Project: Medium Bore, Part I

The Metamorphosis of a K98 Mauser Action from Ugly Duckling to Soaring Eagle

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‘Ole Reliable, a Diamond in the Rough

Part I. The Concept

In a world where everything seems to follow suit; the sameness of things can become, well, in a word, boring. Everyone wants to “jump on the bandwagon” as the old saying goes.   What one does, others are quick to copy.                                                                                                                         

At one time, cars & trucks were very distinctive.  Even if they came from the same corporation, each division had its own engines, specifications & body styles.  Today it seems like the only difference is a unique grill & name plate.  So to it seems in the world of arms manufacturing.  I was in a sporting good s store recently and was amazed to see rack after rack of rifles that all seemed too much alike, even though at least 4 different manufacturers were represented.    Don’t get me wrong! Every rifle present was a good, solid bullet launcher.  They all just seemed so…bland.                                                          

How often have you handled or shot a firearm and thought to yourself, “It would have been more functional if they made it like this”, or, “It would look better had they done this.”  Over 2 decades ago, I wrote a prominent US arms manufacturer, and suggested an orange or yellow insert be added to the ramp front sight of one of their revolvers.  I got a polite reply stating they take all suggestions  “under advisement”, but, any change to an existing product entails much study of “all factors involved”.  Two years later they did add that very feature to the model I wrote them about.                                                    

One manufacturer was pestered for the better part of 20 years by stalwart fans to bring back a discontinued, but much loved feature on their rifles.  The factory finally acquiesced; those rifles sell like hotcakes today. One gun writer led the charge for the return of a caliber long dropped by one manufacturer.  They returned that caliber to the line after a 23-year hiatus, and dealers can’t keep them on the shelf, they sell right out.  Honestly though, who wants to wait 2 years, much less 20 years to get what you want?  One answer is; you could do the job yourself.

Anyone who reads SurplusRifle.com knows Jamie, Ted & I are the original “Do-it-Yourselfer’s”.   However, some jobs simply aren’t within the reach of the Do-it-Yourselfer.  Even if the home gun tinker has all the required skills, he may not have all the required equipment, tooling or space.  I would love to have a “Bridgeport” style Jet Machine with digital readouts, an arc-welding rig, and a long bed lathe.  Of course I would also need a complete set of tooling for each machine.                                                                 

I just don’t have an extra $50,000.00 lying around the house.  Besides, who has room for all that equipment?  I would also have to move my wife’s SUV out of its side of our double garage.  Well, you don’t think my SUV is moving…do you? ;-)  All joking aside, most of us simply don’t have the room, or can justify the cost of equipment that would only get used occasionally                                       

When you have a project in mind that requires steps you don’t have the equipment or skills to complete, it makes sense to hire out those parts of the project to someone you trust, someone who’ll do good work and deliver that work in a timely manner.   The last time I wanted a special rifle assembled, the E.R. Shaw Company did the work.  I just could not have been more pleased with the attention and the quality of workmanship they lavished on my Siamese Mauser.  They did a superb job converting and barreling it to 45/70. See article http://surplusrifle.com/shooting/bigboresiam/index.asp.  So, this year I had a hankering for another special rifle.

What I had in mind was a heavy barreled sporter rifle built around a Model 98 type action, (what else?) in caliber 7mm-08 Remington.   I have always had a fondness for the 7mm bore size.  The Spanish were light years ahead when they specified the 7X57 cartridge, and selected the Mauser for a new infantry rifle.  I could have specified the 7X57 just as easily for this project. However, since the 7mm-08 Remington has a case length of 51mm vs. 57mm of the 7X57, a lot more length will be available in the magazine area of the model 98-type action.  This will give me a lot of room to play with bullet seating depths.   The 7mm-08 Remington operates at a higher pressure then the 7X57 in factory loads.  Since I’ll be using handloads exclusively, I have the option to put together mild loads that amble along in 7X57 class, or I can load (safely of course) up to 7mm-08 Remington velocities.  Let’s take a quick look at the 7mm-08 Remington ’s history.                          

Experimenters were looking for a new silhouette round in the 1970’s.  The .308 Winchester was delivering the goods in silhouette.  However, a silhouette match requires 40 rounds.  It took a toll on a shooter’s shoulder after firing 40 rounds of  .308 Winchester.  What was needed was a round capable of reliably taking down the iron, without killing a guy’s shoulder over the course. 

The versatility of the 7mm bore size and its high ballistic coefficient was well known.  Many makers of early silhouette rifles simply produced arms built around a strong, modern action, chambered in 7X57, and operated them at pressures far in excess of factory fodder. However, 7X57 brass was hard to come by.  In those days, factory “bulk” sales didn’t exist!  New, unprimed brass could be had, but only in 20 round boxes.  In the 70’s, buying a 20 round box of empty brass didn’t save much over the price of a box of factory-loaded ammo!

