Mauser K98 Help

[meyersa88]

So I bought a mauser a while back that came tapped for a side rail mount. Long story short, I have the scope and mount and put it on and the holes are WAYYYY off.... So I feel extremely stupid for having not inquired further about the drilling and tapping so I'm curious what if anything I can do to fix this issue.

Edit: I'll get pics up later tonight. The scope is pointing up and to the right from the bore axis.

Edit #2:
http://i264.photobucket.com/albums/ii196/redalert2785/IMAG0513.jpg
http://i264.photobucket.com/albums/ii196/redalert2785/IMAG0512.jpg
http://i264.photobucket.com/albums/ii196/redalert2785/IMAG0511.jpg
http://i264.photobucket.com/albums/ii196/redalert2785/IMAG0516.jpg

 

[sandwarrior]

Re: Mauser K98 Help

Put the side mount in a break and 'tweak' it until it points in the right direction. Clamp a 1" barstock in the scope rings so as not to offset them.

Short of that, take it to your gunsmith, that you trust, and have him drill and tap it for top mounts, for a picatinny rail. EGW and Farrell both make one piece picatinny rails to fit Mauser rifles. Note: If you go with a Weaver bases, you can use the same rings as Picatinny, but the fore/aft spacing is off.

 

[Veer_G]

Re: Mauser K98 Help

It might have come set up for something like this:

http://www.surplusrifle.com/reviews2006/newspinonthings/index.asp

 

[meyersa88]

Re: Mauser K98 Help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Veer_G</div><div class="ubbcode-body">It might have come set up for something like this:

http://www.surplusrifle.com/reviews2006/newspinonthings/index.asp </div></div>

I know for sure that that isn't the scope the rifle was drilled for because everything fits, but the scope and bore axis's are off.

 

[Veer_G]

Re: Mauser K98 Help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: meyersa88</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Veer_G</div><div class="ubbcode-body">It might have come set up for something like this:

http://www.surplusrifle.com/reviews2006/newspinonthings/index.asp </div></div>

I know for sure that that isn't the scope the rifle was drilled for because everything fits, but the scope and bore axis's are off. </div></div>

Ah ...

 

[meyersa88]

Re: Mauser K98 Help

Updated my original post with some pictures. If anyone wants/needs other pictures, please let me know and I'll take them as soon as possible.

 

[Alaskaguide]

Re: Mauser K98 Help

I have a 98 with a lilja barrel in a A-5 stock. The action was drilled for a scope mount that was not standard.

I ordered a Farrell one pice 20 moa rail for a 98 action. Had to order it with no holes drilled then had a the holes driled to match the holes on my action. That 98 now shoots as good as any rifle that I have ever owned.

 

[Frank Green]

Re: Mauser K98 Help

It only has 3 screw holes and no holes for locating pins. So my first guess is this had a short side rail mount on it. The mount and scope you have on it is a long side rail mount.

Later short side rail sniper mounts has two locating pins as well.

What year of manufacture and maker code is on your receiver? This might help to know.

Go down a few threads. My thread is K98 SSR build. Take a look at mine. It's a repo mount.

Later, Frank
Bartlein Barrels

 

[meyersa88]

Re: Mauser K98 Help

My receiver is marked dot 1944. I don't believe that the previous owner had mounted anything on the rifle.

Edit: My mount does have 2 holes for locating pins, however they are not present on my receiver. I do believe I still have them with the hardware that came with my mount though.

 

[BasraBoy]

Re: Mauser K98 Help

Re: Short Side Rail mount.

There were three different types over the course of it's lifecycle;

The first (Type 1)had three single screws - arranged in an upturned chevron pattern, highest in the middle - and was notorious for coming loose very easily.

This was quickly upgraded to...you guessed it...to the Type 2 (so logical these Germans

)

This had additional locking screws above the three main screws.

This also proved pretty unreliable.

So...no prizes...along came Type 3.

Same three main screws with their associated locking screws but the further addition of two tapered pins.

Sad to say, this still didn't do the trick so enter the Long Side Rail mount (this is the one you have judging from your pics)...this retained the same fixings as the SSR but, the main difference is NOT the mount itself (although longer and with a different locking lever mechanism) there were also changes to the receiver on the 98k.

The receiver of the 98k was thickened from late 1943 and faced off to provide a better, more stable metal-to-metal fixing. The thicker receiver scoped rifles that are known to exist seem to come from Sauer(ce43 coded) and Gustoloff (bcd43 coded)factories.

