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SI designs rugged, user-focused firearm components and optics. They make accessories like slide plates, charging handles, barrel clamps, red dots, and shotgun parts.
All SI Products (2,389)
Sierra 2190 MatchKing 30 Cal .308 150 gr HPBT - 100 Per Box
Sierra 2180 Pro-Hunter 30Cal 220gr Round Nose Bullets 100/Box
Sierra 2175 MatchKing-X 30Cal 175gr HPBT 100/Box
Sierra Pro-Hunter 2170 .30 Cal .308 180gr RN Rifle Bullets 100ct
Sierra 2165 GameKing 30 Cal 200gr Spitzer Boat Tail Bullets 100/Box
Sierra 2160 GameKing 30 Cal 180gr Spitzer Boat Tail Bullets 100/Box
Sierra .30 Cal 155 Grain HPBT MatchKing Bullets
Sierra 2155 MatchKing 30 Cal .308 155 gr HPBT 100 Per Box
Sierra 2145 GameKing 30 Cal .308 165gr SBT 100 Per Box
Sierra 2140 GameKing 30 Cal .308 165gr HPBT 100 Per Box
Sierra 2136 Varminter 30 Caliber 150 Grain Hollow Point 100 Count
Sierra 2135 Pro-Hunter 30 Cal 150gr Round Nose Bullets 100/Box
Sierra 2130 Pro-Hunter 30 Cal .308 150 gr Spitzer 100 Per Box
Sierra 2125 GameKing 30 Cal .308 150 gr Spitzer Boat-Tail (SBT) 100 Per Box
Varminter Bullets 30 Cal 135Gr HP - 100 Box Pack
Sierra .30 Caliber 125 Grain HP MatchKing Rifle Bullets
Sierra 2120 Pro-Hunter 30 Cal .308 125 gr Spitzer 100 Per Box
Sierra Bullets 2116 30 Cal 115gr Hollow Point Varminter 100/Box
Sierra 2115 GameKing .30 Cal 150gr FMJ Boat Tail Bullets 100/Box
Sierra 2110 Varminter 30 Cal .308 110gr HP 100 Per Box
Sierra 2100 Pro-Hunter 30 Cal .308 110 gr RN 100 Per Box
Sierra 2020 Pro-Hunter 30 Cal 125gr HP Flat Nose Bullets 100/Box
Sierra 2010 Pro-Hunter 30 Cal .308 170 gr Flat Nose (FN) 100 Per Box
Sierra 2000 Pro-Hunter .30 Cal 150 Grain FN Rifle Bullets
Sierra 1997 MatchKing 7mm 197gr HPBT Bullets 100/Box
Sierra 1983 MatchKing 7mm .284 183gr HPBT Rifle Bullets 100ct
Sierra MatchKing Rifle Bullets 7mm .284 180 gr HPBT/CN 100/ct
Matchking 7MM (0.284") Hollow Point Boat Tail Bullets 1980
Sierra 1976 MatchKing-X 7mm 175gr Hollow Point Boat Tail 100/Box
Sierra 1975 MatchKing 20Cal 175gr HPBT Bullets 100/Box
Sierra 1940 GameKing 7mm 175gr Spitzer Boat Tail 100/Box
Sierra 1930 MatchKing 7mm 168gr HPBT Bullets 100/Box
SIERRA GameKing 7mm (.284) 160Gr HPBT 100 Box Bullets (1925)
Sierra 1920 GameKing 7mm 160gr Spitzer Boat Tail 100/Box
Sierra 1915 MatchKing 7mm/.284 150gr HPBT Rifle Bullets 100ct
Sierra 1913 GameKing 7mm 150gr Spitzer Boat Tail 100/Box
Sierra 1912 GameKing 7mm 140gr HPBT Bullets 100/Box
Sierra 1910 Pro-Hunter 7mm .284 140 gr Spitzer 100 Per Box
SIERRA GameKing 7mm .284 Cal 140Gr Spitzer Boat Tail 100 Rifle Bullets 1905
Sierra 1900 Pro-Hunter 7mm .284 120gr Spitzer 100 Per Box
Sierra 1895 Varminter 7mm 100gr Hollow Point Bullets 100/Box
Sierra 1845 GameKing 270Win 140gr Spitzer Boat Tail 100/Box
Sierra 1840 GameKing 270Win 150gr Spitzer Boat Tail 100/Box
Sierra 1835 GameKing 270Win 140gr HPBT 100/Box
Sierra 1834 MatchKing-X 270Cal 135gr HPBT 100/Box
Sierra 1830 Pro-Hunter 270 Win .277 130 gr Spitzer 100 Per Box
Sierra 1820 GameKing 270 Win 130 Grain Spitzer Boat Tail 100 Rounds
Sierra 1815 MatchKing 270Win 115gr HPBT Bullets 100/Box
About SI
Headquarters
Established
-
Country of Origin
USA
History & Heritage
SI began as an American aftermarket parts maker aimed at providing functional, affordable upgrades and accessories for shooters. Over time the brand expanded its offerings across pistol, rifle, and shotgun platforms, becoming known for practical designs and broad compatibility.
