Complete mainspring assembly designed for the Ruger MK II or MK III. Mainspring components are wire EDM-cut and CNC-machined. Volquartsen mainspring does not feature the lock feature found on the Ruger factory MK III Mainspring. Mfg: Volquartsen
- Home
- Guns
- AR Rifles & PistolsCompleted AR rifles and pistols at great prices.
- AK Rifles & PistolsCompleted AK rifles and pistols at great prices.
- Traditional RiflesCompleted rifles at great prices.
- HandgunsCompleted handguns at great prices.
- ShotgunsComplete Shotguns
- BlemishedPrimary Tactical has a great selection of blemished rifles at discounted prices from the brands you know and trust.
- AR-10
- Complete UppersCompleted AR-10/.308 WIN/7.62x51mm uppers.
- Complete LowersAR-10/308 WIN/LR-308/6.5 Creedmoor Complete Lowers
- BarrelsAR-10/308 WIN/LR-308/6.5 Creedmoor Barrels
- Bolt CarriersAR-10/308 WIN/LR-308/6.5 Creedmoor Bolts and Bolt Carrier Groups
- BuffersAR-10/308 WIN/LR-308/6.5 Creedmoor Buffer Tubes and Kits
- Charging HandlesAR-10/308 WIN/LR-308/6.5 Creedmoor Charging Handles
- ForegripsAR-10/308 WIN/LR-308/6.5 Creedmoor Foregrips
- Gas BlocksAR-10/308 WIN/LR-308/6.5 Creedmoor Gas Blocks and Tubes
- Lower ReceiversAR-10/308 WIN/LR-308/6.5 Creedmoor Lower Receivers
- Lower PartsAR-10/308 WIN/LR-308/6.5 Creedmoor Lower Parts
- MagazinesAR-10/308 WIN/LR-308/6.5 Creedmoor Magazines
- Muzzle DevicesAR-10/308 WIN/LR-308/6.5 Creedmoor Muzzle Devices. Flash hiders, compensators and muzzle brakes.
- Parts KitsAR-10/308 WIN/LR-308/6.5 Creedmoor Upper and Lower Parts Kits
- Pistol GripsAR-10/308 WIN/LR-308/6.5 Creedmoor Pistol Grips
- Rails & HandguardsAR-10/308 WIN/LR-308/6.5 Creedmoor Rails and Handguards
- Rifle KitsAR-10/308 WIN/LR-308/6.5 Creedmoor Rifle Build Kits
- StocksAR-10/308 WIN/LR-308/6.5 Creedmoor Stocks
- Upper PartsAR-10/308 WIN/LR-308/6.5 Creedmoor Upper Parts
- Upper ReceiversAR-10/308 WIN/LR-308/6.5 Creedmoor Upper Receivers
- AR-15
- Complete UppersComplete AR-15/.223/300 BLK/450 Bushmaster uppers.
- Complete LowersAR-15/.223/300 BLK/450 Bushmaster Complete Lowers
- BarrelsAR-15/.223/300 BLK/450 Bushmaster Barrels
- Bolt CarriersAR-15/.223/300 BLK/450 Bushmaster Bolts and Bolt Carrier Groups
- BuffersAR-15/.223/300 BLK/450 Bushmaster Buffer Tubes
- Charging HandlesAR-15/.223/300 BLK/450 Bushmaster Charging Handles
- ForegripsAR-15/.223/300 BLK/450 Bushmaster Foregrips
- Gas BlocksAR-15/.223/300 BLK/450 Bushmaster Gas Blocks
- Lower ReceiversAR-15/.223/300 BLK/450 Bushmaster Lower Receivers
- Lower PartsAR-15/.223/300 BLK/450 Bushmaster Lower Parts
- MagazinesAR-15/.223/300 BLK/450 Bushmaster Magazines
- Muzzle DevicesAR-15/.223/300 BLK/450 Bushmaster Muzzle Devices. Flash hiders, compensators and muzzle brakes.
- Parts KitsAR-15/.223/300 BLK/450 Bushmaster Parts Kits
- Pistol GripsAR-15/.223/300 BLK/450 Bushmaster Pistol Grips
- Rails & HandguardsAR-15/.223/300 BLK/450 Bushmaster Rails and Handguards
- Rifle KitsAR-15/.223/300 BLK/450 Bushmaster Rifle Build Kits
- StocksAR-15/.223/300 BLK/450 Bushmaster Stocks
- Upper PartsAR-15/.223/300 BLK/450 Bushmaster Upper Parts
- Upper ReceiversAR-15/.223/300 BLK/450 Bushmaster Upper Receivers
- Rifle Parts
- Barrel Parts
- Bolt Parts
- Forend & Handguard Parts
- Gas System Parts
- Grip Parts
- Rifle MagazinesPrimary Tactical has a great selection of rifle magazines. Check here to find the right caliber from the brands you know and trust.
