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Brownells Gunsmith Kinks® - Harrington & Richardson - Revolver Models Trigger Return Spring

Scott Olsen, via email

During my tenure in Gunsmithing, there has been more than one occasion where a trigger return spring has been broken. Using spring bar stock, I attempted to create a new spring once, but it took hours on a milling machine and then kept breaking when I tried to get the right double back curve. Even when the spring was completed, it just didn’t work like it was supposed to.

So, with that said, I recently had a pre-1942 H&R Revolver - Trapper Model in the shop for a spring repair, general cleaning and an inspection for safe use. Let’s get to the spring repair.


Photo 1: Final Spring Assembly

Following are the steps for making the spring replacement:


Photo 2: Spring Arch
  1. Using a scrap piece of steel or copper/brass ranging in thickness from 0.032" to 0.039" cut a piece to fit the notch on the trigger guard as shown in photo #1.
  2. Find a piece of spring stock (from your scrap/miscellaneous parts bin) ranging in thickness from 0.040" to 0.043", cut the length exactly 0.939".
  3. You'll need to install a 6-32 fillister screw (6-32 taps are in a standard tap and die set). Cut (6-32) clearance holes in the trigger notch piece and spring stock metals; make sure that both parts will lie flush with the trigger spring notch back.
  4. To provide separation from the spring base and to simulate the original spring curve, use a small washer.
  5. Cut the 6-32 fillister screw to length, not counting the screw head.
  6. Assemble the pieces to check for fit and, using a rotary tool, grind down any overlapping materials along the triggerguard sides.
  7. Now, disassemble the new spring system to work with the main spring. Putting the screw end in a vise (showing about ½" to ¾" of the spring end). Use a standard butane torch to bring the spring metal to cherry red. Use a ball peen hammer to shape the arch to cause the pressure needed to return the trigger after firing the revolver. Look at the photo 2 to get an idea of how much arch will be needed. To get the final arch at a sharper angle you should be working with just 3/8" to 1/2” of the spring.
     
  8. Reassemble the spring replacement system, use a hand rotary grinding disc to flatten the fillister screw head, cutting the driver slot further down as you go. This will make the screw head very thin but will leave enough surface to hold the assembly together.
  9. Finishing the spring end requires shaving down the end thickness. Starting at 0.269” from the spring end, use a tapering cut (hand grinder) to bring the end thickness down to 0.032" to 0.036” as shown in photo 2.
  10. At his point it’s time for a test fitting to the revolver frame and trigger notch. You will know right away if everything is fitting and retracting the trigger properly. If all is well, you’re done.
  11. However, I’ve found that on the older revolvers that there is too much drag friction from the hammer, trigger sear, and hand assembly to let the trigger reset completely. To remedy this, follow these instructions:

With various polishing wheels and stones, polish to high gloss areas where the trigger sear is going to travel or slide across. This includes the notch where the sear will rest to release the hammer.

Next, polish the trigger sear, the hand, and the hand spring. Ensure that the hand spring path on the sear is polished completely smooth. Go to the frame and lightly file the hand path and opening, making sure all burrs have been removed. Any one of these areas can create enough friction to hamper trigger reset operation.

Lubricate these areas with quality gun grease - and you're done.