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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 7160 Tipped MatchKing 22 Caliber 60 Grain 100 Count Bullets
Sierra 5400 Sports Master .50 Cal 400gr JSP Handgun Bullets 50ct
Sierra 5350 Sports Master .50 Cal 350gr JHP Handgun Bullets 50ct
Sierra 4681 Tipped GameKing 30Cal 180gr 100/Box
Sierra 4680 Tipped GameKing 308 Win 180 Grain Boat Tail 100 Count
Sierra 4665 Tipped GameKing 308Win 165gr 100/Box Hunting Bullets
Sierra 4625 Tipped GameKing .30 Caliber 125 Grain 100 Count Bullets
Sierra 4580 Green Tipped GameKing 7mm .284 180gr Hunting Bullets 100ct
Sierra 4565 Tipped GameKing 7mm 165gr HPBT Bullets 100/Box
Sierra 4550 Tipped GameKing 7mm .284 150 gr - 100 Per Box
Sierra Bullets Tipped GameKing 7mm .284 Caliber 140 Gr 100 Rounds
Sierra Bullets 270 Win 175gr Tipped GameKing Reloading Bullets 100/Box
Sierra 4440 Tipped GameKing 270Win 140gr HPBT 100/Box
Sierra 4345 Green Tipped GameKing 6.5mm .264 145gr Rifle Bullets 100ct
Sierra 4340 Tipped GameKing Bullets 6.5mm .264 140gr 100/rd
Sierra 4330 Tipped GameKing 6.5 Creedmoor 130gr HPBT 100/Box
Sierra 4320 Green Tipped GameKing 6.5mm .264 120gr TGK Bullets 100ct
Sierra Tipped GameKing Rifle Bullets 6mm .243 cal .243" 100 gr BT 100-ct
Sierra 4100 Tipped GameKing 6mm .243 90 Grain HPBT 100 Count
Sierra 4062 Tipped GameKing .22 Cal .224 64 gr 100 Per Box: Optimal thickness, instant expansion, industry-leading BC.
Sierra Bullets 3000 375 Cal 300gr Spitzer Boat Tail 50/Box
Sierra 2950 GameKing 375 Cal .375 250 GR SBT 50 Per Box
Sierra Pro-Hunter Rifle Bullets .375 cal .375" 200 gr FN 50-ct
SIERRA GameKing .35 Caliber (.358) 225Gr SBT 50 Box Bullets (2850)
Sierra 2800 Pro-Hunter 35 Cal .358 200 GR RN 50 Per Box
Sierra 2755 Pro-Hunter 35Cal 115gr Flat Nose Bullets 100/Box
Sierra 2650 MatchKing .338 250gr HPBT Bullets 50/Box
Sierra 2620 338 Caliber 225gr Spitzer Pointed Bullets 50/Box
Sierra 2610 GameKing .338 Cal 215GR Spitzer Boat Tail 50/Box
Sierra 2600 GameKing 338 Cal .338 250 GR SBT 50 Per Box
Sierra 2420 8mm 220gr Spitzer Boat Tail Bullets 50/Box
Sierra Bullets 2415 8mm 200gr HPBT Rifle Bullets 100/Box
SIERRA Pro-Hunter 8mm (.323) 175Gr Spitzer 100 Box Bullets (2410)
Sierra 2400 Pro-Hunter 8mm 150gr Spitzer Bullets 100/Box
Sierra 2315 MatchKing .311 174gr HPBT Rifle Bullets 100/Box
Sierra Pro-Hunter Rifle Bullets .303 cal-7mm .311" 180 gr SPT 100-ct
Sierra 2305 Pro-Hunter 303 Cal 125gr Spitzer Bullets 100/Box
Sierra 2300 Pro-Hunter .311 Cal 150gr Spitzer Bullets 100ct Box
Sierra 2275 MatchKing .308 175gr HPBT Match Grade
Sierra Bullets HPBT-CN Matchking 30 Cal .308 169 Gr 100/rd Boattail
Sierra MatchKing .30 cal / 7.62mm .308 230gr HPBT MatchKing Bullets 50/ct - Accurate, Long Range Performance
Sierra 2240 .308 220gr HPBT Match Grade Reloading Bullets
Sierra GameKing Rifle Bullets .30 cal .308 205 gr HPBT/CN 100/ct
Sierra 2232 MatchKing-X 30Cal 200gr HPBT 100/Box
Sierra Bullets 2231 30 Cal 200gr MatchKing HPBT 100-Box
Sierra 2230 MatchKing .308 200gr HPBT Bullets 100/Box
Sierra 2210 MatchKing 30Cal 190gr HPBT Bullets 100/Box
Sierra 2200 MatchKing 30 Cal .308 168 gr HPBT 100 Per 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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