Hi Gang,
Took my newly acquired 336 in 30-30 to the range today and started having misfires. Luckily, I had a 94 and a Stevens 325 with me & they shot the misfires just fine. When I got home, I pulled out my drawing & found a "hammer-spring adjustment plate" which, I discovered, could be shimmed away from the tang to increase tension on the hammer spring. It seems to work great now as I popped some primers off to test it out. My question is...is this the way to tighten the spring or should I just up & order a spring. Anyone done this before?

Have they changed the design of the 336 recently? All the ones I have ever seen weren't adjustable; just put the spring in and set the plate in the grooves in the top and bottom tang and you're done. I guess it might be possible to put the plate in backward, but it'd probably pop out. If it's not reliably igniting primers I'd replace the spring for a new one.

Hi Nobade,
This thing has a plate that fits into a groove on the lower tang and the top part of the plate runs parallel with the upper tang for a distance of about 1/2". When you pry the parallel part away from the upper tang, it pivots from the bottom and the center part of the plate moves to tighten the spring. I put the shim between the tang and the flat part of the plate and the spring gets tighter. The inside of the stock flats hold the shim in position. It's called the "hammer spring adjusting plate" (from a drawing from Marlin on model 336CS).

Newtire, how thick is the metal that you use for the shim. Muffin.............

Hi Muffin,
The shim I used was approx. .030" by "eyeball mic" method. It could be thicker I suppose as long as you don't end up stacking the spring-coils before the hammer is back all the way.