How to modify the Spencer mainspring???

[Dakota Widowmaker]

For folks that have lightened their mainspring for their spencer carbines, what does your finished product look like???

Are you just modifying the bottom that works the trigger or the top that works the hammer???

Do you "hourglass" your spring or just work on one side?

I did the screw and loctite trick and it helps. But, I'd still like to get the spring down quite a bit more. I figure I am at around 12lbs.

Should I also stone the sides of the parts or leave them raw? (they are pretty smooth already)

I do have an extra spring on order just in case I screw it up...

Oh, and I found the screws on the plate for the firing pin were WAY loose.

[Two Flints]

Dakota,

If you haven't already, check the ORI Thread on page 1 and especially the post in this topic/thread by Grapeshot:  http://www.cascity.com/forumhall/index.php/topic,2906.0.html

Two Flints

[Dakota Widowmaker]

Yup, I reread it a few times...

Thinned the trigger/bottom of the spring a fair amount and put a taper on it as well.

then, I narrowed it down from front to back. (leaving the side that faces the lock plate untouched)

I then polished it all up with some 400 grit and used some mil-tec on all of it with a heat gun.

I would remove a bit of metal, quench, grind some more, quench...etc.

VERY different feeling to the Spencer.

[red coneston]

I narrowed the trigger portion and made the pull lighter on mine, the drawback now is unless the gun is pointed down when you put it on half cock the sear doesnt allways seat well in the notch and it may be fired  from this position by pulling trigger also. Guess its something with the fly. I need to figure how to keep the lighter spring and make the safety position reliable.
Red

[Dakota Widowmaker]

I was able to lighten it enough so that everything still works.

I think the sear/engagement surfaces could use a bit of Flitz on the end of a popsicle stick to smooth them out.

Also, loosening the screws on the plate that holds the whole setup together and then using some loctite blue on it made a world of difference.

I mainly reduced the thickness of the spring on the bottom, and only in front of the positioning screw that keeps the mainspring in place.

Trial and error and working slowly is what I did. I probably reseated the spring a half dozen times to test out the action.

I MIGHT give it one more session with the dremel and then polish it all up.

Now that I have EVERYTHING working smooth on it, I am less inclined to tweak it too much more w/o darn good reason.

I have another mainspring on order and I will do a "before/after" pic along with dimensions of what my final product looks like.

For now, though, I am pretty happy with my results. Still have all 10 fingers and 10 toes, two eyes, two ears, and a nose.

[red coneston]

You got me thinkin so I got my rifle out  and the half cock engages well most of the time even with barrel up.
The sometime poor engagement may have even been there before I thined the spring and I didnt notice
until doing the testing. Your idea of polishing with flitz sounds good, I'll try it and maybe get it 100%