doublegunshop.com - home Forums General Discussion DIY Gunsmithing @ doublegunshop.com Lefever Main Spring Retainer Block

Went into Shotgunworld with Pale Moon, sorta jumbled, but it does work.

Anyways, the user "Beerbatter" mentioned fabbing a "Lefever Main Spring Retainer Block" based on a concept that he saw online. No link to the source where the block is described. The images in the post say "Image" but there is no link.

From Beerbatter on Shotgunworld Jan 30, 2016
"Ithaca Lefever Nitro Special Firing Pin Broken"

UPDATE: Wow, trying that direct link with Pale Moon gets some unending activity that never resolves...


"Hey folks, I'm back. Here is what I fabricated based on the concept I saw on the Internet.

Image

It bolts to the receiver using the two threaded holes for the trigger plate. I chose to use two screws instead of one to secure it based on my failed experience with the C-Clamp method I tried previously, discovering that these springs are super strong. The two cap head screws are at an angle and push against the main spring caps, releasing the pressure off of the hammers so that the hammer pin can be easily removed.

UPDATE: This is an image from the earlier C-clamp method. You see the two screw holes in the bottom of the frame.
Nitro Special frame exposed

Image

Then I backed off the cap head screws slowly to relieve the spring pressure. I stuffed a rag into the receiver to catch the spring caps and springs as they pop out once the cap head screws clear the main spring caps. Worked really well. This fixture won't work to re-install the springs though. I'll make something different for that."

Here is Beerbatter's initial attempt with a C-clamp and lots of gumption... [on Internet Archive]
LeFever Mainspring Compressor

I made a block (aluminum) that screws to the action using the bottom plate screw hole, and two set screws at an angle to engage the followers & retain the compressed mainspring(s) and followers.
Works nicely.
You need to make a push rod to use to compress each spring and follower deep enough so the set screw will jam the follower in the mainspring hole.
I set the whole thing up in a Mill/Drill using the vise to hold the frame and the quill to compress the springs. I can lock the quill in any position to hold the spring follower compressed
as I tighten the set screw.
But usually just hold the quill down and turn in the set screw with the other hand.

Simple enough but use some care in compressing the spring w/follower. Make sure the rod is squarely in line with the follower and spring and help guide it down into the frame a ways with a gloved hand/fingers.
The spring while initially being compressed w/the follower can kink suddenly to one side and the follower w/spring disengage from the pushrod. The parts go free & flying off into areas of the shop heretofore unkn.

Once compressed and held in place with the set screw, the push rod is retracted. The hammer is then dropped into the slot in the frame and lined up with the pivot hole. There is no spring tension on the hammer when doing this so the hammer can be pick up easily thru the side with a tapered punch and the pin started thru the frame and hammer to secure it and into the center section of the frame.
Then do the other side as well before releasing the spring tension on either side. Keeping the spring tension off of the hammer(s) allows the pivot pin to be easily driven into place.

My Sieg X3 has been unused for too long... Interesting part about the mainsprings kinking. A possible way to get around that is to use a loose length of DOM tubing around the rod used to compress the springs. That way, the mainspring cannot kink.

Once upon a time, I removed a notch rear sight off a Ruger P85 MKII and the firing pin safety spring launched into history...

Looking at the hole for the top lever bolt, that would be a hella stout place for a shaft to take up spring thrust. But there isn't much width left to secure a shaft without extending the block over the hammers. Unless it would be a smaller shaft that bears against the rear of the bolt recess. Eh, probably way too over-engineered. Two screws into the existing threaded holes in the frame should be enough to hold the mainsprings... Rube Goldberg, where are you?