// Parts
Upper and lower parts.
The components we fit to our own firearms — measured, marked and checked by us.
// Upper parts
Upper parts
Barrels
A wide range of calibers in lengths from 8″ to 24″, including the HM Defense Monobloc®.
Fitting an LMT® MRP™ upper? See LMT® MRP™ Compatible Barrels.
Bolt Carrier Groups
Complete groups, including SOT Enhanced groups with the HM Defense HMB™ bolt.
- C158 MPI bolts
- Hard chrome · DLC · nitride
- Index-marked gas key
- Small & large frame
Bolt Carrier Group Parts
HMB™ bolts, the SOT Enhanced Chrome Bolt, SOT arrow-indexed cam pins with the SOT arrowhead laser-marked on the flag, firing pins and carrier completion kits.
LMT® MRP™ Compatible Barrels
HM Defense Monobloc® barrels converted by Second of Ten to fit the LMT® MRP™ upper receiver, paired with the HMB™ bolt.
Not an MRP™ build? See the full barrel range.
Muzzle Devices
The muzzle devices fitted to our own firearms, plus suppressor mounts from many manufacturers.
- Brakes & comps
- Flash hiders
- Suppressor mounts
- Plan B mounts
- As fitted to our rifles
Gas System Components
RIFLESPEED adjustable Gas Controls and plungers, and low-profile gas blocks, pinned to the barrel the way we pin our own.
- RIFLESPEED
- Plungers
- Low-profile gas blocks
- Pinned
// Lower parts
Lower parts
Triggers
The LaRue MBT-2S is our standard fit and the best value in the range; Geissele G2S®, SSA® and SSA-E® sit above it.
- LaRue MBT-2S standard
- Two-stage & single-stage
- Curved & straight bow
- Geissele upgrades
Furniture
Stocks and grips, including the Reptilia RECC·E™ Carbine stock — constant cheek weld through its full length-of-pull range.
Buffer System Parts
There are only three ways to handle the energy: add mass, add distance, or subtract it. Extension tubes, springs and weights, castle nuts, hydraulic buffers and folding adapters.
- SOTA5 indexed extension
- VLTOR A5
- FCD CN5F
- KynSHOT
- Law Tactical folder
Looking for a complete lower receiver? It is a firearm and ships to your FFL, so it has its own section: Lower Receiver Groups →
// SOT Custom Shop
Fitted work, not just parts in a box.
Conversions, gas-system tuning and enhanced builds on other manufacturers’ platforms — the work we do to our own firearms, done to yours.
// Can’t find it here?
Gundaddy.com carries the rest.
Our retail store stocks the manufacturers this page does not.
Monobloc® and HMB™ are marks of HM Defense, LLC, used under license. LMT® is a registered trademark and MRP™ (Monolithic Rail Platform) is a trademark of Lewis Machine & Tool Company. Other product names are marks of their respective owners.
Bombproof by Design™
Precision // Purpose // Performance