With your "out of true" holes...I had a similar issue....my SSR was around 20thou out of true....but as there was not enough internal adjustment on the Zielvier to compensate, I was told pretty much the only way to resolve this properly is to either:

a) weld up the holes, put the rifle on an engineering bed, clock it, align the scope to the bore and then reface/redrill the receiver

or - if the mounts legs are the same as the SSR (held in by a dovetail joint and screws) and it is just the vertical/elevation alignment that is out, to

b) shim/grind the posts of the scope mount as required to correct the problem.

The good news is it should be fixable

 

[Frank Green]

Re: Mauser K98 Help

I thought about this after I posted and was going to give the same advice that BasraBoy. I'll also add that you could weld up the holes in the mount. Take careful measurements off the receiver holes and machine new holes in the mount. Welding up the holes in the receiver and drilling and tapping although not impossible but with out proper tooling might prove challenging with the tap hitting any weld area etc...

Also most of the mounts back in WW2 era where commercial made. I doubt there was any standard for location of the screw holes.

I will also add this. With doing my SSR build. The mounts that are out there I believe are all Chinese made?! Not sure but who ever is making them where did they get they're dimensions from. I will also say the quality is not to what the German/Swede made. My Swede M41B side mount is night and day different in fit and quality. On my repro mount I had to remachine the bottom of the rear scope rings notches for the windage clamping screws. The notches where so poorly machined the screws didn't even hold it tight. Had about .010-.015" play in it. The depth of the notches was like crap and they where not even machined to the same width! I'll post pictures later of the scope ring bottom. I did take a couple.

If your mount is a repro your screw hole spacing being off could be part of the problem as well.

It's also possible that some gunsmith after the war put some sort of side mount on it but who knows as to what and it's not even a wartime made gun.

A DOT44 receiver? If you would've said a 42 or earlier made receiver than I would say for sure it's a SSR type mount but the Germans did use SSR mounts thru out the whole war. They we're pressed for anything they could lay they're hands on.

Later, Frank

 

[meyersa88]

Re: Mauser K98 Help

Well, after further examination of my mount and my receiver. It appears as if the radius of the mount that makes contact with the receiver is a much smaller diameter than the radius of the receiver. So, all in all, I don't have the right mount at all. Is there some sort of spacer that I could fabricate that could match the contour of a thick walled receiver? I know at this point that the holes will have to be filled, but the only access around here I have to a welder is through a friend of mine and well... the welder is at our university so that idea is out.

 

[Frank Green]

Re: Mauser K98 Help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: meyersa88</div><div class="ubbcode-body">Well, after further examination of my mount and my receiver. It appears as if the radius of the mount that makes contact with the receiver is a much smaller diameter than the radius of the receiver. So, all in all, I don't have the right mount at all. Is there some sort of spacer that I could fabricate that could match the contour of a thick walled receiver? I know at this point that the holes will have to be filled, but the only access around here I have to a welder is through a friend of mine and well... the welder is at our university so that idea is out. </div></div>

From what I understand is that some mounts the area that contacts the receiver might need to be shaved/fitted so it mounts on the receiver properly. This also pertains to zeroing the mount for elevation/windage as well also. You want it as close as you can to being zero before drilling and tapping and mounting it. See my next post.

Later, Frank

 

[Frank Green]

Re: Mauser K98 Help

Take a look at the attached pictures. The first two here are views of the bottom of the rear scope ring. The one ring with a s/n on it is an original SSR mount ring off of my Swede M41b. Notice how compared to the repo mounts rear ring the nothes in the bottom are not machined properly. I had to remachine these notches and made them to the same dimenions to the M41b scope ring. Also the circular recess in the scope mount base where the rear scope ring goes and the screws tighten up the ring and adjust it for windage. The recess wasn't deep enough as well. The screws wouldn't tighten up or adjust for windage. I had to deepen this recess approx. another .040" more on each side.

The next picture is looking down on top of the original mount on the M41b. See how the dovetail cut out has a curved shaped to it. My repo mount didn't have that. With the repo mount and rings make sure the windage is as close as you can to zero because with the straight machined dovetail they did you will have a limited amount of windage adjustment. Probably on Friday I'm going to check to see how much I have.

The last picture that I show is the bottom of the top of the rail mount that mates with the rail base. Notice the shiney area at a 45 degree angle on the one edge. This is the side of the mount that if I'm taking it off the rails receiver base to remove the scope mine was binding/hitting the receiver as I took it off. So I milled the 45 degre clearance cut on mine so it doesn't hit. I have a .005" clearance on mine.

These are the problems that I ran into in doing mine.

Later, Frank
Bartlein Barrels

 

[Frank Green]

Re: Mauser K98 Help

Here is a side view of my mount installed.

Later, Frank

 

[meyersa88]

Re: Mauser K98 Help

Thank you so much for the help. I was playing around with the windage and I have enough on there to have the windage matched to the bore at least, now I just need to match the elevation which is going to be the difficult part.

