Hi Scota,
Good on you for making the new parts that allow for an automatic pan opening. Historically not all wheellocks did that. On some, you had to slide the cover forward before firing, others you pushed a button that slid the pan forward, others were fully automatic, and lastly some had the button and automatic feature. I assume the latter locks were an admission that reliability was greater when the pan was slid forward before shooting. The dog spring must be strong but more important, the toe on the dog must be shaped properly so that the dog will continue to move downward as the pan cover slides forward. Sometimes, on poorly made wheellocks, the dog gets hung at the position it was when the pyrite was pressing on the pan cover and does not move down when the cover slides forward. That would mean no sparks. It is a skilled balancing act to get it right. I urge you not to change the distance the wheel rotates or the strength and thickness of the mainspring. The mainspring must be very, very strong so that as powder fouling and flash escape from the grooves in the bottom of the pan and build up behind the wheel, the mainspring can still rotate the wheel against the fouling. The short throw of the wheel also helps prevent jamming. You do not need much rotation to produce good sparks if the pyrite is good and the springs properly balanced. This is why wheellocks did not make good military weapons. Also tell you client not to use 4f powder for priming. Coarser powder is less likely to fall down behind the wheel if the grooves in the pan are not precise and are sloppy.
dave
