Percussion lock mainspring question

[Larry (Omaha)]

Have a little percussion rifle I put it together in the 70's. I never shot it much, but lately, decided to improve some of the flaws it had. At this time I will only discuss one. The cocking effort was waaaaaay too stout. I thinned the mainspring in two areas. The main leg that connects to the tumbler, (thickness) and the whole spring width ways. It came out to my satisfaction, but I wondered where it really should be according to any stats out there.
It is around 10 lbs now.
Flintlocklar

 

[plmeek]

I don't know if you can reduce it to a single number. The mainspring needs to be strong enough to consistently pop a cap and resist the blow back force so that it doesn't move the hammer back to half ****. Some may like it strong enough to hold the hammer and cap on the nipple to minimize hot gases and particles hitting your face. The nipple can influence things since a worn and enlarged nipple will allow more hot gases to blow back.

 

[LawrenceA]

I am sure people with more experience will pipe up but in my humble experience..
A percussion lock is not as dependant as a flintlock on spring power as all it needs to do is possibly push the cap down, a little, and crush the priming compound.
It does not need to scrape steel shavings or the like.
Based on this the affects of weakening a percussion Mainspring would be:

• less stress/wear on lock components;
• less stress on lock mortice;
• as you mentioned easier to ****;
• slower lock time (wouldn't notice);
• less reliable if using bad fitting caps;
• As plmeek said about gasses;
• less chance of nipple damage.

So really, as long as the lock is still reliable then no real problem.

 

[Phil Coffins]

That’s an interesting question, I measured a couple in my parts drawer and one for a revolver is 120 grains and a V spring for an unknown lock is 250 grains. But then I tried using a scale on a double barrel ml shotgun and to full **** got 9.5 lbs and 15 lbs . But I agree with others there’s a lot more involved then just weight of pull.

 

[LawrenceA]

That’s an interesting question, I measured a couple in my parts drawer and one for a revolver is 120 grains and a V spring for an unknown lock is 250 grains. But then I tried using a scale on a double barrel ml shotgun and to full **** got 9.5 lbs and 15 lbs . But I agree with others there’s a lot more involved then just weight of pull.

You are right.
Thinking about t I have a couple of doubles and the hammers vary considerably between barrels.

 

[Larry (Omaha)]

I don't know if you can reduce it to a single number. The mainspring needs to be strong enough to consistently pop a cap and resist the blow back force so that it doesn't move the hammer back to half ****. Some may like it strong enough to hold the hammer and cap on the nipple to minimize hot gases and particles hitting your face. The nipple can influence things since a worn and enlarged nipple will allow more hot gases to blow back.

Not looking for a single number, just ballpark as I know every gun is different. Blow back is an issue that I never considered , but I shoot my flinters 98% of the time anyway. This is a short little half stock 45, and I don't think that will be an issue. If it is, I can V out the front of the hammer nipple cavity. ( no idea what that is called)
Thanks for the reply
Flintlocklar