 

[Frank Green]

Re: Mauser K98 Help

Get some shim stock. You can put it under the flat side of the mount to get the elevation correct. Then mark your holes before drilling and tapping.

Later, Frank

 

[meyersa88]

Re: Mauser K98 Help

What is the best way to modify the mount to mate better with the receiver using only hand tools and a bench vise?

 

[wilecoyote]

Re: Mauser K98 Help

What is the best way to modify the mount to mate better with the receiver using only hand tools and a bench vise? [/quotmeasure the receiver's diameter,and find a tube/round stock section w. the same radius_ properly heating and massaging the mount against this bar,you can try to bend it to the desired form __ good luck

 

[meyersa88]

Re: Mauser K98 Help

I also have another mauser that is a S/147/G marked receiver but the barrel is pitted and can only hold a nice 36 MOA group at 100 yards. I'm considering doing a bit of part swapping between the two since neither has matching SN's so I'm not really doing anything that hasn't already been done. I was also looking into getting a Lothar Walther barrel to replace the pitted one and was wondering if anyone has any opinions on that.

As far as I can tell so far, the general consensus is to weld the holes back up, re-drill/tap, modify the mount to match the radius of the receiver and I should be good to go. Is there a less "destructive" way to fill the holes back in such as JB weld perhaps. I'm worried about the welder ruining the heat treatment on the receiver. Just throwing ideas out there before this rifle becomes anymore messed up than it is already.

Thanks again guys.

 

[Mike Hull]

Re: Mauser K98 Help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: meyersa88</div><div class="ubbcode-body">I also have another mauser that is a S/147/G marked receiver but the barrel is pitted and can only hold a nice 36 MOA group at 100 yards. I'm considering doing a bit of part swapping between the two since neither has matching SN's so I'm not really doing anything that hasn't already been done. I was also looking into getting a Lothar Walther barrel to replace the pitted one and was wondering if anyone has any opinions on that.

........
Thanks again guys.</div></div>

Nothing wrong with the L/W barrel as they're match quality, the problem is finding someone to install it. You'd be surprised at how many "gunsmiths" can't work on anything but M700 Remingtons.

 

[meyersa88]

Re: Mauser K98 Help

With the proper tools, how hard would it be to replace the barrel myself?

 

[sandwarrior]

Re: Mauser K98 Help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: meyersa88</div><div class="ubbcode-body">With the proper tools, how hard would it be to replace the barrel myself?</div></div>

First, you will need a lathe. Then, you will need a clamping device to put your action into the lathe, so you can true it (there are a few types, not just one). As well, you will need as your barrel. You will need a reamer, unless the barrel comes 'chambered long'. In which case you'll just need to chuck it up and cut it to length at the tenon and shoulder. Cut those to their proper lengths and then screw the barrel into your trued action.

I'd recommend a gunsmith. Or, find a local machine shop where someone you know can walk you through on a Saturday or something.

FWIW, you been getting a lot of good information from a barrel maker on this thread, Frank Green. Who is with Bartlein Barrels. You might give him a call at least since he's taken the time to help you.

 

[Frank Green]

Re: Mauser K98 Help

Meyersa88, I returned your PM.

Unless there is something really wrong with the action I would save your money on the truing of the action. Why?

There is so much bolt clearance on the bolt body to receiver bolt area you could be making it worse by truing the action unless your going to sleeve the bolt so it fits the receiver with less slop/clearance.

Also there is no point in truing the receiver face on a 98 type mauser action unless the barrels shoulder is going to butt up against the receiver face. The way Mausers are suppose to have the barrels installed (at least military type) the breech face of the barrel tightens up against the shoulder inside the receiver behind the threads. The barrel isn't suppose to tighten up against the receiver face on the outside. Unless you can get to that face (on the inside) and true that up I feel your beating your head against the wall. Also if your putting it back into a military type stock and the barrel is properly clearanced on the bands and pressure points etc...what are you really gaining other than peace of mind.

Just random thoughts.

Later, Frank

 

[meyersa88]

Re: Mauser K98 Help

All I'm really looking to do by putting a barrel in there is get something that can shoot fairly accurately but maintains it's original look as closely as possible. Unfortunately, the receiver has been drilled and tapped for a 2 piece modern base so in all likely-hood, I'll be using a modern scope but other than that I would like it to look as close to an original mauser as possible.

 

[Frank Green]

Re: Mauser K98 Help

My K98 pictured above is as of right now shooting around 3/4" to 1" groups at 100 yards. Other than the scope mount and Timney trigger and my handloads nothing has been done to bedding/barrel clearance etc....and with that being said for what the gun is I don't think I'm going to get it a ton better. I didn't true the action etc....just lapped the lugs.