The men building the rifles realized the .308 Winchester / 7.62 NATO case was the way to go.  It was extremely efficient, and surplus 7.62 NATO brass could be had for pennies apiece.  But, they wanted that 7mm bore size. Custom reamers and dies were produced and the wildcat round, the 7mm-308 was born.  By operating at a higher pressure, the shorter case was simply more efficient then the longer 7X57 brass case at the same pressure with modern powders. (Note1)

Remington saw the handwriting on the wall.  7mm-308 was extremely versatile.  Not only did it have less recoil, but do to the extremely good ballistic coefficient of the 7mm bore size, it really preformed at all ranges.  Additionally, it was a great hunting round, and very accurate with all bullet weights.  It could do double duty as either a varminter or big game round.  Remington adopted the 7mm-308, extended the brass length 0.020 and it became the 7mm-08 Remington.  (Note2)

Coincidental to my plans, I just happened to have a WWII, byf Code (Mauser-Werke, A. -G., Oberndorf a. / N.) K98 Action.  Now, before someone emails Jamie and complains: “Your writer hacked up a perfectly good rifle for this project, it’s shameful, how dare you!”  Let me state for the record: I found this un-barreled action languishing in a small gun shop 18 years ago.   The complete bolt has matching #’s, however, that bolt doesn’t match the receiver serial #.  The trigger guard/magazine’s serial # doesn’t match either the bolt or the receiver. 

While the action sure isn’t pretty, and the majority of #’s don’t match, this action is extremely smooth when operated, and everything fits rather well.  The price was right; so I picked it up and put it in my parts/hardware stash.  This action is a perfect candidate for my heavy sporter project.  (Note.3)                                                                 

I considered barrel profiles while contemplating the specifications for this project.  Some shooters feel the shorter & lighter a barrel is, the better.  Many factory rifles are chambered in powerful cartridges; then hobbled with a short barrel that simply cannot take advantage of the potential the chambering offers.  Powder being burnt in a brilliant muzzle flash and thundering report from a potent “magnum” round may seem impressive, but offers no real advantage over the standard cartridge in the same bore size.              

For those who like short & light when it comes to barrels, I’ll not oppose you.  However, please consider the following facts:                                                                                      

●All else being equal; the longer a barrel is, higher velocity will be realized.                      

●All else being equal, the longer a barrel is, muzzle blast and muzzle flip will be reduced. 

●All else being equal, a barrel of greater diameter has the potential for greater accuracy.  

●All else being equal, the longer a barrel is, steadiness will increase while shooting from the offhand position.                                                                                                         

Now, a longer, heavier barrel may not be the best selection in all situations.  I’m thinking about a man who is considering the first centerfire rifle for his young son or daughter.    In such an instance, the stature & strength of the intended shooter must be taken into consideration.   The same consideration applies to stocks.  A shooter who is small in stature will require a shorter LOP (length of pull) to properly shoulder a rifle, and have proper eye relief for metallic or scope sights.  

Building a rifle together can be a collaborative project.  Including your youngster in the planning stage is fun, not only that, both parent & child will learn things from such an experience. A fellow I know had the factory-original, wood stock of a new rifle (not a Mil-Surp arm) cut & properly fitted for his young daughter.  The stock was topped off with a professional quality metallic paint job in a very feminine color of her selection.   This is absolutely “her rifle”! 

There is another thing to consider when drawing up specifications for a rifle.  The purpose of the rifle, and the general conditions under which it will be fired, should, to a certain extent, guide your choices of components & specifications.  A rifle that will only see duty on the vast, flat plains is a different type of arm then one that will taken exclusively to thick, brushy woods.  A rifle that will never be taken afield, but only used as a silhouette arm is different again.                                                                                                              

Can a “one size fits all” centerfire rifle really work?   Sure, I knew fellows who lived in the north woods who couldn’t give a hang about barrel lengths, cartridges etc.   They’re too busy eating venison steaks & wild turkey from their freezer to wonder if the same old rifle that got them their game every year was “right”!   A few of them mumbled things best not said aloud in polite society when they had no choice but to break down and mount a scope on “old faithful”.  Aging eyes do command concessions.

However, such situations almost always occur when a person hunts in the same conditions all the time, and quite often in the same locations.  They have a favorite tree stand or blind, have learned the movement patterns of the animals in their region, and have usually stepped off the distances from their hiding place to where the game will most likely appear out of the woods.   They arrange things so the single rifle that they have will work under a carefully orchestrated set of circumstances.  But, put them in a different situation with old faithful, and the larder might go empty!                         

Be that as it may, this is to be my rifle; and these are the specifications I have in mind.  Would it be best under all situations?  Perhaps not, but, when you are ordering or building a custom rifle, you aren’t restricted to what’s on the shelf; it’s strictly your choice!

