JAG™ 18″ BUILDER KIT 5.56mm – Olive | Earth | Charcoal

Our builder kits consist of a complete upper with a JR BCG, mil-spec charging handle, and complete lower. Both components are ready to be assembled by the end user.

Note: You must be 21+ to purchase a serialized lower. Lower receivers will be shipped to your provided FFL while upper receivers will be shipped to you. Please allow for 2-4 week lead time for parts assembly and QC. 

Barrel: L&S’s 4150CMV, stress relieved, 1/8 twist 18″ rifle length barrel is gas nitrocarburized for longevity, and is capable of match grade accuracy with Black Hills® MK262 ammunition. Barrels are batch HP/MPI and accuracy tested at 100yds. Gas port is drilled to 0.093″ for a smoother shooting rifle that retains reliable extraction and ejection in a variety of environmental conditions.

(Please note that the L&S JAG barrel is a Maryland-compliant HBAR with an aesthetic akin to a traditional government profile barrel. It’s still an HBAR though, because it’s ours and we said so.)

Bolt Carrier Group: The JAG SPR utilizes the L&S M16 JRBCG, a properly heat treated 9310 bolt with a corrected internal carrier gas ring run to compensate for black nitride’s three micron coating depth, extending gas ring service life and proving a “Just Right” seal.

Handguard: Free floated and secured via wedge locking system, the JAG rail is a durable handguard that retains a continuous 12 o’clock 1913 section and multiple MLOK attachment points for whatever goober-tier accessories you have in mind.

Receiver Set: Borrowed from the ARC, L&S’s 7075 forged receiver set comes with an M16 FCG pocket and Type III hard coat anodizing for added coating longevity.

Gas Drive: L&S utilizes the 4140CMV machined quality gas block (QGB) for paralleled thermal expansion, which is secured to the dimpled barrel via degreased, thread locked, serrated gas block screws torqued to 25 in/lbs.

Trigger: Our LPK includes the Enhanced Reliability Combat Trigger (ERCT) borrowed from the ARC to give the JAG a sub 4lb trigger, with full mass hammer and mil std. springs for reliable primer ignition.

Controls: The JAG SPR comes preinstalled with an enlarged trigger guard, bolt catch, and ergonomic Thril® and Magpul® furniture.

Why spend lot money when few money do trick?

Lead & Steel lifetime warranty.