Later, Frank

 

[meyersa88]

Re: Mauser K98 Help

I think I would be happy with 2-3" groups with my rifle in it's current configuration.

 

[Frank Green]

Re: Mauser K98 Help

The other thing that is probably holding me back is the scope. That German post reticle I have a hard time holding my elevation. Windage I can hold pretty good. The cross hairs don't give me a consistent sight pattern to hold. I think I just have to find the right bullseye/target to shoot at.

Later, Frank

 

[Wonko_The_Sane]

Re: Mauser K98 Help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Frank Green</div><div class="ubbcode-body">The other thing that is probably holding me back is the scope. That German post reticle I have a hard time holding my elevation. Windage I can hold pretty good. The cross hairs don't give me a consistent sight pattern to hold. I think I just have to find the right bullseye/target to shoot at.

Later, Frank </div></div>

Have you tried just a simple 1'' black dot on a white sheet?

I know I have pretty good luck with that when using the chevron reticule on the NDM-86.

 

[Frank Green]

Re: Mauser K98 Help

No I haven't yet. I'll give it a try!

Later, Frank

 

[meyersa88]

I figured I would revive my old thread instead of start a new one so here it goes. I have since "fixed" the mount so the rifle is now bore-sighted at least. My issue now is that I only have 2 screws holding my mount to my receiver so I'm worried that when I start shooting that the mount will get shaken loose as is apparently a common issue from one of the above posts. I do have the ability to modify the third screw hole on the mount so that it is also being used, but I still am not making use of he two locating pins and am unable to use 2 of the locking screws on two of the screws because of the modification to the mount. I hope to shoot it soon to see if it will hold and to see what type of groups my rifle is capable of. Obviously the latter of those will be impossible if my mount doesn't hold but one can only hope.

I know before I had inquired as to the difficulty of barrel swapping on a K98, but I forgot to mention that I would be buying a factory finished military contour barrel. Not sure if this will change peoples opinions as to the degree of difficulty of a swap or if it will just result in the same conclusion that was come to above. I am by no means mechanically disinclined however I do lack access to a lathe or mill, which is part of the reason this process has taken me so long and was done so crudely.

Any help again will be very appreciated. Thanks in advance everyone.

 

[BasraBoy]

Swapping the barrel may sound easy but if the barrel has never been removed, it may be a problem 70 years on. I know the barrel on my K98 is going nowhere now.....

Before you start drilling or anything more drastic I'd loctite the mount and screws using red loctite.

OK, you'd need heat to remove it but my smith recommends this as a solution now instead of the more destructive (and archaic) staking.

On my GAP build M40A1 red loctite was used under the mount to secure it to the receiver. My smth did likewise on the bases on my 1903A1 build. Nothign has come loose so far......

 

[Frank Green]

Most of the time I just use blue loctite. Easier to work with to get the screws out vs. the red locitite but I agree using the loctite makes more sense vs. staking etc.....

Getting the barrel off of a K98 is like working on any other rifle. No big deal really. I did have my DUV 41 rifle when I was taking the barrel off the barrel cracked loose but after that it wouldn't turn. As soon as it popped and stopped turning I knew what happen. One of the threads started to tear. First time it's ever happened on Mauser action to me. So I stopped trying to remove the barrel with the action wrench. I cut the barrel off leaving about 4" in front of the receiver still. We set the action up in the milling machine. Indicated it in for center of the bore etc...then slowly milled out the barrel going towards the inside diameter of the receiver threads. Just about when we saw the very tip of the threads we stopped. The rest came out like butter. Sure enough 1/2 of a thread started to tear. Used a tap to chase the threads and all was fine. Then installed the new barrel.

Later, Frank
Bartlein Barrels

 

[Dave Roberts]

So I bought a mauser a while back that came tapped for a side rail mount. Long story short, I have the scope and mount and put it on and the holes are WAYYYY off.... So I feel extremely stupid for having not inquired further about the drilling and tapping so I'm curious what if anything I can do to fix this issue.

Edit: I'll get pics up later tonight. The scope is pointing up and to the right from the bore axis.

Edit #2:
http://i264.photobucket.com/albums/ii196/redalert2785/IMAG0513.jpg
http://i264.photobucket.com/albums/ii196/redalert2785/IMAG0512.jpg
http://i264.photobucket.com/albums/ii196/redalert2785/IMAG0511.jpg
http://i264.photobucket.com/albums/ii196/redalert2785/IMAG0516.jpg

Looking at Your Rifle and I can tell You the Base that Your using is a Long Side Rail Base and so is Your Mount . You need a Short Side Rail Base .

Whats the Code on top of Your Rifles Receiver and the Years also ????