UBML – Ambi Magazine Release for Restricted States

To me, its sad that a product like this has to exist in the first place, but exist it does. The UBML, an apt shortening of “Ultimate Bilateral Magazine Lock” is a ambidextrous pair to the “bullet buttons” required by states or countries that various restrictions on self-loading rifles.

Thordsen Customs (who also makes a great pistol buffer tube) is now on Generation II, which features the usual technical specifications for rugged products. The UBML is machined from 6061 anodizing and mates to a slightly customized standard magazine release. Finished in Type III hard black anodizing, its battle-ready (or as battle-ready as a magazine release that requires a tool could be).


Basically, it adds the same “bullet button” functionality to the left hand side of the rifle, of which “Competition shooters and tactical training junkies can benefit greatly.” (Another personal shudder…). But, it certainly has practical implications for letting the off-hand easily swap out a magazine.

The kit is compatible with forged and a few billet receivers, but Thordsen Customs does not explicitly claim compatibility with any specific model. The UBML is compatible with most aftermarket bolt catch devices including BAD Levers and their associated derivations.


Retail for the kit is set at $54.99 (which is at least better than a Norgon for us in non-restricted states). Armorer knowledge and tools are required for installation.

Nathan S

One of TFB’s resident Jarheads, Nathan now works within the firearms industry. A consecutive Marine rifle and pistol expert, he enjoys local 3-gun, NFA, gunsmithing, MSR’s, & high-speed gear. Nathan has traveled to over 30 countries working with US DoD & foreign MoDs.

The above post is my opinion and does not reflect the views of any company or organization.


  • TheNotoriousIUD

    “Tactical training junkie”, good God those people are annoying.

    There is an excellent organization out there that provides such training, provides weapons, ammo and housing and all at no cost to you. Its called the Marine Corps.

    • Marc

      With the added benefit of quite possibly getting blown to pieces.

      • Marco Antonio Gonzalez

        Do not forget citizenship

        • TJbrena


        • Hensley Beuron Garlington

          Brought to you by the United Citizen Federation!

      • Phil Hsueh

        Not necessarily, it all depends on your MOS and the vast majority of Marines will never hear a shot fired in anger. You do realize that in the modern military for every trigger puller out there there’s probably 10 people back on the FOB or State side supporting him with more of chance of being killed by a drunk driver than being blown up by an IED.

    • USMC03Vet

      no cost to you*

      *sanity not included

  • Hensley Beuron Garlington

    Stupid gun control nuts. Got you bullet button right here.

  • Tet

    Wait a second…. There’s other states beside California that uses bullet buttons?

    • Anonymoose

      New York, for one. Pretty sure CT is that way too.

  • USMC03Vet

    Government regulation solely to piss off citizens that dare exercise their rights. If being able to load a magazine was such a public safety concern law enforcement would have to abide by the same asinine restrictions considering they are the ones involved with most shootings to begin with.

    Button buttons = cuckolding a firearm

    • Martin Grønsdal

      Is it allowed to attach a device that circumvents the bullet hole? Like a needle always there?

      • Anonymoose

        No. The law says you must use a separate “tool” to remove the magazine.

        • Martin Grønsdal