Spanish mauser m93 two piece firing pin build

[Webley No.5]

Intro (feel free to skip this first paragraph if you only came here for the build info).
So awhile ago I got an Oviedo m93 at an auction, this was pre COVID and in person so you could inspect the guns but they had removed the bolts from them all. So I buy this mauser get it home and the firing pin as no tip, I looked for quite awhile and couldn’t find one in Canada or one that would ship to Canada. So first thing I did was put a couple dabs of weld on the what was left of the top and then ground it to fit (making sure to ball the end). That actually worked for awhile until I dropped the pin on a concrete floor and the tip broke again. So it was time to make new.

First attempt
On the lathe with a center I cut the basic shape leaving the tip and the part in front of the gas shield (shoulder?, the widest part of the mauser pin) larger for strength while turning. I then ground a pieces of tool steel to cut the grooves where the cocking piece locks in. I the. Parted the pin off and mounted it in the mill to cut the flats in the pin. I then went back to the lathe and choked up on the pin to cut the area ahead of the gas shield. While attempting to cut the tip I bumped the in feed a bit too much and broke the tip off, right back to where I started. I didn’t want to start over after all the work of fitting the body of the pin. So, I decided to make a removable striker so that when I break more it’s less of a hassle. So I cut the pin flush at the gas shield and drilled and taped it for 10-24 with countersink to allow for a shoulder on the striker piece to help center it. This is where I learned the value of a good tap, broke the one I had in the pin slightly below flush. Fought with it for awhile before I started over.

Second attempt
Basically the same as before but I only made the pin up to its widest part, then drilled and taped it. As a side note, Morse cutting tools taps are my new favourite. With the body built and fitted to the bolt, I just hade to make a thread in striker which is pretty straight forward and a way simpler fix.

Two parts next to the broken pin

Assembled

So why did i build a two piece firing pin? As I said above it gives me the freedom to screw up the tips without swearing. 2. I’m not sure the best steel or heat treat for the striker so this makes experimenting easier. It makes machining the tip easier since I can choke up on the striker in the lather chuck where on a solid pin the widest part prevented this.

Two strikers, one is 4142 the other is O1 tool steel, right now my plan is to quench both and temper just the O1 and see how both do on firing.

Update
I quenched and spring tempered all the parts today

Also I test 4 shots on the 4125 steel pin (I called it 4140 but I was confused above), functioned well with no deformation of the pin so far.

 

[bearhunter]

You can easily fix the other unit with the broken off tip, simply by turning off the tip itself, drilling a hole and silversoldering in a pin of the proper diameter to fit the bolt face opening.

I've done that on several occaisions and haven't had one come back yet.

I use ordinary drill rod for the new tip.

From your photos, you do nice work and I like what you've done.

 

[fingers284]

I have used drill rod also , machines to size easily and torch heat treated then drew down the temper in a the wifes oven for 1hr at 400. Not sure if a trained metallurgist would do it that way but it works very well.

 

[Potashminer]

You can easily fix the other unit with the broken off tip, simply by turning off the tip itself, drilling a hole and silversoldering in a pin of the proper diameter to fit the bolt face opening.

I've done that on several occaisions and haven't had one come back yet.

I use ordinary drill rod for the new tip.

From your photos, you do nice work and I like what you've done.

I had an acquaintance bring over a Levermatic Marlin in 30 US Carbine - "to take a look at" - it would no longer fire. Just a hole in end of firing pin where the tip used to be. Just guessing the tip had disappeared, and a new pin was made and installed as firing pin tip - then it, too, "showed up missing". With good light down into the hole, I could see a "ball" of solder - tip had never been actually "soldered" in there - best guess of mine was that it was working for a while only because of the friction fit into that hole. I think that is a good idea to repair, when replacement parts not to be found, or too expensive, or simply not on hand - but perhaps need to do the job completely, not "part way".

 

[Webley No.5]

So I have heard of the soldering a rod in technique when I was looking up about firing pins for m93. I had a few reservations about doing it to this pin but I am interested in the experiences others have had. When I got this pin (before I welded it longer) it seemed rather hard and brittle. A file skated on it and the grain structure at the break was very large. I figured to face it off and drill it would require a thorough anneal and there maybe still be undissolved carbides inside that would dull/break drill bits. Do you guys just face and drill the pins or are you annealing first?
What grade/alloy of silver solder are you guys using?

