The ACT–99c is a collaborative effort between three small up and coming defense companies: Irish arms manufacturer Castle Arms, American innovative magazine, ammunition, accessories and energy weapons developer Cheyenne Defense Research and Dutch digital sight company VanDan Combat Optics. The first concept for the weapon in 2023 was developed by Castle Arms in response to NATO specifications for a universal rifle system. Although the NATO initiative eventually failed due to countries being unwilling to give up their issue weapons, the Israeli Defense Force placed an order with Castle Arms for 10,000 weapons, followed almost immediately by contracts from the United States Marine Corps and the FBI. At this point Cheyenne Defense and VDCO were brought on board because the FBI increased the original specifications to include an adaptive digital combat sight, and the Marine Corps demanded a version which could fire armor piercing and sabot discarding rounds from a lightweight high-capacity magazine.
In the field, Israeli and US Marine infantry were very impressed with the weapon. It was extremely reliable due to its short stroke piston system and caseless design both of which prevented jams from either carbon fouling or external materials entering the weapon. It also proved to have stopping power unsurpassed for an intermediate caliber weapon, when loaded with armor piercing rounds it has been known to effectively penetrate both ceramic plated body armor and some light armored vehicles. Also, because of its compact case-less ammunition and use of polymer magazines, troops could carry up to 35% more ammunition than previously, and thanks to its use of quad stack 50 round magazines needed to be reloaded less often. Also thanks to its caseless ammunition the weapon is completely ambidextrous, a trait unseen in bullpup weapons firing conventional ammo. But what all users of the weapon praised most was its adaptability; the base unit could be modified to perform in the roles of either an assault rifle, designated marksman rifle, light machine gun or personal defense weapon, which meant that any soldier on the battlefield could share his ammunition with any other, regardless of what role either of them were assigned to. This was also considered a blessing by logistics personnel, who now only had to manage one weapon system instead of four, and only one caliber of ammunition.
Info Sheet, Castle Arms Ltd. ACT-99c infantry weapon system.
Length (base unit):19 inches (PDW): 27 inches (carbine): 34 inches (DMR/LMG): 54 inches.
Height (base unit): 7 inches ( base unit with built-in SmartSight): 9 inches
Thickness (base unit): 2 inches (base unit, charging handle included): 4 inches
Weight: 4.34 pounds
Manufactured mostly from high grade polymer composites, with as little metal as possible. The bolt carrier, gas piston, gas block and firing chamber shield plate are made of boron-carbide ceramic, capable of withstanding extremely high temperatures and holding up against an AK-47 round from 3 feet away. Metal parts include: barrel, RIS rails, bolt, firing pin, flash suppressor, assorted retaining pins and fire control group.
Magazine and Caliber
Magazine: Standard issue: Cheyenne Defense Research QSCM magazine.
Length: 3.5 inches.
Height: 6.8 inches.
Thickness ( at thickest point): 1.75 inches (at thinnest point): .75 inches.
Capacity: 50 rounds
Feed System: quad-stack casket
LMG configuration: Cheyenne Defense Research QSDM high-capacity drum
Length: 3.5 inches.
Height: 11.8 inches.
Thickness ( at thickest point): 10 inches (at thinnest point): .75 inches.
Capacity: 200 rounds
Feed System: quad-stack drum
Caliber: 6.5x 45 mm CMPR
Total Length: 45 mm
Bullet Length: 20 mm
Propellent: Cheyenne Defense Research type XX6B low-heat caseless propellent
Available Bullet Types from Cheyenne Defense Research:
Standard Issue Flechette (Hi-velocity, light-weight, armor penetrating. Prone to tumbling, producing the “Cavity Effect” as observed in the 5.56 mm NATO. Suggested for use in carbine and PDW configurations). Muzzle velocity: 3670 FPS. Muzzle energy: 4136 J (both when tested with 18 inch carbine barrel)
Sabot-Discarding Match (Long-range, high accuracy. Match grade ammunition, guaranteed 2 MOA when used with Castle Arms 38 inch DMR barrel. Suggested for use in DMR configuration). Muzzle velocity: 3894 FPS. Muzzle energy: 4586 J ( both when tested with 38 inch DMR barrel)
Armor Piercing Explosive (cheap, heavy and powerful round. Has been documented to penetrate Stryker APC armor. Suggested for use in LMG configuration). Multiple velocity: 3260 FPS. Muzzle energy: 4512 J (both when tested with 30 inch LMG barrel)
Fire rate: 750 RPM
Action and Operation
Action: Gas-operated Rotating bolt.
Gas System: short stroke piston
Cocking System: Ambidextrous non-reciprocating side-mounted charging handle.
Safety: three stage safety system, magazine safety requires that the magazine be inserted before the weapon can fire, ambidextrous safety switch requires the weapon to be set to fire and trigger safety requires that button on the front of the trigger be fully depressed before the trigger can be pulled back (Like in the Austrian Glock pistol)
Fire Selection: The fire selection system is composed of two parts: the ambidextrous switch which can be set to either safe, semiautomatic or fully automatic, and the dual stage trigger: the trigger has two click points, in semiautomatic pulling the trigger back to the first click fires a single round, going all the way back has no effect, in fully automatic pulling the trigger to the first click fires a three shot burst and when it is pulled all the way back the weapon will continue to fire until it is released.
Field stripping and barrel changing system
In order to field strip the weapon, all an operator needs to do is to pull three pins: First the pin holding the gas block, front sight and flash suppressor in place, The user then simply pulls them off the front of the barrel as a single unit. Next, the pins holding the butt plate and upper receiver in-place are removed, The butt plate is slid down and the upper receiver is swung open. The user can then remove the bolt carrier and gas piston by simply pulling them out the back of the weapon, followed by the barrel in the same manner. At this point the barrel can be replaced with either a longer or shorter one, and the weapon reassembled. The fire control group and trigger can then be extracted from the weapon as a single unit and the gun is completely stripped and ready for cleaning. The entire process takes roughly 28.5 seconds to completely field strip and reassemble for cleaning, and 18.56 seconds to change barrels.
The weapon is compatible with any AR style RIS barrel shroud.
Carbine: 700 meters
PDW: 400 meters
DMR: 1000 meters
LMG: 850 meters
Base Unit: 350 US Dollars.
Base unit with VDCO SmartScope: 475 US Dollars
VanDan Combat Optics LLc. SmartScope M3c.
Lightweight, variable zoom holographic combat scope with built-in rangefinder developed by VDCO. Custom reticule. Option to select between X3 powers, X8 powers, and X12 powers. Drift lines and bullet drop guides will appear at the X8 and X12 settings. Automatic zeroing function allows the scope to be calibrated using the VDCO Laser Calibration System, simply insert the LCS dummy cartridge into the chamber, place the dot on a target at the distance to which you wish to calibrate to and hold the red button on the scope until you hear a beep and the reticule shifts. VDCO also offers a “starlight” attachment which can be attached to the weapon's RIS rail directly in front of the standard SmartScope.