Project Blade Runner
Next I turned down an aluminum cap to plug the moon-shaped cavity in the end of the Steyr receiver where the original rifle barrel threaded in, again copying the necessary details from the stunt prop. I made this component a two-part assembly, with the small center bead as a drop-in part.
The final critical detail on the receiver was to recreate the actual Steyr serial number from the original hero prop. Our new casting obviously had a different serial number, so I milled a slot into the "hero" receiver and then carefully sanded and fitted a drop-in serial number plug from my best copy of the stunt prop.
Now that the Steyr receiver had been successfully mounted and the pistol frame details worked out, it was possible to finish fitting the side covers to the prototype. With the swing arm installed and the cylinder set in the proper position in the Bulldog's frame, I proceeded to fabricate a cylinder rod out of several pieces of brass tubing by soldering them together.
The two side covers had to fit over the cylinder and allow it to turn while also matching the proper placement and shape of these parts relative to the stunt prop. It took many days to shape and carve these parts out.
From study of film scenes and the stunt prop, we could see two holes positioned in a vertical line at the front edge of the left side cover. (Note that the stunt copies seem to have had the bottom one clayed over.) When the cover is properly aligned over the frame, these two holes were found to line up right over the cylinder swing arm. Thus, the left cover could be mounted to the swing arm and could then swing open with the cylinder. This arrangement was no accident, as it allowed easy reloading of the hero prop on the set. We wanted to recreate all the functional details of the original, so the same design was incorporated into the model.
As I worked with the cylinder in the revolver, it became apparent that a spring was needed to hold the cylinder latch rod in place. This necessitated the addition of yet another ring of cut tubing, which was soldered into place to hold the locking spring. All in all five sections of tubing had to be spliced together to make this one rod.
Next came the working trigger and hammer. From the stunt prop it was evident that the Steyr receiver had been cut to fit around the revolver frame, including removal of a section at the rear to allow the hammer to drop through. But it was also evident that the Steyr's rear bolt cap was uncut, so the only solution to fitting all the components was to "bob" the hammer. Charter Arms did offer a factory bobbed hammer as an option, but the factory piece is still too large. Either way, the propmaker had to cut down the Bulldog’s hammer to spare the bolt cap and have everything work properly. Following suit, I bobbed the recast hammer to clear the end cap.
Using a cut away pistol frame, I studied the working of the trigger and hammer actions carefully to recreate them in the model. I found that the Bulldog hammer has a small spring loaded lever that the trigger pushes on to the throw the hammer back, and that for the trigger to return to the fire-ready position, it had to stroke by this lever to get below it again. This lever had to be able to allow the trigger to pass, and then it had to spring back in place so that the trigger could engage it again. Prototype testing demonstrated that the cast polyurethane was not strong enough to withstand this pressure when cast to the same dimensions as the steel part, so I was forced to both thicken this lever as much as possible and to recast it out of epoxy.