Jp Enterprises JP15 Stripped AR-15 Forged Lower Receiver. For anyone starting an AR build from the ground up, you can’t go wrong with choosing high-quality components. JP’s stripped receivers are the very same ones used in their own rifle builds, manufactured, machined and finished to their exacting standards. The forged JP-15™ model accepts all standard Mil-spec components but rise above most any others on the market. JP’s Mil-spec JP-15™ receivers must face high reject rate attrition before we’ll put our name on them. The JP-15™ lower receiver is manufactured using the highest quality 7075 T6 forging and precision machined to mate up to any Mil-spec upper receiver and components. Finished in the Mil-spec hard coat process and coated with Black Teflon™ for perfect cosmetic appearance and natural lubricity.