Challenge Lock Requirements
From LPUinfo
A "Challenge Lock" is defined as:
A commercially made lock and working key that includes a minimum of SIX modifications by the lock builder. Number of modifications must total or exceed SIX and may include any or all of the following:
- Turned, sculpted or shaped key pins
- Turned, sculpted or shaped driver pins
- Modification to the chambers by threading or counter-milling
- Improvised secondary locking mechanism
- Distinguishing mark engraved into the lock
- Hand cut key
Stipulations:
- Each "turned, sculpted or shaped" key pin counts as one modification. Pins must be shaped BY the builder, removing no less than 15% of the original material
- Each "turned, sculpted or shaped" driver pin counts as one modification. Pins must be shaped BY the builder, removing no less than 15% of the original material
- Pin-in-pin counts as one "turned, sculpted or shaped" pin per pin modified. Shaping a pin and also making it pin-in-pin does not count as two modifications
- Chamber threading counts as one "modification" regardless of the number of chambers augmented
- Chamber counter-milling counts as one "modification" regardless of the number of chambers augmented
- Each improvised secondary locking mechanism counts as one modification (latches, check pins, etc.)
- "Distinguishing mark" engraved into the lock counts as one modification (Simple scratches do not count. Engraving must be a symbol or mark of the maker)
- Hand cut key counts as one "modification". The key must be cut using hand tools from a blank, and must be a reasonable bitting. Locks made with 0-bitted, or minimally bitted keys do not count.
