarily beefy and heavy, to accommodate the blowback system. On firing, pressure from the expanding gas pushes the bolt rearwards to eject the spent case and cock the striker, whereupon a spring in the stock forces the bolt forward, stripping a fresh round from the magazine, pushing it into battery.
The upper and lower receiver is of forged 7075 T-6 aluminium. The 15-inch long handguard has Keymod interfaces on the sides and underside, and a Picatinny rail on top for fitting attachments. The receiver has an integral rail. The pistol grip is a standard A2, and the adjustable polymer UTG Pro stock has a rubber butt-pad plus an integral sling loop and QD sling swivel housing usable by left or right-handed shooters. The adjustable stock can alter the carbine’s overall length from 35¼ inches to 32 inches. Both grip and stock are replaceable with a plethora of after-market alternatives.
The rifle came with a 32-round Glock-type Promag magazine with witness holes for 31 rounds, but any double stack Glock mag should work as well.
The smooth trigger is a standard Ar-type, but various after-market replacements are available. The single stage pull has some creep but broke cleanly and is more than suitable for semi-auto use.
The two-position safety is easily operated with the right-hand thumb – push downward to the FIRE position. The magazine release is within reach of
the trigger finger, being a flat lever that slots into the cut-out of the magazine. The bolt release lever is on the left-hand side of the lower receiver and is easily worked with the left hand (right-handed shooters).
The receiver was purpose-built for the 9mm cartridge, hence has a small, bevelled ejection port. There is no ejection port cover. The upper receiver has a raised brass deflector behind the ejection port, but there is no forward-assist to ram a cartridge home. However, there is a depression cut into the right side of the bolt, visible at the rear end of the ejection port, which can be used to thumb-thrust the bolt forward. The ejector is affixed to the lower receiver.
In addition, the mag-well is wide and deeply flared to facilitate quick mag changes and I found it almost impossible to fumble a mag change when shooting against time.
Bullet Corp (124gr 1 099fps), Josyd lead bullets (115gr RN 1 106fps). The handloads are my normal pistol practice rounds loaded to very moderate velocities. The 16-inch barrel increased factory ammo velocities by about 250fps compared to those from a compact pistol. A 124gr 9mm bullet travelling at 1 250fps and faster is replicating .357 Magnum ballistics in terms of muzzle energy, which should make the carbine a very effective defensive weapon for farmers, provided strong bullets like Hornady’s Critical Duty or similar are used. If you plan to fire many shots per shooting session I’d avoid cast bullets as excessive bore-leading might raise pressures. However, powder-coated or plated lead bullets should not cause this problem.
I mounted a low magnification scope and used a rest for testing the DB9R for accuracy at 35m. The Fiocchi ammo printed into 1.039 inches and the S&B factory ammo delivered a 1.12-inch group. The lower velocity handloads all printed less than 1.5 inches.
Using a red dot sight at 35m, I fired another 30 shots as fast as I could get the sight back on target and pull the trigger. Twenty-five bullets grouped roughly into a 3-inch circle on the paper target, while the other five opened up the ‘group’ to 4.75 inches. I successfully engaged steel plates out to 75m. At 100m, bullets will theoretically drop about 12 inches with retained velocity between 900 and 1 000fps.
RECOIL IS MINIMAL; the carbine is ideal for recoil-sensitive shooters. I fired just over 250 shots and experienced two malfunctions, shots 3 and 4, with the bolt not returning to battery. I disassembled the rifle and sparingly oiled the bolt. Thereafter the little carbine consumed the rest of the mixed bag of rounds without hiccup. The mag dropped to the ground every time I pressed the mag release.
I found the lightweight carbine a pleasure to shoot, easy to operate, accurate and utterly reliable. It’s ideal for 3-Gun sport shooting, plinking and self-defence. The fact that it’s chambered in 9mmp is a plus: ammunition is more affordable than rifle calibres, easy to reload, components are freely available, and if you own a Glock, well, then you have spare magazines. Having a carbine and a pistol in the same calibre means you reload for only one calibre and can use the same bullets and powder charge for both. Also, the carbine allows you to train and familiarise yourself with the Ar-platform on the cheap, should you later upgrade to a rifle cartridge. You can customize the carbine to your taste as accessories are freely available and these can later be transferred to any other similar rifle.
Decades ago many shooters owned a revolver for self-defence and chose a lever-action in the same calibre. The DB9R is a natural evolution, complementing the modern pistol. I found it for sale online for just under R30 000.■