Home Forums Hunting & Shooting Gunsmithing Heat Treating Springs

I need some input as to whether I should be heat treating springs or tempering (drawing)or both. The springs are in the picture below. They are trigger reset springs for 22 semi auto rifles and are wound on a simple jig I designed. They are made from Brownells' Music Spring wire.

I am familiar with heat treating and tempering knives made of 1095 and similar steels and I am pretty sure this is a carbon steel as well.

My question is two fold. Should I be heat treating and/or tempering and how. The concern is that the spring may have a short working life before taking a "set" and loosing it "springiness"



Any assistance would be greatly appreciated.

I would contact Brownells and ask if the wire is heat treated and usable as is.

If not, then I would ask about heat treating it.

I would contact Brownells and ask if the wire is heat treated and usable as is.

If not, then I would ask about heat treating it.

13579 your disconnector is malfunctioning.

Vincent, nice, uniform springs. Good job!

Tempering is part of the heat treating process. First, you heat and immediately quench the part to make it hard, then you reheat and quench the part at a lower temperature to set the desired hardness. This is the same heat treat process you would use on knives and basically all carbon steels.

FWIW, when I heat treat small items, I hold the parts over a bucket of cold water with one of my designated and very abused magnetic screwdriver bits, and as slowly and as uniformly as I can, heat the parts until they lost their grip and fall into the bucket of "cold" water. When carbon steel reaches it's upper transformation point, the molecules align at a point where there is no magnetic influence.

It is at this point that the quench must take place in order for the part to be it's hardest. After the part is hardened, I polish the piece so that I can watch the parade of colors dance across the part as I carefully reheat the part. A spring is drawn to about a dark blue color.

That type of spring made cold from music wire should be good to go as is. Typically you're not stressing such a spring very much. Be sure the spring is strong enough to reset the trigger when the mechanism gets dirty and gunky.

Mine seems to work pretty well with no heat treating



although I like your lighter one better, it's kind of like a single set for the 10/22

I suppose I should complete the answer, music wire springs are typically stress relieved at 350 - 450 degrees F. for maybe an hour depending on mass and process. Can't overcook at those temperatures. But for a trigger return spring I can't imagine approaching the metal's elastic limit (set problem) even with retained stress.

Aw.... now you went and let the cat out of the bag.

The .024" really only works on the best tuned and much polished trigger assemblies. I have one trigger that has gone about 500 rounds with a 1.0 to 1.2 lb pull and passes all safety tests The .032" works pretty well on any moderately polished set up but can start to hang up if things get dirty. Good for about a 1.3 to 1.6 lb pull using Volquartsen Hammer and an adjustable sear. The .039" is dead reliable so far and good for a 2 lb trigger with the same parts.

I am trying to learn all I can about these springs. They are currently being tested in about 6 different peoples 10/22 rifle for feed back. So far so good.

Your trigger group needs more attention. Remember to to only use dry lube like Rem dry lube teflon in it.