DIY Rifle Barrel Bounty

Current Prize Pool: 1000 USD + ammo proving costs

This is our first ever bounty, but hopefully more to come.

To win, you need to agree to release[1] fully open source[2] and document the process[3] of making a rifled, intermediate or full-power rifle cartridge barrel. The barrel must be chambered. The cartridge you choose must be bottlenecked, and must be on this list: 5.56 NATO, 7.62 NATO, .300BLK, .30-06, 7.62×39, 7.62x54R. The barrel must be between 12 inches and 24 inches in length. The materials you use in the barrel don’t matter, as long as it can last the 200 rounds mentioned below without signs of failure or fatigue and weigh less than MAX_WEIGHT. Here, MAX_WEIGHT = 6lbs for intermediates (5.56 NATO, 7.62×39, 300BLK) and 8lbs for full-power cartridges (7.62 NATO, 7.62x54R, .30-06).

You need to document the process[4] of shooting 200 rounds out of a single barrel. How you exercise the barrel is up to you – you can create your own single-shot design around it, use a pre-existing platform, etc, whatever works.

The 200 rounds must be currently available factory supers – they cannot be handloads or subs. This is to ensure we are hitting normal pressures and can reproduce the results using standard ammo available at a gun store.

Whatever process you choose cannot use tools unavailable in countries where gun parts are regulated (barrel blanks, rifling buttons), or what we’ll call “machinist” tools – things you couldn’t have in a dorm room or apartment, like a drill press, lathe, mill, etc. Your total tooling and BOM costs cannot exceed 1000 USD, not including the 3d printer. You may assume the audience owns a well-tuned consumer-grade FDM printer with 256mm x 256mm x 256mm build volume and can print in any common filament used in guncad (PLA(+), ASA, ABS, common Nylon blends), TPU or PETG.

If you succeed and are the first, you will win the main bounty which is currently 1k USD + the cost of the ammo you used to prove the design. This will increase by whatever amount other people donate to the bounty pool. To donate, INSERT DONATION INFO HERE – still needs to be finalized, report back later.
This money is payable however you like, current options are Monero or Bitcoin. We will try to figure out other options at a later date.

If you have an approach that succeeds on almost all fronts but fails to meet every rule, we will have a second smaller prize for that, called the Penrose prize. Extra points if the rule you break is the bottleneck rule and you make it in 350 Legend. If you think you are aiming for this, please reach out to us to see if your idea can potentially work, contact info mentioned below. The tooling rule and rifle cartridge rules are excluded from this though – if you have a mill and lathe, obviously you can do anything you set your mind to, and pistol calibers already are unlocked via ECM.

A very special shoutout to Memphistopheles, as he was the person that first suggested this idea and inspired us to start looking into setting this up.

Some final notes:

Don’t try to rules lawyer this. The goal is to unlock a new technology for this community that lasts forever and everyone benefits from, not to make easy money. We will be happy to reject entries that are “cheating” to win in some way, and not legitimately trying to solve the problem.

Second, anyone who participates needs to understand that you are fundamentally doing research here, not building a pre-tested design.
Assume that catastrophic failures can happen, and that they will be as horrific as you can imagine.
Be safe, this is not encouragement to win a Darwin award.
You are assuming responsibility for anything unsafe and dumb you are doing here.

Finally, these rules are still subject to change, as this is still in its infancy. Please reach out to with questions or visit the OOB Discord/Matrix server:

Have fun and good hunting.

[1] Release can be on the platform(s) of your choice, or can be handled/aided by us. It should preferentially include Odysee.

[2] Fully open source means the design CANNOT be patented, and MUST be released as public domain or an OSD compatible license. If you don’t know what this means, we will help you choose a license to package with the release. NOTE: Non-commercial Creative Commons licenses ARE NOT OPEN SOURCE.

[3] The documentation must be sufficient that a reasonably intelligent dev or beta tester in guncad can FULLY REPRODUCE your process. If you are having trouble on this section, reach out to us and we will help you prepare documentation.

[4] You DO NOT need to release any doxxing video, nor record everything. This is partly honor system based, but you will need to send us some proof.