Where Limits End. Precision Begins.

What makes 51Fifty rifles different from other AR platforms?

Every 51Fifty weapon system is engineered from the ground up—not retrofitted from old designs. Built for warriors, competitors, and peacekeepers who demand the best, our platforms feature:

• Patented Rapid Action Cam (R.A.C.) – Our patent-pending R.A.C. system eliminates traditional takedown and pivot pins, replacing them with a precision cam lock that secures the upper and lower together. This design eliminates the typical AR “rattle,” increases system rigidity, enhances accuracy, and allows for lightning-fast breakdown and maintenance.

• Synkro™ Ambidextrous Control System – This is not a bolt-on. Synkro is a true mirrored ambidextrous control system with rack-and-pinion internals, cassette-style installation, and identical feel, function, and actuation pressure on both sides. The lower receiver is built around it—no compromises, no imitation.

• TriLok™ 3D Clamping System – The world’s only scope mounting technology that meets STANAG and Picatinny spec exactly. Our TriLok mounts offer unmatched clamping force, rock-solid zero retention, and a return-to-zero standard unmatched by any competitor.

• ZeroLok™ ARCA Rail Handguards – We were the first to offer full-length, integrated ARCA Swiss handguards as standard. Originally developed for photography, ARCA has become a must-have in ELR/PRS and tactical shooting for its rock-solid mounting and rapid position changes—perfect for barricades, tank traps, and field use.

Can I use a 51Fifty upper or lower with my existing AR platform?

No. Due to the integrated design of our R.A.C. system and the dimensional changes to our upper and lower receivers, 51Fifty components are not cross-compatible with traditional mil-spec setups. Our platform is built for performance, not compatibility with outdated tech.

What kind of accuracy can I expect?

While accuracy ultimately depends on the shooter, our rifles are designed and tested to deliver elite-level precision. Depending on the series, you can expect sub-MOA to ½ MOA performance or better with quality ammunition and optics.

Do 51Fifty rifles require a break-in period?

Yes. Like all precision firearms, a break-in period ensures optimal performance. We recommend lubricating with CLP and running at least 100 rounds through the rifle to properly season the barrel and bolt carrier group. Detailed break-in procedures are available on our website.

What is ARCA and why is it on your handguards?

ARCA (aka ARCA-Swiss) originated in the photography world but has been adopted by the shooting community—especially in ELR, PRS, and tactical competition.
It allows seamless mounting of compatible bipods and tripods, and enables rapid position adjustment without disconnecting gear. Our ZeroLok™ ARCA handguards provide a stable, flat interface that excels on barricades, tank traps, and other field obstacles.

Where are your rifles made?

Every 51Fifty firearm is designed, manufactured, and assembled in the USA using American materials and state-of-the-art manufacturing processes.

Do you offer Law Enforcement or Military discounts?

Yes. Active and retired Law Enforcement and Military professionals qualify for exclusive pricing. Contact us directly with your credentials to get started.

Can I buy directly from 51Fifty?

Yes. You can order directly through our website or work with an authorized 51Fifty dealer. For agency orders or high-volume inquiries, contact us directly.

What is the warranty on your rifles?

We stand behind our work with a lifetime warranty on manufacturing defects. If something goes wrong due to our craftsmanship, we’ll make it right. No excuses.

What mounts and optics work with your rifles?

Our upper receivers use standard STANAG/Picatinny rails, allowing compatibility with a wide range of optics. For the best possible performance, we recommend using our TriLok™ Scope Mounts:

• Defender – Cantilever design for tactical setups

• Predator – Low-profile for hunters and bolt-actions

• Pinnacle – High-profile for precision shooters

Need more info or help?

We’re here for it. Visit our Contact Page and our team will respond with fast, knowledgeable support.