Notable Products
Popular items include charging handles, slide adapter plates, red dot sights, barrel clamps, and shotgun conversion components.
Why Choose SI?
Choose SI for straightforward, well-engineered accessories that improve usability and durability without unnecessary complexity.
Hot SI Items June 2026
Trending right now based on the last 30 days of TheGunDock orders + page views.
SilencerCo Sparrow 22 Rimfire Suppressor 22LR 5.08" Stainles
SIG SAUER 322C-ROSE-RS P322 Rose 22 LR 4" Black Anodize Semi
Sig Sauer Tango-MRS Compact Rifle Scope 1-6x24 30mm SFP BDC6
Sig Sauer Cross Sawtooth Rifle 6.5 PRC 22 inch Moss Green Fo
Sig Sauer W365XL-9-BXR3P-MS P365 XL 9mm 3.7" Nitron Semi-Aut
Sig Sauer 2401191R Picatinny Stock Adapter for AR-15, Alumin
Sig Sauer SORX1080 24MM Black Pro Optics Ready Sight
SIG SAUER E26R-9-BSS-FBZ P226 Full-Size 9mm 4.4" 2-Tone Bron
Shop SI Products
Sig SAUER MCX-SPEAR 6.8x51mm SBR 13in Semi-Auto Rifle RSPEAR
SilencerCo Sparrow 22 Rimfire Suppressor 22LR 5.08" Stainles
Sig Sauer P320 FLUX 9MM 3.9" 30RD Legion 320
Sig Sauer SLH300TIQD 300 Blackout Titanium Suppressor
SilencerCo Velos LBP 5.56 NATO/.223 4.76 In Low Back-Pressur
SIG SAUER MCX Spear SBR 7.62x51mm 13" Nitride NFA
Sig Sauer P365X Macro Tacops 9mm 3.7" 17rd Pistol
Sinclair INTERNATIONAL DIAL INDICATOR .001
Sig Sauer ROMEO1 Black Shroud Kit SOR1SK001: Medium Size, Ne
Sig Sauer 8900823 LTXG Grip Module Laser Engraved P320-X Car
Sig Sauer MCX-SPEAR LT AR Conversion Kit 5.56 NATO 11.5" Bla
Sig SAUER MCX 5.56 NATO 16in 30rd IR Cerakote FDE Rifle RMCX
SI News & Articles
Firearm Shipping Restrictions by State (2026 Update)
State-by-state guide to firearm and ammunition shipping for online buyers and FFL dealers. Current as of May 2026. Cover...
Damaged in Transit: How TheGunDock Handles Shipping Claims on Firearms and Ammo
When a firearm or ammo shipment arrives damaged, the claim process matters. TheGunDock walks through what to do, what we...
The Springfield KUNA: Roller-Delayed 9mm Pistol That's Shaking Up the PDW Market
The Springfield Armory KUNA — a roller-delayed 9mm pistol built in partnership with Croatia's HS Produkt — has becom...
The Strait of Hormuz: 2,500 Years of Trade, Arms, and Conflict
A twenty-one-mile-wide choke point has shaped the movement of goods — and weapons — across half the ancient and mode...
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