Geissele Super Duty 5.56 NATO 10.3" 1:7" CHF Bbl Black Stripped Upper Receiver w/9.3" M-LOK MK16 SMR 08-244B

Geissele Super Duty 5.56 NATO 10.3" 1:7" CHF Bbl Black Stripped Upper Receiver w/9.3" M-LOK MK16 SMR 08-244B offers the craftsmanship and quality Geissele products are known for.

This Geissele Super Duty 10.3 upper comes equipped with Geissele's Super Modular MK16 Rail, attached via enhanced barrel nut, anti-rotation tabs, and set screws. That combination keeps the rail from pivoting even under extreme conditions — a real concern on a shorter build where every mounted accessory adds leverage a loose rail can't resist.

M-LOK mounting locations sit at 3, 6, and 9 o'clock, plus the upper and lower 45° positions for maximum accessory flexibility. A 12 o'clock Picatinny rail runs the top for optics and other Picatinny-based accessories. This Geissele 10.3 Super Duty barrel is manganese phosphate coated, cold hammer forged, and chrome-lined, precision machined at Geissele's North Wales, Pennsylvania facility.

Key Features:

• 10.3" cold hammer forged, chrome-lined barrel, 1:7 twist
• Manganese Phosphate coating
• 9.3" MK16 SMR, M-LOK at 3, 6, 9 o'clock plus upper/lower 45°
• 12 o'clock Picatinny top rail
• Enhanced barrel nut, anti-rotation tabs, set screws
• Stripped configuration — no BCG, charging handle, or muzzle device
• Black finish
• All NFA regulations apply at this barrel length

This Geissele Super Duty Upper 10.3 hands builders a properly manufactured barrel and rail, leaving the rest of the parts selection entirely up to them.