EGW Keystone 1-Inch Medium Scope Rings
EGW Keystone .990-inch medium-profile scope rings provide additional clearance for scopes with a 1-inch main tube while maintaining a practical mounting height. These rings are precision CNC-machined from 6061 aluminum at our Quakertown, Pennsylvania facility and designed for Picatinny and Weaver-style cross-slot rails.
Keystone is the flagship of the EGW scope ring lineup, combining a streamlined horizontal-split design, Chromoly crossbolts, secure cap hardware, and 100% American manufacturing.
This Configuration
- Scope tube: 1 inch
- Centerline height: .990 inch
- Profile: Medium
- Rail type: Picatinny or Weaver-style
- Quantity: One pair of rings
A Versatile Medium Height
The .990-inch measurement is taken from the top of the mounting rail to the centerline of the scope tube. This medium height provides more clearance than the .850-inch low rings and is commonly chosen for 1-inch scopes with 50mm objectives, scope caps, heavier barrel contours, and other setups requiring additional room.
Why Choose Keystone 1-Inch Scope Rings?
Precision CNC-Machined
Machined from 6061 aluminum to maintain consistent dimensions and mating surfaces while keeping unnecessary weight out of the mounting system.
Horizontal-Split Design
The horizontal split provides straightforward scope positioning and allows the ring-cap screws to be tightened evenly during installation.
Chromoly Crossbolts
Chromoly crossbolts provide a strong mechanical connection between the rings and a compatible cross-slot mounting rail.
Cross-Slot Compatibility
Keystone rings are designed to mount to Picatinny and Weaver-style cross-slot rails, giving shooters flexibility across a wide range of rifle setups.
Versatile .990-Inch Height
The medium centerline provides additional room for larger objective bells, scope caps, heavier barrels, and rifle configurations that need more clearance.
Made in Pennsylvania
Keystone rings are 100% American-made and manufactured by EGW at our facility in Quakertown, Pennsylvania.
Product Specifications
| Series | Keystone |
|---|---|
| SKU | 62001 |
| Scope Tube Diameter | 1 inch |
| Ring Height | .990 inch, measured from the top of the rail to the scope centerline |
| Profile | Medium |
| Material | 6061 aluminum |
| Finish | Matte black anodized |
| Rail Compatibility | Picatinny and Weaver-style cross-slot rails |
| Construction | Horizontal split with Chromoly crossbolts |
| Crossbolt Torque | 65 inch-pounds |
| Ring-Cap Torque | 15 inch-pounds maximum, subject to the scope manufacturer's limit |
| Quantity | Sold as one pair |
| Manufactured In | Quakertown, Pennsylvania, USA |
| GTIN | 841370117888 |
Will .990-Inch Medium Rings Fit Your Scope?
The .990-inch medium height is a common starting point for 1-inch scopes with 50mm objectives and other setups that require more clearance than the .850-inch low rings provide. Objective size alone cannot guarantee fitment.
Measure and account for:
- The objective bell's actual outside diameter
- Rail height above the receiver
- Barrel diameter and contour
- Scope-cap or lens-cover thickness
- Bolt-handle and action clearance
- Power-selector and magnification-ring clearance
- Stock or chassis comb height
Minor fitment may be required. Always verify that the scope, objective bell, caps, controls, and bolt handle move freely without contacting the rifle.
Use the EGW Ring Height CalculatorCompare 1-Inch Keystone Ring Heights
.990-Inch Medium
A versatile balance of mounting height and clearance
Installation and Torque
Confirm the firearm is unloaded before beginning installation. Inspect and clean the rail, rings, and hardware, then follow the instructions supplied with the rings and scope.
- Tighten the Keystone crossbolts to 65 inch-pounds.
- Tighten the ring-cap screws evenly to a maximum of 15 inch-pounds.
- If the scope manufacturer specifies a lower maximum torque, follow the lower specification.
- Verify that the scope remains properly positioned and that all firearm controls operate freely.
Frequently Asked Questions
What scopes fit these rings?
These rings fit scopes with a 1-inch main tube. They will not fit a 30mm or 34mm scope tube.
When should I choose .990-inch medium rings?
Choose the medium height when the .850-inch low rings do not provide sufficient clearance for the objective bell, barrel contour, scope caps, bolt handle, power-selector ring, or another part of the setup.
Will .990-inch rings clear a 50mm objective?
The .990-inch height is commonly selected for 1-inch scopes with 50mm objectives, but fitment cannot be guaranteed from the listed objective size alone. Measure the objective bell's outside diameter and account for the rail, receiver, barrel, lens caps, bolt handle, and scope controls.
Are these the best choice for a flat-top AR?
The .990-inch centerline is generally lower than many shooters prefer on a flat-top platform. The 1.275-inch high Keystone rings are usually a better starting point when a higher optic position is needed, but the correct height depends on the rifle, stock or brace, scope dimensions, and shooter.
How is the .990-inch height measured?
EGW measures ring height from the top mounting surface of the rail to the centerline of the scope tube.
Do Keystone rings fit Weaver rails?
Keystone rings are designed for Picatinny and Weaver-style cross-slot rails. Verify the dimensions and condition of the specific rail before installation.
Are the rings sold individually?
No. This product includes one pair of Keystone scope rings.
Can I add an EGW Piggyback System?
Yes. Select the appropriate 1-inch piggyback ring cap and the separate adapter plate for the intended optic or accessory. Both components are required for a complete piggyback setup.