 

[Potashminer]

I did not try to fix that Levermatic firing pin - was able to get the correct replacement from Numrich in USA. Had found a write-up in Internet about how to make firing pins from drill rod - the heat treating required, etc. Decided that was over my head, so went looking for a replacement part. I also have a P14 in 303 British that former user was firing until the previous fall - while cleaning it, I discovered about half of the "ball" shape at firing pin tip was gone - as you say - as if it was crystallized and chunks were breaking out of it. No mention of perforated primers from seller, but I also did not ask him about that - was able to find a correctly marked replacement for that one as well - did not try to repair it.

EDIT: upon reflection, you're going to have to pardon an "old guy's" mis-recollection. The Levermatic firing pin was replaced because the tip was broken off. It was a very beat up Winchester 92 in 44-40 that had the hole in the end of the firing pin - rifle had quit working while GrandPa was still using it in 1950's (?) - Grandson had inherited it and wondered if it could be fixed, or just okay to hang on his basement rec-room wall - he was not willing to spend 5 cents on it, so he took it back in same condition that he brought it to me - except much, much cleaner!!!

 

[bearhunter]

So I have heard of the soldering a rod in technique when I was looking up about firing pins for m93. I had a few reservations about doing it to this pin but I am interested in the experiences others have had. When I got this pin (before I welded it longer) it seemed rather hard and brittle. A file skated on it and the grain structure at the break was very large. I figured to face it off and drill it would require a thorough anneal and there maybe still be undissolved carbides inside that would dull/break drill bits. Do you guys just face and drill the pins or are you annealing first?
What grade/alloy of silver solder are you guys using?

Carbide and Supertanium drill bits do wonderful things

I've done both methods

I was in a pinch for time on one repair and didn't have any drill rod on hand. I drilled out the stem and inserted a hard roll pin. Melted the tip with a torch, shaped it with a small hammer to close the end and filed/polished it smooth. Worked just fine. I asked the fellow to bring back the rifle after his hunts were done for the season.

That was ten years ago, he keeps threatening to bring it back and he's shot a few thousand rounds out of that old M96 Swede.

Surplus firing pins are available for those rifles or they were.

If you don't have the tools, most don't, damnably expensive, you will have to soften the steel in the firing pin to drill it.

Stems from broken drill bits will also do the job.

 

[Webley No.5]

Yeah I don’t really keep anything around for carbide drills. I don’t think the old lathe is stiff enough, a small carbide drill wouldn’t last long. I built a very well insulated forge for the purpose of annealling scrap for stock, I find it easiest to machine dead soft steel and then quench and temper after, propane is cheaper then carbide haha

 

[bearhunter]

Yeah I don’t really keep anything around for carbide drills. I don’t think the old lathe is stiff enough, a small carbide drill wouldn’t last long. I built a very well insulated forge for the purpose of annealling scrap for stock, I find it easiest to machine dead soft steel and then quench and temper after, propane is cheaper then carbide haha

Supertanium is better than both carbide, which doesn't cut very smooth and HSS.

Your method works for you and I don't see anything wrong with what you've done in the pics. Why change what works?

 

[Webley No.5]

Sometimes it’s nice to try other methods, usually I figure out the best way to do a project after I’ve done it…. I may try your method on the broken pin and keep it as a spare. Do you have a specific alloy of silver solder to recommend seems there are a lot of options

 

[bearhunter]

Sometimes it’s nice to try other methods, usually I figure out the best way to do a project after I’ve done it…. I may try your method on the broken pin and keep it as a spare. Do you have a specific alloy of silver solder to recommend seems there are a lot of options

Nope. just ordinary silver solder. Ordinary soft 50/50 lead solder would work just as well and require much less heat

Even a good strong epoxy should work, as long as the pin is bottomed out.

Sweating the pin in place would also work well, friction fitting is extremely strong and durable.

There really isn't much pressure or force on the tip of the firing pin. The bolt face should take up all of it, after the initial strike has forced the cartridge case back against it. The firing pin spring will take up the initial shock.

 

[Dosing]

Awesome post. I ran into several lee enfields with the same work. Great to see some craftsmanship rather than just component replacement.