Mauser .223 bolt conversion help

[rodgervich]

I picked up a started project gun at the last show for $20. It's a Venezuelan large ring Mauser that has a really nice barrel chambered for .223 Rem ( I cast it with Cerrosafe). The reciever has been shortened but there was no bolt, it has a semi inletted stock from a nice looking walnut blank (block). I picked up an extra bolt and have read my Kuhnhausen book cover to cover several times. The receiver shows just the slightest bit of evidence that it was welded, the magazine and trigger guard matches length. So i need to shorten the bolt, heat sink and Heat Stop Paste are on the way and I plan to silver solder the bolt back together but gas and arc welding are available in my garage also. My main question is the bolt face, what should I do for the small head on a .223 case? The extractor looks like it will hold in the groove but how to shrink the bolt face to support the case head? I don't like the idea of welding and opening it up for fear of annealing the locking lugs. A friend suggested boring the face and pressing in a bushing, drill rod material. Has anyone done this before? If so what did you do for the bolt face? Can I just leave it big and have the case head unsupported? Any ideas from anyone would be a huge help! Thanks in advance!

[gunnut69]

I personally have not done this before but have seen it done several ways..  The bolt face could be left as is.  The extractor will pull the case from the chamber but will not retain it, so the ejector will not function..  The part of the case extending into the bolt is solid for the most part and will cause no problems.  In the case of the bushing, a hole is drilled thru the bolt dave and a bushing is turned to a very tight press fit.  It looked to me as if the bolt face had a bit of a cleanup cut made to provide square edges.  A bushing was turned and the firing pin hole drilled and the bolt face 'created' in the diamter needed.  The extractor was 'extended' by welding and this is what had failed.  I repaired the extractor and the rifle (a 222 mag) worked just fine.  I would be very cautious about removing metal from the bolt face although drilling through the firing pin hole works fine.  Both of these examples were single shots and getting a magazine to feed the tiny rounds would be the largest hurdle to overcome.

[rodgervich]

How about silver soldering a support ring in the bolt face? It's lower temperature than actual welding, but I'm not sure how much lower. Would you think that would anneal the locking lugs? Think Acraglas would hold a ring in place or would the repeated shock work it loose after a few rounds? That would be the easiest and most reversible/repairable attempt. Spare bolts are not that expensive but shortening them is going to be a bit of work, so I would prefer not to destroy too many (any!). What do you think of the silver solder idea?

[gunnut69]

I believe silver solder would be too hot..  It would anneal the lugs..  as would any type welding I can think of.  I don't believe the bolt face sleeve needs to be held in place other than by mechanical fit.  I would drill thru the firing pin hole to a diameter slightly smaller than a small rifle primer.  Turn a blank to fit the current bolt face (clean and square it up with a lathe cut first).  Leave a stem on the back of the turn blank to a press fit in the hole bored in the bolt face.  The stem should protrude only slightly thru the bolt face.  The blank face would then be supported and a long punch would be used to slightly swedge the stem from inside the bolt.  The bolt face would then be cut to the correct diameter for the 223 and the firing pin hole drilled.  Shortening the bolt is accomplished by centering between centers in the lathe (pull with a dog) and cutting the extractor collar recess back the amount to be removed from the bolt and an extra 1/2 inch.  The cut is then made at the rear of the just cut relief.  The rear section of the bolt is then, supported in a steady rest, bored to accept the diameter of the extractor collar to a depth equal to 1/2 minus the cutoff saw kerf.  The extractor collar cutout must be the same after the bolt is rejoined.  Special care must be taken to insure the relationship of the bolt handle-cocking cam and the locking lugs remains the same as before.  With the lugs properly covered in a heat sink, the halves of the bolt are rejoined using a low temp silver solder.  This is not an inexpensive undertaking in time so one ,ust really consider the value.   If the value is in the doing, then by all means have at it..  The firing pin's shortening may be even more difficult.  It will be accomplished along the lines of the bolt but the material is considerably harder.  It may be neccessary to anneal the center section before proceding.  I may well be simpler to machine a new pin out of drill rod with the measurement relecting the needed change.  Also just as an asside before undertaking any further work I would check the harness of the locking lugs seats in the receiver.  They should be hard enough for a file to 'skate' over them.  If not they may have been damaged by the welding process that rejoined the receiver halves.  While the 223 will not stress the lugs as much as other high intensity rounds, soft lugs would definitely set back, ruining an awful lot of time and effort..  good luck, hope I have helped some,,the gunnut69

[Double D]

I have done a couple of these using the technique put forth by the late Frank Dehaas. This method was also given me by the late Harvey Donaldson. Gee, a lot of dead guys old technigues gettin relearned here.

Solder in a ring, the inside diameter of which is just a hair larger than the head of your small case, a thickeness of the raised portion around the outside of the face of the bolt  After the solder cools cut away the lower side of the ring and polish with a stone. Recut the slot for the ejector.  No Engineers or CNC machines needed at all.

The type of solder to use is that Force 44 solder low temp solder sold by Brownells.  All you need is one of those hardware store propane torches.

I use that same solder for joining shortened bolts also.

[rodgervich]

:-)  Thanks to both of you for the information, it will be a huge help! This will be my most challenging project yet and I'm sure it will be the most rewarding (so far).
It's important to learn from the past and this is a great place to do it. I'll put up some results when I get the project to some interesting points or completed.

[445supermag]

Charles dayle has a shorten action for 223. Check if the bolt lenth is the same. The extractor will be made for the 223. Also browning had a mauser action in 223. I got 2 bolts from gun parts for 223. They also had mag boxes for the 223. If you get one of these you can shorten it to the lenth you need.There was a soft cover book on gun smithing bolt actions that had a good articule on shorting the mauser action and bolt with pic. darn if i can remember the name.