Founded in 2008 by passionate firearm enthusiasts, Primary Weapons Systems began its journey by developing innovative muzzle devices. Through extensive testing on various rifles, including M4s and AK-47s, they discovered a significant difference in maintenance requirements after high-round-count use. This realization led to the creation of the PWS long-stroke piston system, which preserves the core functionality of the AR-15 while reducing maintenance needs in high-volume shooting and harsh conditions. The Compound Rifle exemplifies this commitment to performance, combining a Mod 1 upper with the MK1 Mod 2 lower to deliver exceptional reliability, durability and versatility for demanding shooters. Operating system PWS long stroke piston system with a 3-setting adjustable gas regulator for maximum versatility A mid-length gas system provides smoother recoil impulse and improved reliability for a balanced shooting experience The upper receiver is a PWS proprietary piston upper, made from 7075-T6 forged aluminum and anodized for durability The PWS M-LOK 15.05 Inches handguard (1.7 Inches width, 2.25 Inches height) offers a slim, ergonomic profile with robust accessory mounting options Equipped with a Radian Raptor ambidextrous charging handle for superior control and ease of operation The PWS ambidextrous MK1 MOD 2-M lower receiver is crafted from 7075-T6 forged aluminum, offering durability and full AR-15 compatibility This model features a Mil-Spec enhanced trigger with a PTFE-coated surface for smooth performance Includes a PWS enhanced buffer tube with a ratchet lock castle nut, end plate set and built-in QD mount for added stability and attachment options PWS enhanced H2 steel body buffer reduces recoil and enhances reliability for smoother cycling Outfitted with Bravo Company USA furniture, including a durable buttstock and ergonomic pistol grip for enhanced handling