- Muzzle Devices
- Receiver Parts
- Safety Parts
- Sights
- Stock Parts
- Trigger Parts
- Handgun Parts
- Action PartsGreat selection of handgun action parts from trusted brands.
- Barrel PartsGreat selection of handgun barrel parts from trusted brands.
- Frame Parts
- Grip Parts
- Handgun MagazinesLarge selection of handgun magazines from the brands you trust.
- Receiver Parts
- Recoil Parts
- Safety Parts
- Sights
- Slide Parts
- Trigger Group Parts
- Shotgun Parts
- Optics
- Electronic SightsThe best selection of electronic sights you’ll find from the brands you trust.
- Scopes
- Mounts & BasesThe best selection of mounts and bases for your optics that you’ll find from the brands you trust.
- Action Cameras
- Binoculars & Accessories
- Optic Accessories
- Rangefinders
- Rings
- Spotting Scopes & Accessories
- Night VisionPrimary Tactical has the best selection of night vision optics from the brands you trust.
- Accessories
- BipodsPrimary Tactical offers a great selection of firearm bipods for your rifles.
- HolstersPrimary Tactical offers a great selection of firearm holsters for your handguns.
- Magazine CarriersPrimary Tactical offers a great selection of magazine carriers.
- SlingsPrimary Tactical offers a great selection of firearm slings for your rifles.
- Ammunition
- Rifle Ammo
- Handgun Ammo
- Shotgun Ammo
- Rimfire Ammo
- Ammo BoxesPrimary Tactical has a variety of ammo boxes for your ammunition storage needs.
- Reloading
- Gun Cleaning
- Gunsmithing
- Books & Videos
- Safety Equipment
- Shop Accessories & Supplies
- General Gunsmith ToolsPrimary Tactical has all the gunsmithing tools and supplies you need.
- Barrel ToolsPrimary Tactical has a variety of Barrel Tools for your gunsmithing needs.
- Handgun ToolsPrimary Tactical has a variety of Handgun Tools for your gunsmithing needs.
- Rifle ToolsPrimary Tactical has a variety of Rifle Tools for your gunsmithing needs.
- Measuring Tools
- Metal Prep & Coloring
- Power Tools & Accessories
- Shotgun Tools
- Sight & Scope Installation Tools
- Small Hardware
- Stock Work & Finishing
- Armor
- Home
- Guns
- AR Rifles & PistolsCompleted AR rifles and pistols at great prices.
- AK Rifles & PistolsCompleted AK rifles and pistols at great prices.
- Traditional RiflesCompleted rifles at great prices.
- HandgunsCompleted handguns at great prices.
- ShotgunsComplete Shotguns
- BlemishedPrimary Tactical has a great selection of blemished rifles at discounted prices from the brands you know and trust.
- AR-10
- Complete UppersCompleted AR-10/.308 WIN/7.62x51mm uppers.
- Complete LowersAR-10/308 WIN/LR-308/6.5 Creedmoor Complete Lowers
- BarrelsAR-10/308 WIN/LR-308/6.5 Creedmoor Barrels
- Bolt CarriersAR-10/308 WIN/LR-308/6.5 Creedmoor Bolts and Bolt Carrier Groups
- BuffersAR-10/308 WIN/LR-308/6.5 Creedmoor Buffer Tubes and Kits
- Charging HandlesAR-10/308 WIN/LR-308/6.5 Creedmoor Charging Handles
- ForegripsAR-10/308 WIN/LR-308/6.5 Creedmoor Foregrips
- Gas BlocksAR-10/308 WIN/LR-308/6.5 Creedmoor Gas Blocks and Tubes
- Lower ReceiversAR-10/308 WIN/LR-308/6.5 Creedmoor Lower Receivers
- Lower PartsAR-10/308 WIN/LR-308/6.5 Creedmoor Lower Parts
- MagazinesAR-10/308 WIN/LR-308/6.5 Creedmoor Magazines
- Muzzle DevicesAR-10/308 WIN/LR-308/6.5 Creedmoor Muzzle Devices. Flash hiders, compensators and muzzle brakes.
- Parts KitsAR-10/308 WIN/LR-308/6.5 Creedmoor Upper and Lower Parts Kits
- Pistol GripsAR-10/308 WIN/LR-308/6.5 Creedmoor Pistol Grips
- Rails & HandguardsAR-10/308 WIN/LR-308/6.5 Creedmoor Rails and Handguards
- Rifle KitsAR-10/308 WIN/LR-308/6.5 Creedmoor Rifle Build Kits
- StocksAR-10/308 WIN/LR-308/6.5 Creedmoor Stocks
- Upper PartsAR-10/308 WIN/LR-308/6.5 Creedmoor Upper Parts
- Upper ReceiversAR-10/308 WIN/LR-308/6.5 Creedmoor Upper Receivers
- AR-15
- Complete UppersComplete AR-15/.223/300 BLK/450 Bushmaster uppers.
