MAUSER K98 SCOPE MOUNT

Question

I am building a sporterized Mauser K98 in 9.3 x 62. Why? Because I want an African (entry level) gun! It will not be used for hunting.

I want to use a low power scope on it and need to drill and tap the receiver for the bases.

1). What is the best scope mount setup for this application? Note: New target profile barrel with no fixed sights on CZECH K98 action from WWII.

2). What is the acceptable way to drill and tap the receiver with its hardened surface?

3). Heating the receiver even locally at the screw hole has me concerned about screwing up the heat treat of the rest of the receiver, especially in the lug area on the front ring. Is there a way to use Carbide tool like a carbide drill and a regular tap?

Answer

Well that is a tall order especially since much of what you want to know is purely up to you and your likes and dislikes. The “best” scope mount setup is what you like the best or can afford. Since the barrel won’t have sights you really don’t need a base/ring combo that will detach. I would still look at the Talley bases and rings; I use them regularly and really like them. I also like the Conetrol bases and rings and a similar set up to the Conetrol is the S&K bases and rings. What is great about both of these is that the rings are very streamlined and there is nothing to snag on anything. They are all steel which I like and both the front and rear ring hold the scope and take the recoil, unlike the Leupold and Redfield style where only the front ring holds the scope on the rifle. Also with the S&K and Conetrol rings both the front and rear are windage adjustable. If weight is a concern the new Talley aluminum light weight mount is great the bottom half of the ring is also the base and bolts right to the top of the reciever. These are strong and yet light weight. You can go with the Gunmakers bases from Leupold and make the bases fit your gun specifically, and in that case I would get the Leupold Dual Dovetail, so once again both the front and the rear rings take the recoil. Last but not least you can check out NECG… that is New England Custom Guns. They import a lot of high end stuff from Europe and among the things they have is the classic German claw mounts, GREAT mounts but a lot of work and they are NOT cheap.

As far as drilling and tapping I have never had a really difficult time drilling Mausers. If you are concerned break the surface with a carbide drill and then go back to the regular drill. You are correct about spot annealing although you only really need to be concerned with the one hole by the locking lug the other 3 holes won’t be a problem.

It sounds like you have a great action and a great project planned. Please keep us all appraised of your progress and if you have any questions feel free to ask. Also you may want to get the Mauser video’s that AGI offers if you don’t already have them. This really isn’t a shameless promotion there is a lot of information in all of them. If you decide to get them watch them all completely before you do any work on your gun.

I really like the 9.3×62 cartridge as well and let me know how it performs.

Reply:

I have heard horror stories (all second hand) about breaking drills and taps in Mauser receivers. Is a center drill hard enough to break the hardened surface or do I need a real carbide drill? But you say you don’t even do that….Just drill with regular bits????? and regular taps????

Thanks for the info.

Answer:

I use regular high speed drills and taps. If you have problems or think you will anneal the area on the rear bridge for the holes there. You can spot anneal the area of the front receiver for the front hole as well but don’t do it with the barrel in place unless you have done it before and are confident you won’t get things too hot. As far as the rear hole on the front receiver ring you can use a carbide drill or you can even take a Dremel tool and grind thru the surface case hardening with a small carbide burr just where you intend to drill and tap.

Answer:

Remember that the Mausers are just case hardened over mild steel. If you use a carbide center drill (as I do), stop as soon as you break through the surface and are drilling a full diameter hole. Go back to a high speed steel drill at this point or you will break your expensive carbide center drill. We recommend using carbon steel taps because when you break one off in a hole (and you will!), you can shatter the remnant in the hole with a center punch and pick the pieces out. With high speed steel, you will have to grind it out with a small Dremel (or Foredom) burr.