How a military veteran invented a new part, filed for a patent, and started a company in his basement with a benchtop lathe.

by Andrew Cozad

First designed by ArmaLite before it was sold to Colt in 1959, the AR-15/M16 design has been around since the late 1950s. After it was adopted as the standard small arm by the U.S. Military in the early 1960s, the weapon has undergone a number of changes and upgrades to improve its overall firing and handling, which has included alterations to its stock, optic sites, rails, grips, triggers, and recoil buffers.

In 2018 I started Cozad Manufacturing to develop and sell my contribution to the improvement of this weapon system with the release of the M-18 model mechanical recoil buffer. This improved recoil buffer mitigates firing recoil of the weapons and aids in sight alignment. It also reduces the rate of fire in select fire weapons to give the shooter more control of rapid follow up shots in multiple target shooting scenarios. In addition to being the owner of Cozad Manufacturing, I am an Army Reserve Soldier and former law enforcement firearm instructor with over 20 years of firearms handling experience, including two deployments to Iraq and one to Afghanistan as Military Police.

The Idea

The idea behind my buffer was a process that spanned several years. While on my second deployment to Iraq, I bought a hydraulic buffer for a new 6.8mm Remington Special Purpose Cartridge AR-15 I had waiting for me at home. I knew the 6.8 would have a little more recoil than the standard 5.56 and hoped to make the 6.8 handle the same. However, my first test firing of the hydraulic buffer for the 6.8 gave an unsatisfactory initial performance. I discovered the bolt would short stroke the magazine using the hydraulic buffer and as a result, the bolt would not fully cycle and lock back on an empty magazine. To counter this problem, I installed an H1 buffer and left the hydraulic one out. This was the beginning.

In 2017, one of my friends asked me if it was possible to make a barrel for an AR-10 chambered in .45-70, a cartridge designed to shoot 405 grain bullets. I told him that I didn’t think this was possible due to being a rimmed cartridge, however, he later showed me a company online that had successfully done so. With this as my point of reference, I was able to build one, finishing it in late March of 2018. This project was another push for my M-18. During this process, I began to think of a way to reduce the recoil of the massive .45 caliber bullet by designing something that was indestructible, affordable, and capable of handling a variety of ammunition types and bullet weights.

My First M-18

The initial design for my buffer was built for the AR-15 A2 rifle model and took only a couple hours to make. I used a recoil spring from a Beretta 92, some random aluminum, and some small hardware from around my basement. The following day, I conducted the first test firing of the prototype and was impressed by how effective it fired on a target 100 yards away before the buffer broke where the spring rides on the operating rod. This first test fire proved my design was effective and also identified weaknesses to be improved upon. I kept plugging away on the design in my basement workshop.

Several months later, after several design and material changes, I found the right combination of both. Using the new and much-improved design in test firing, I successfully fired hundreds of rounds through the rifle using only the buffer with no return spring. I was amazed at how well the buffer held up on only the second prototype model with no damage to the rifle or buffer noted. I then set out to prove the multi-caliber capabilities in 6.8mm, 6.5mm, .300 Blackout, 7.62×39, several 5.56 variants, and 9mm to make sure the buffer worked and fired successfully in a variety of chamberings. The third test phase of the buffer prototype tests was used with select fire weapons which I had successfully carried out at Veronisi Gunworks in Seminole, Pennsylvania, a licensed Class Three dealer.

My M-18 series of buffers works by reducing the recoil impulse caused by the reciprocating mass of the bolt carrier assembly. By adding an additional 10 pounds of spring tension at the last 3/4” of travel of the bolt carrier, the M-18 turns the stock recoil spring into a two-stage type. This greatly reduces the perceived recoil and dramatically reduces rates of fire in select fire weapons. By slowing the sudden stop at the end of the recoil cycle, the M-18 also reduces shock to any mounted accessories and optics. Built using high grade aluminum alloys, stainless steel, high strength alloy steel, and tungsten alloys, I designed these buffers to last. All aluminum components are hard coat anodized and all steels are heat treated. Unlike hydraulic buffers, Cozad buffers do not have seals or fluid to break or leak out. If by chance the buffer fails, it is easily fixed.

When it came to naming my buffer recoil model, I decided on M-18 for the year of the completion of the model. The K in its name stands for carbine model and G for rifle model. I kept the H designations for the various weights of the carbine model. In September 2018, I filed for my first patent on the M-18 series of buffers and in April 2020 the patent was ready to be issued. Over that year and a half I had a lot of correspondence with the United States Patent and Trademark Office and was very excited to have my first patent issued.

Currently the M-18 is available in two models for the rifle and carbine length stock extensions. The carbine model is available as the M-18k and comes in weights of 3, 3.5, 3.9, and 4.6 ounces. This enables the end user to choose the weight best suited for their individual carbine. Future offerings will include a dedicated pistol caliber carbine model as well as a model for the Barrett M82-series (M107) .50 BMG rifles.

I started my company with an idea, a basement workshop, and a benchtop lathe. That led to successfully filing for a patent, creating a Limited Liability Company, and a full-fledged company (CozadManufacturingLLC.com, 814/516-6359) marketing several products based on my design.

Read more in the September 2020 issue.

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