Help forming US 1816 Musket frizzen spring

[fourbore]

I have determined this frizzen spring will need to be hardened and annealed. I started with a casting of spring steel which I will assume is 6150. I have all the temperature requirements from the ASME website. What I dont know, is how much of a set this spring will take on after initial install. I also do not know what, exactly is the corrected extended size for the spring. To be clear, do I need to expand the spring more than the 3/4 inch shown prior to hardening? Once I set the spring in the gun and compress it a few times how wide should it settle down. At this point, I am not asking procedure. I am asking for physical dimensions before I harden this. And how much will it set in use. That is if I took it off the lock after a few cycles what size should it be?

I am feeling a little frustrated --- really, appreciate any help. Numbers would be great.

The photo was a casting. It is now filed and fitted.

 

[fourbore]

This maybe a better photo (full disclosure 1812 spring on an 1840 lock):

 

[Sam squanch]

A frizzen spring will not compress much compared to a mainspring. I would leave it as is, temper it, and try it. If you think it’s not strong enough, you can always try it again, and just open it up a little.

 

[Sam squanch]

Maybe someone out there has an original spring you can measure

 

[fourbore]

Well, I hardened and annealed the spring, without any bending. I was worried it might be too loose. No worry there. It is very strong. I mean very.

Thanks, Sam.