Large Siler

[elk killer]

I was gifted a large Siler flintlock, by a friend's widow,
It had been stored forgotten in a drawer for the last 12 years
the whole time on full cock, it works fine, seems new untouched
would their be any concerns on being full cock for so many years?

[D. Taylor Sapergia]

It is possible that the spring may have lost a bit of its power.  Just to be sure, buy a replacement spring, and see if there is any difference.

[Daryl]

Just the main spring.  It is unlikely the feather spring nor the sear spring would 'take' any 'set'.

[Pukka Bundook]

If it sparks well, that's all you need.  Just try it out and compare with another lock if you have something around. 
Best,
R.

[M. E. Pering]

I have heard several opinions on this, but the most credible I have heard is that a spring won't loose it's set by being compressed.  It is working the spring over several thousand cycles that makes it slowly get weaker.  This explanation was given by a relatively famous gunsmith in England, who was doing a lecture on spring making.  But as D. Taylor Sapergia suggested, it wouldn't hurt to get another spring to compare to this one.  Nothing wrong with having an extra spring for it lying about, so not really a waste.  Keep in mind, though, that it is a rather loose comparison, since you don't know how strong the original spring was to begin with. 

M. E. Pering

[elk killer]

I'm sure Jim Chambers would know
But was there any thing different from
Today's  mainspring as to a 12 year old spring?

[Pukka Bundook]

Elk Killer,

That's the interesting part;  Were the springs exactly the same 12 years ago anyway??
For what it's worth, the normal sidelock ejector shotgun, made pretty much the same since the last half of the 19th century, has mainsprings  that many folks never bothered to de-cock, and still work as well as ever.  It Sounds bad, leaving something fully cocked, but maybe not as bad as we think?

[M. E. Pering]

Of course, you could always ask Mr. Chambers about it.  But the most practical solution is to see how the lock sparks, and check it's speed... If you have doubts, just replace the spring.  I have also re-hardened and re-tempered springs, but not in a gun lock.  I have made a couple of mainsprings for gun locks, but that was from new steel, which is different.  And it was 1095 spring steel, not a cast spring.  I have no experience re-doing cast springs.

I do things in a pragmatic way though... If the spring works well, use it.  If not, replace it.  Of course, I would still experiment with re-hardening and re-tempering if it were mine and was found lacking.

M. E. Pering