Can I Build an AR-15 in Montana?
Woody's answers are based on published federal and state law. Not legal advice. Consult a licensed attorney for your specific situation.
Yes, you can legally build an AR-15 in Montana. The state has no additional restrictions beyond federal law on building rifles for personal use.
What This Means for You
Montana is one of the most gun-friendly states in the country with minimal restrictions on firearm ownership and manufacturing. You can build AR-15s without state permits, registration, or licensing requirements. The main considerations are federal compliance and ensuring you're building a legal configuration.
The Detail
Montana follows federal firearms law without adding state-level restrictions on home builds. You can manufacture rifles for personal use without an FFL as long as you're legally allowed to own firearms and don't intend to sell them commercially. This includes AR-15 platform rifles in standard configurations.
The key federal requirements still apply regardless of Montana's permissive stance. Your rifle must have a barrel length of 16 inches or greater and an overall length of 26 inches or more to remain a rifle. Shorter configurations require NFA registration as short-barreled rifles. You cannot build select-fire or fully automatic firearms without proper federal licensing.
Montana has no assault weapon bans, magazine capacity limits, or feature restrictions that affect AR-15 builds. You can use standard capacity magazines, adjustable stocks, pistol grips, flash hiders, and other common features without concern. The state also doesn't require registration of completed firearms or background checks for private transfers.
If you decide to sell a home-built rifle later, federal law requires the transfer to go through an FFL dealer for the background check unless you're selling to a family member or other exempt transfer. Montana doesn't add additional requirements for private sales beyond federal law, but verify current regulations as laws can change.
Build Impact
Montana's permissive laws mean you can focus on the technical aspects of your build without worrying about state compliance issues. Just ensure your finished rifle meets federal length requirements and you're not planning commercial sales without proper licensing.