- Complete LowersAR-15/.223/300 BLK/450 Bushmaster Complete Lowers
- BarrelsAR-15/.223/300 BLK/450 Bushmaster Barrels
- Bolt CarriersAR-15/.223/300 BLK/450 Bushmaster Bolts and Bolt Carrier Groups
- BuffersAR-15/.223/300 BLK/450 Bushmaster Buffer Tubes
- Charging HandlesAR-15/.223/300 BLK/450 Bushmaster Charging Handles
- ForegripsAR-15/.223/300 BLK/450 Bushmaster Foregrips
- Gas BlocksAR-15/.223/300 BLK/450 Bushmaster Gas Blocks
- Lower ReceiversAR-15/.223/300 BLK/450 Bushmaster Lower Receivers
- Lower PartsAR-15/.223/300 BLK/450 Bushmaster Lower Parts
- MagazinesAR-15/.223/300 BLK/450 Bushmaster Magazines
- Muzzle DevicesAR-15/.223/300 BLK/450 Bushmaster Muzzle Devices. Flash hiders, compensators and muzzle brakes.
- Parts KitsAR-15/.223/300 BLK/450 Bushmaster Parts Kits
- Pistol GripsAR-15/.223/300 BLK/450 Bushmaster Pistol Grips
- Rails & HandguardsAR-15/.223/300 BLK/450 Bushmaster Rails and Handguards
- Rifle KitsAR-15/.223/300 BLK/450 Bushmaster Rifle Build Kits
- StocksAR-15/.223/300 BLK/450 Bushmaster Stocks
- Upper PartsAR-15/.223/300 BLK/450 Bushmaster Upper Parts
- Upper ReceiversAR-15/.223/300 BLK/450 Bushmaster Upper Receivers
- Rifle Parts
- Barrel Parts
- Bolt Parts
- Forend & Handguard Parts
- Gas System Parts
- Grip Parts
- Rifle MagazinesPrimary Tactical has a great selection of rifle magazines. Check here to find the right caliber from the brands you know and trust.
- Muzzle Devices
- Receiver Parts
- Safety Parts
- Sights
- Stock Parts
- Trigger Parts
- Handgun Parts
- Action PartsGreat selection of handgun action parts from trusted brands.
- Barrel PartsGreat selection of handgun barrel parts from trusted brands.
- Frame Parts
- Grip Parts
- Handgun MagazinesLarge selection of handgun magazines from the brands you trust.
- Receiver Parts
- Recoil Parts
- Safety Parts
- Sights
- Slide Parts
- Trigger Group Parts
- Shotgun Parts
- Optics
- Electronic SightsThe best selection of electronic sights you’ll find from the brands you trust.
- Scopes
- Mounts & BasesThe best selection of mounts and bases for your optics that you’ll find from the brands you trust.
- Action Cameras
- Binoculars & Accessories
- Optic Accessories
- Rangefinders
- Rings
- Spotting Scopes & Accessories
- Night VisionPrimary Tactical has the best selection of night vision optics from the brands you trust.
- Accessories
- BipodsPrimary Tactical offers a great selection of firearm bipods for your rifles.
- HolstersPrimary Tactical offers a great selection of firearm holsters for your handguns.
- Magazine CarriersPrimary Tactical offers a great selection of magazine carriers.
- SlingsPrimary Tactical offers a great selection of firearm slings for your rifles.
- Ammunition
- Rifle Ammo
- Handgun Ammo
- Shotgun Ammo
- Rimfire Ammo
- Ammo BoxesPrimary Tactical has a variety of ammo boxes for your ammunition storage needs.
- Reloading
- Gun Cleaning
- Gunsmithing
- Books & Videos
- Safety Equipment
- Shop Accessories & Supplies
- General Gunsmith ToolsPrimary Tactical has all the gunsmithing tools and supplies you need.
- Barrel ToolsPrimary Tactical has a variety of Barrel Tools for your gunsmithing needs.
- Handgun ToolsPrimary Tactical has a variety of Handgun Tools for your gunsmithing needs.
- Rifle ToolsPrimary Tactical has a variety of Rifle Tools for your gunsmithing needs.
- Measuring Tools
- Metal Prep & Coloring
- Power Tools & Accessories
- Shotgun Tools
- Sight & Scope Installation Tools
- Small Hardware
- Stock Work & Finishing
- Armor
