Allen Engineering Mk12 SPR Collar and Adapter

6.8mm (Ops, Inc. #12 Model - Short Collar Original)

The Allen Engineering Mk12 SPR collar and adapter for 6.8mm is a precision-engineered component essential for authentic Mk12 SPR builds and other precision rifles and optimal suppressor performance. This product is from the depths of Ron Allen's workshop, the original engineer behind the Ops Inc. collar and suppressor system.

This collar and brake combo is perfect for rifles of 6.8mm, 6.5mm CM, as well as 5.56mm.  The added aperture is perfect for versatility across platforms.

Key features:

• 100% genuine Allen Engineering product
• Hand-built by the original Ops Inc. engineer
• Designed for 6.8mm and 6.5mm rifles
• Compatible with Ops Inc. style suppressors
• Precision-machined for optimal suppressor alignment

The 6.8mm AEM brake included in this set offers versatile performance. When used without a suppressor, it effectively reduces recoil and muzzle climb while eliminating vertical blast. The brake's design allows for seamless integration with a suppressor, maintaining accuracy and function across both configurations.

It's important to note the critical role of proper tolerances in suppressor alignment. Ron Allen has observed baffle strikes caused by inferior collars or improperly executed barrel profiles, underscoring the importance of using genuine components for optimal performance and safety.

Technical Specifications:

• Material: Stainless steel
• Thread pitch: 5/8 x 24
• Brake overall length: 2.125"
• Designed for precision 5.56mm, 6.5mm CM and 6.8mm rifle builds

This Allen Engineering collar and adapter represent the gold standard for Mk12 SPR enthusiasts and precision rifle builders who demand authenticity and peak performance from their firearms and suppressor systems.

Included is the complete kit:  Collar, flash hider, thread protector, spacer and shim kit.

Note:  One picture shows the comparison between long and short collars.