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Who are we?

We are a specialty weapons manufacturer and industry resource for Pistol Caliber Carbine products.

All Quarter Circle 10 products are “Made for - Not Modified,” to accommodate the AR15 platform, creating an aesthetically superior look and top rate performance standard.

At Quarter Circle 10, we are dedicated to providing shooters with high quality performance and unmatched customer service.


Headquartered in Dripping Springs, Texas and manufactured in Tucson, Arizona, Quarter Circle 10 was founded around three basic principles.

1.      A love of shooting.

2.      Convenience

3.      and…Cheaper Ammo!

The thought being that by manufacturing a dedicated lower receiver to accommodate 9MM ammunition, one could effectively experience the many benefits of shooting an AR, with the additional benefits of shared magazines and cheaper bullets. Brilliant…right?

But, what should we call the company?

Bettina Jary Mathis, co-founder of Quarter Circle 10, provided the perfect answer.  Quarter Circle 10, incorporating a name, a legacy and an actual brand.

The Brand

The Quarter Circle 10 name and brand are backed by generations of Texan legacy originating in 1854, when George Washington Saunders was gifted 10 calves, branded with a Quarter Circle 10, for his 10th birthday.  The gift led Saunders on a journey of trail driving, minute-manning, rodeo and even politics.

Throughout the generations, a theme of honor, family, country and critter has remained consistent.

The Progression

The lower was made. We did it.  And not to brag, but we did it very well.  In fact, once shooters got their hands on our dedicated lower, they wanted more.  So, we build a bolt. And, then a barrel.  And, then an upper.  They loved all of those too.  We now produce the complete gun.


We build dedicated pistol caliber AR parts, packages and complete guns.  It is what we do.  It is the only thing we do. We do it the best we possibly can. And, we guarantee it to work the way we want our own weapons to work.

We are Quarter Circle 10. We are THE AR Pistol Caliber BRAND.