Home grown 458

[tek4260]

I managed to build a 458 Win Mag at home out of an old VZ24 that I got from a friend. I'll post some pics of the build along the way when I get a few minutes. Here is a quick shot of the finished product.

[tek4260]

The Genesis of this rifle is a failed project. It was to become a 500 Jeffrey, but alas it didn't work out. I met up with a friend of mine who owned the rifle. During the visit, I checked the rifle out and found that the replacement bolt wouldn't quite work as it was received back from the gunsmith. There was quite a bit of rust under the extractor and around the rim of the bolt face preventing it from feeding from the magazine or allowing the bolt to fully close once a round was worked under the extractor. The safety didn't function either. The differences in the sear location of the donor rifle and this one had the cocking piece a bit too far forward to allow the safety lever slip in front of it. All in all a rifle that needed some work to even get back into firing condition. I thought most gunsmiths test fired rifles, especially after swapping the bolt since they had already modified the original one. After a good bit of cleaning and a wire brush on the dremel, I had it where it would feed and the bolt would close.



After a bit of horse trading, it came home with me


I should have shot it some, but alas, I already had plans for it....

[tek4260]

I'll start the thread and the picures of the build here. I started with stripping the rifle. Pretty straight forward and simple. I didn't have an action wrench, so I whipped one up outta scrap. Hey it beats spending over $50 on one. I thought about calling it my GOODWRENCH, but it only looks OK, so another name will have to be scratched along the handle.

Here is where I stand now.




And a few pictures of the wrench in case someone wants to make one. Pretty easy considering the Mauser has a flat bottom and internal lug. I simply took flat bar, 3/8" thick and 2" wide and cut a notch for the lug. Then I welded on a 4' handle of flat bar, with it on the opposite side of the notch, to contain and strengthen the plate. The top is the same flat bar with a section of round that matches the top of the receiver. I need to weld the round to the flat to make it a bit easier to set up on the rifle. Once welded, it won't take 3 hands to install it on the rifle. In the picture the half round is sitting upside down in the wrench from how it is when installed on the rifle.





Oh yea, the Loctite the gunsmith applied when he installed the original barrel was no match for the wrench...

[tek4260]

Then the brown Santa delivered my 458 Win Mag barrel. One of the short chambered jobs from Midway for $90-ish.




And screwed into the action for opening up the stock







Using these complex tools I was able to open up the channel for a full float. zgrin



The leftover



One little wide spot where the rear sight sleeve was



And the red line where it is about to be cut

[tek4260]

another piece of the puzzle for $25 from ebay

[tek4260]

Since I was wanting to do this project myself, at home, and with common tools, farming the bolt face opening was out. Midway has a bolt face truing tool for magnum bolt faces and a guide that threads into the front of the receiver. With it, you can insert the tool into the guide, close the bolt and turn it with a drill to cut the face of the bolt. Problem was that it was out of stock. While I was waiting for them to get more in stock I found a bolt already opened up on Ebay. I hated to use another one, but they were steadily pushing the date expected in stock back. But, on a brighter note, the bolt cost less than the tool.....







And the amount I'll have to deepen the chamber

[tek4260]

Rear peep mounted. I leveled the bottom of the receiver then the top if the sight, and drilled and tapped the receiver. Now to inlet the stock for the sight and the lower bolt handle.

[tek4260]

Did I mention I suck at wood work!

[tek4260]

Ready to drill and tap front

And the particulars on that sight drilling fixture:

Well here is the beginning



The way I make a square mark and use it as a saw guide to keep it straight




Then the triangle file




Deep enough to drill now



and drilled perpendicular with the proper size bit for drilling the sight holes. At 3/8" thick it is plenty thick enough to act as a guide for the drill bit as well.



Complex array of goodtools for an amatuer to get the job done



So now I can bolt it on the barrel, level the action and then this, and will get a centered sight.


I'll deepen the notch just a bit more, but as it is, it is ready to use.

[tek4260]

About this time my bullets came in for the rifle





Loaded a few test rounds. 325gr FTX over 80gr of H4895. Next to the original 8x57

Here is an image of the bullets with the rubbery tip pulled from one to give an idea of how thin the jacket is on these. Should open on deer.

[tek4260]

The original test of my opening of the action rails. Doesn't take much metal removal at all to make it feed. Just have to look at the places it binds as you close the bolt and carefully open the rails. At this point the chamber wasn't reamed.

[tek4260]

I used www.reamerrentals.com for my reamer. Fast shipping and good prices in my book. I had to make another goodtool since I didn't have a reamer extension. I simply took a 10" 3/8's extension, filed a flat on the outside of the female end so I could drill and tap it. I tapped it to 6x48 so I could use a simple plug screw from my parts box to hold the reamer in place. It needs to be captured so you can pull the reamer out while still turning it, otherwise it will leave gouges in the chamber.




Here is a pic of it with the reamer mounted and ready to cut




Notice the tape in the above pic. I wrapped the extension and made a mark to correspond with a piece on the receiver to give me an idea of how much I was cutting every time I made a revolution.




And here is what the reamer cuts. The chips are so fine that they look more like mud in the reamer mixed with the cutting oil.

[tek4260]

Feeds much better in the stock

[tek4260]

And the first round fired from the rifle at 25 yards is the lower hole. I swapped to a shorter front sight as I like my rear sights as low as possible along the receiver, and got the hole above the spot.

[tek4260]

I originally chambered the rifle where I could "feel" the case as the bolt fully closed, without the extractor in place. Since it was a rental reamer and I had to return it in a few days, I decided to cut the chamber a bit deeper. I slowly deepened the chamber just to the point it would close without feeling the case. The reason being is this is a belted round and I was afraid that if I left it closing with feel on this lot of brass, the next might have a slightly taller belt and I'd be renting or buying a reamer again. If it were an unbelted case, I could simply bump the shoulder back if I ever ran into some that were a taste long. I know everyone wants tight chambers, but in this case I felt it would be best if it had just enough room for differences in brass. Also, the extractor holds the round tight against the bolt face for firing even if the chamber is too deep. In this rifle it is not too deep, probably closer to factory specs.