Was wondering what was done about the tapered hole in the bolt head.
The cocking piece would soon have started to loosen up slamming into the back of the bolt, hence the peening in an attempt to tighten it up probably.
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I was handed one where the striker stuck fast in the bolthead when the trigger was pulled, making it difficult to cock. It was a de-act, so not safety-critical.
Eventually decided someone had put a No.4 striker in it.
Made a brass collar to go on top of the striker collar and keep it further back from the bolthead.
LE / SMLE strikers have a different thread from No4 strikers: 1/4 x 30 TPI (Enfield Special) vs 26 TPI (1/4" BSF) on the No4.
LE strikers are also longer because of the greater length of the "tail" on the bolt body and the cocking piece that fits over it. As for the bashing on the tail of that striker; maybe the lock-crew was missing at some stage and bubba "peened" the thread.
The striker is supposed to be an extremely "close" fit in the cocking piece. This is to be achieved, not by any "locking" effect of the thread, but by the striker body diameter and parallelism being a "perfect" fit into the matching, similarly precisely-made hole in the body of the cocking piece. "Wobbly' cocking pieces are a major threat to the safety of the trigger/ sear operation.
My initial thought was to save the bolt head by doing something like this but the enlarged striker hole worries me too much...
Even though i don't plan to shoot it, being DP, i still like for it to be in as much good order than i can make it.
I have the parts so might as well use them. If i need them for something else i'll know where they are.
It still a work in progress so i might decide on another direction before i'm done.
---------- Post added at 03:26 PM ---------- Previous post was at 03:21 PM ----------
This is the most unsafe (at least that's how i felt) rifle repair i've come across so far.
I've seen deep pits but these were not cause by someone.
The person that did this probably fired dozens if not hundreds of rounds and never had problems, but the trouble who knows when it would have failed.
Most of the NZ Carbines were stamped DP & the firing pins tip were snipped off (mine still remains in that form) a lot have been "reactivated" over the years
I have two of them, one that was sporterized and the other that wasn't and both have DP markings.
Now that you mention it, i took a closer look at the full length stock one and the striker tip does protrudes but as a suspicious sharp edges (squarish) were it should be rounded off.
I'll have to check on that but my guess is that striker tip was also rebuild.
I'm in the final stage of finishing the stock on the sportrized one and was also checking the new bolt head, i noticed it would have to be fitted to the old body since the rotation is not enough. (sometimes you get lucky and they fit right off the bat)
Funny you mention you left your's in that ''snipped'' form...
I was thinking about mine and since i wasn't planing on firing it because it's a DP and that fitting a new bolt head would be pointless.
I would simply chop the ''fix'' off the old striker, fix the back end as best i can and reinstall both the old head and striker in the rifle.
I have no real reason to have it fully functional and working on matting the parts is kind of pointless (except to satisfy my OCD)
The bolt head is from a fully working bolt assembly and i would hate to risk not having it fit properly in case i need it for the future.
So i've finished restoring my second NZ Carbine (DP) and sure enough the firing pin looks funky.
Although the work on this one appears to be better, it lacks ''refinement''
Looks to me, he or they, lengthened a SMLE striker by cutting it and adding a length of pin to it.
What i am wondering, and maybe those of you that know about brazing can tell me is why was the cuts made like V notches... does it give the brazing more strength ?
Still not planning on firing that one neither but i am intrigued by the technique used (i know next to nothing about brazing or welding).
Attachment 111284Attachment 111285Attachment 111286
When we welded something like that firing pin body we sharpened it like a pencil in the lathe. Then you build it up. You can't weld two ends together without filling it. Cutting the groove gives you edges to weld to. Then you carefully take it down. I had to do a '73 Winchester firing pin once...HAD to as there were no replacements.
The fundamental difference between welding and brazing is that welding is achieved by melting and fuzing the original metal forming the joint, optionally adding material of the same type. Brazing and similar processes such as silver soldering or hard soldering uses a different metal to achieve the joint.
In brazing, the jointing material invariably has a lower melting point to the base metal, however the jointing action is achieved by the filler metal alloying with the surface of the base metal. Ideally the thickness of the layer of jointing metal should be as thin as possible so that the majority of the joint is made from alloyed material, which is usually stronger than the filler. Brazing alloys are usually made to have the lowest melting point achievable (eutectic alloys) which means that they go straight from solid to liquid with no "pasty" stage. This means that they are able to flow up narrow spaces by capillary action. As a result, the best brazed joints are made by cleaning up the jointing surfaces, but leaving only a small gap between them. When the joint is heated up and the brazing material added (after fluxing to chemically clean the surfaces!) the metal flows almost instantly up the joint giving a very strong bond.
Welding is a fundamentally different process. In welding, the base material has to be brought up to, or very close to, its melting point. In the old days, fire welding was achieved with alloys such as wrought iron by bringing the parts up to a "pasty" state where there was a mixture of solid and liquid material, and then hammering the parts together to achieve fusion. This was the process by which Damascus barrels were produced, but could only be done with certain alloys which had a "pasty" state as they melted. Welding pure metal or Euctectic alloy was only achievable when gas and electric methods of bringing steel up to melting point were developed. Welding is achieved by creating a puddle of liquid metal between the elements being welded. As the base material is being melted, you cannot achieve the fine gaps needed to create capillary joints. In a weld, the depth of the weld is limited to the depth of the weld pool, which is invariably less than the thickness of the material you are welding unless it is very thin (which causes other issues!). It is difficult in welding to fill gaps as the surface tension of the materials in the weld pool is quite high.
Welded joints are therefore much more of a surface effect than braised joints, and if a through weld is required, space has to be created to take the weld material which is added to fill the void. In practice a bevel is ground off the edges of the elements to be joined and a bead of weld run along the groove thus created. This is the reason for the V section in the welds illustrated above. One of the main criteria in weld design is the required weld penetration depth, and shallow welds are one of the primary causes of weld failure.
The choice of whether to braze or weld is not, as popularly considered, that of absolute strength, but more the nature of the join. A good brazed joint can be as strong as a weld if properly designed and carried out!
Someone once told me that the way of understanding welds and braised joints is to think about braising as using glue, whereas welding was more like using duct tape...!