Spikes Tactical ST-15 Jolly Roger 5.56 NATO Semi-Auto Rifle – SIG MCX SPEAR LT 16 in Piston Upper, Folding 1913 Stock, Geissele Controls
This custom AR-15 platform pairs a Spikes Tactical ST-15 Jolly Roger lower with a SIG MCX SPEAR LT 16-inch 5.56 upper for a piston-driven, buffer-tube-free build with a 1913 folding stock interface. It features Geissele Maritime bolt catch and Geissele magazine release controls, an ambidextrous charging handle with extended latches, and a three-prong flash hider on a 1/2x28 threaded muzzle. The two-tone FDE upper and black lower, Jolly Roger roll mark, and unique selector legend add distinctive character to a capable, feature-rich configuration.
Condition
Overall Condition: Very good condition, showing only light, superficial signs of prior handling or use.
Bore Condition: Excellent - Clean, mirror finish, no signs of wear.
Bore Rifling: Excellent Rifling - Sharp lands and grooves.
Specific Condition Notes: There are some minor scratches and blemishes present. The bore is clean and shiny.
What’s Included
- 2x 30-round Magpul PMAG polymer AR-15 pattern magazines
- Geissele Automatics Maritime Bolt Catch installation instructions
- Geissele Maritime bolt catch (installed)
- Geissele magazine release (installed)
- Magpul pistol grip (installed)
- BCM M-LOK vertical foregrip (installed)
- M-LOK Picatinny accessory rail section (installed)
- 1913-pattern side-folding skeleton stock (installed)
- Ambidextrous charging handle with extended latches (installed)
- Three-prong flash hider (installed)
This hybrid build centers on the SIG MCX SPEAR LT upper, bringing a short-stroke gas piston system with an adjustable gas block and an internal recoil assembly. Because it does not require a buffer tube, the rifle uses a 1913 Picatinny rear stock interface and a folding, skeletonized stock for compact storage and transport.
The upper provides a continuous 12 o'clock Picatinny rail with no forward assist and a free-float MCX LT aluminum handguard featuring M-LOK at 3, 6, and 9 o'clock, rear link plates, and trunnion clamp screws. The 16-inch barrel is threaded 1/2x28 and capped with a three-prong flash hider.
The lower is the Spikes Tactical ST-15 Jolly Roger variant, distinguished by its pirate roll mark and the themed selector legend marked "PARLEY / PLUNDER / ARRR." Controls are upgraded with a Geissele Maritime bolt catch and a Geissele magazine release for confident manipulation.
User-focused features include an ambidextrous charging handle with extended latches, a Magpul polymer pistol grip, and a BCM M-LOK vertical foregrip. The rifle carries a two-tone finish with an FDE upper and black lower, and offers a 12-inch length of pull.
Chambered in 5.56mm NATO with a 30+1 capacity, this AR-15 platform build combines the MCX piston system with the distinctive Spikes Jolly Roger lower and quality components throughout, assembled in the USA.