Steel to make firing pin?

Note that when you quench the pin, it should be held in a vertical position, as opposed to a horizontal position.This prevents it from warping or developing a bend.
 
you can get oil hardening drill rod at fastenall store.. its usually in a rack with pin stock and iron rod. A taig lathe would work for firepin and they arent expensive.

When you heat the part to a red heat, use a magnet to tell when its hot enough to quench ( a magnet wont stick to part ) then quench it and test it with a file... the file should not bite but skate on it like glass. Becareful the part is extremely hard and brittle ! the part must now be reheated to lower temp to relieve some hardness and give it some toughness. If you know what kind of steel it is then you can easily look up the proper temperature to get your desired rockwell hardness, with mystery its guess work!

If your lucky a spark test and comparison with a known sample can give you a idea of what steel your dealing with.

If you have a pottery store near by... buy some kaowool, inswool and line a cofffee can with it... make a cofffe can forge, this is simple to do and youll easily be able to heat your part and heat treat it with a propane torch

my 2 cents
 
Waba said:
Ok, back to the extractor problem.
I understand, the extractor itself is also the "spring" that bends up a little to glide over the rim edge and secure it, correct? And if this bend were straightened, it would [ or should ] work as designed?


So, I need to 1st anneal it, straighten it, then re-heat it and quench in oil? Is a propane torch hot enough to do this? I have a small mapp bottle if not.

It is the tail end of the extractor that does all the spring work, but essentially you have the right idea.
Do not cold work to flatten. Use your propane torch and get the part to cherry red, use light taps to flatten it. You will see at this point if you have enough heat with your torch to do the hardening. As BCRider said, you need to do the whole part.
Trial fitting will show you where you are at. I would get a slight amount of preload into the spring, say, getting the pin hole to sit high by 1/64" or so.
Temper as soon as the piece is cold to the touch after the quench. The lead pot is best for this.

I am assuming that the steel used was simple hi carbon and that there are no stress cracks present. Don't go past cherry red colour in working it , you want to avoid grain growth.

If you lived next door to me we could do the whole job in 15 minutes.
Click to expand...



Waba,
Do I straighten it when it is still hot from annealing, or wait till it cools down?
Not sure what you mean by getting preload into spring......do you mean to put a slight convex curve into it, as in the opposite to what the bend it has now? ......but over the entire length of it, with the pin hole [ center fulcrum ] being the highest point in the convex curve?
 
Great tips guys thank you. Holding it vertical instead of horizontal when quenching.......I would not have considered that.

Please bear with me, I'm going to get'er done, just never have done any heat tempering before, let alone on such a small part. Once I have it straight in my mind, the steps that need to be done, I'll research the finer points of annealing, hardening and tempering on youtube and google and of course on here!

The gun was made in 1927.....so I don't know what kind of steel the bolt and associated parts are made from......the idea of taking a grinder to it to see the sparks freaks me out.....it's such a tiny part, so not going to do that. I'll assume that it is a ? medium carbon steel? Thoughts?
 
Spokerider said:
Waba,
Do I straighten it when it is still hot from annealing, or wait till it cools down?
Not sure what you mean by getting preload into spring......do you mean to put a slight convex curve into it, as in the opposite to what the bend it has now? ......but over the entire length of it, with the pin hole [ center fulcrum ] being the highest point in the convex curve?
Click to expand...
Sorry Spokerider, I type so painfully slowly that sometimes my brain gets ahead of my fingers. You have the right idea of preload, but the slight convex will be on the tail end, from just a tad ahead of the "wrong way" bend it presently has.There is too much mass in the "business" end to attempt any bending there. You don't want to bend too close to the hole, for fear of distortion or breakage.
An annealing step is not necessary. Just take the torch to it and flatten/bend it hot. Do not cold work it at all.
As for preload, I don't know how much you will need but I did suggest 1/64" or so. After flattening, place the extractor in position then sight through the hole. It should be misaligned slightly,with the hole in the extractor being slightly high compared to the bolt hole.
Quench from a uniform bright cherry red. The magnet test won't work on such a small piece, the colour I described is fine, quick into the quench. Then temper.
 
It takes some practice to be able to spark test a steel ! And youll need alot of known samples to compare it to ... 1020 -1095,w1, o1,d2,5160,etc.... your comparing the color of the spark, length, secondary burst, size, and flowery shape, color

But due to the age, id assume its just a plain carbon steel with spring temper or case hardened mild iron

yes.. forge it flat at a red temp
 
Yes forget spark tests, if a small file will cut in on the back side, where you don't see it, it is not harden steel,
if the shell end ,hook is bent over, than likely mild steel
 
Thank you all for chiming in. It helps.
I'll read up on hardening techniques and tempering techniques a little more before going at it. If I bugger it........I haven't lost much, it's a cheap little single shot.....
 
Random thought... How fast were you working the bolt when you tried to extract the fired round?. Did the case come out easily when you extracted it manually? Was just wondering if the extractor is supposed to be the way it is.
 
Not sure what to do about the extractor. I work in a wire EDM shop and made a bunch of firing pins for browning trombones (old trombones) out of heat-treated O-1.
That said... those in the know have been saying that they're discouraging people from asking for O-1 because the quality of O-1 these days has declined from "the old days" (probably 5 years ago).
They're encouraging those folks to use A-2 instead.
A lot of allan keys are made out of S2. If you look through Brownells at some of the parts listed (e.g., 1911 sears) you'll see them EDM cut out of S-7. These are tough tool steels used in the stamping of car parts. If you want to go even tougher (and more expensive) consider M4 or V4E..
 
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