Part II.  E.R. Shaw, Producing Art in Steel

The following specifications were sent along with my K98 action to our friends at E.R.Shaw.

• Supply & fit an E.R. Shaw # 3 contour, 26-inch barrel in 7mm08 caliber.

• Supply & fit a custom bolt handle.

• Lap Bolt lugs into action recesses.

• True receiver & bolt face so they are axially aligned.

• Fit a Timney Sportsman Trigger (set trigger weight at 2.5 lb).

• Replace military leaf safety with a low profile Bueller Safety Lever.

• Drill & Tap the action for Weaver scope bases. (My aging eyes command concessions)

• Bead blast & satin blue the action & barrel.
   

The hardest part of this entire project was waiting for the return of the completed work!

I love being at work & getting phone calls from my wife.  It’s nice to take 2 minutes out of the day to simply chat.  It’s even better when she says: “Honey, UPS delivered a long box for you.  It has a Pennsylvania return address.”                                                        

Of course, it won’t do to go home & simply tear into the box right away, unless you are alone when you get home, in such a situation, tear into that box!  But if others are there, ya gotta be cool, & wait for the appropriate moment to open the box & behold your new project. 

Fresh out of the box from E.R. Shaw! 

It’s hard to believe this is that Mauser action from the first picture!

Low slung safety lever gives plenty of scope clearance.

Timney trigger is adjusted to perfection.

New bolt handle allows plenty of scope clearance.

(E.R. Shaw did not D&T the action for a receiver sight; those holes were in the action when I got it in the 1980’s)

I felt like a kid at Xmas opening that long box! The care, workmanship and expertise E.R. Shaw puts into every job can be seen & felt just by handling their work.

The top of the rear receiver ring now one clean & even surface from front to rear; the clip-loading hump cleanly milled off. The action drilled & tapped for Weaver bases. Nestled between the receiver and trigger guard a Timney fully adjustable trigger. A Buehler low profile safety lever graced the rear of the bolt sleeve. The original bolt handle replaced with a graceful custom, polished handle. Due to the fine job of lapping in the bolt lugs, the bolt just glides home when the bolt hand is turned all the way down. More important, this ensures the bolt & receiver are now fully mated. The bolt face is trued. This ensures it is axially aligned with the barrel. The receiver has been also trued, so that long varmint weight barrel chambered in 7mm-08 Remington has full contact when turned in tight. The bolt body, extractor & magazine follower are polished to a high degree. All this finished in a sleek, satin black. A look thru the barrel disclosed an extremely smooth 8-groove profile. Just how well that barrel's interior was finished wouldn't be disclosed until after the first firing (more on that later).

 

Part III. The Mating of Wood and Steel

Some little time after I had acquired the Mauser action in the late 1980’s, I was at a gun show and spied a used, sporter-type rifle stock lying on a dealer’s table.  What caught my eye was the style, a long, even expanse of nicely figured walnut, without spacers, contrasting tip cap or inlays.  A proper traditional classic style to be sure.  The grip flowed evenly between the fore section and buttstock.   The left side of the buttstock had a shadow line cheek piece.  A checkered steel cap adorned the grip, and a plain, black, Pachmayr “Old English” pad resided on the butt.  A tag tied to the stock stated it was for a Mauser 98.  The barrel channel was cut for a very slim profile barrel.   It was the last hour of the last day of the show.  I ignored the stated price on the tag, and made my one and only offer for the stock.  The dealer accepted my low-ball offer.  It was either that or he could pack it back home.

One nice thing about having a stock around for 16 or 17 years before using it; the wood is well seasoned!   As is usual with most stocks cut for a “Mauser 98”, some fitting is still required, even if an action previously resided in the wood.  This is because so many arsenals in so many countries produced actions.   

The correct procedure is to begin by fitting the trigger guard assembly.  Initially, the trigger guard went in about ¾ of the way.   This underscores the differences between individual components.  Whatever trigger guard was originally in this stock had been somewhat narrower.  It only took about an hour of carefully pairing wood with files & a sanding drum on the Dremel tool, and the trigger guard was seated to the correct position.  Next to be fitted is the barreled receiver. 

Since the previous barrel to reside in this stock was rather narrow, there was quite a bit of material to remove before the receiver and varmint profile barrel assembly could be properly positioned in the stock.   Once again, power tools make this job much easier!  It seems like the barreled receiver is tried and removed 100 times before the barreled receiver is properly positioned.  Between each fitting wood is carefully removed.  The receiver itself was almost a perfect fit.  Very little wood was removed in that area.  The next step is bedding.

3 high-speed tools, the one in the center is clamped down to the board, it’s used with the long, flex shaft attachment. 

The heavy barrel is too wide for the narrow barrel channel, the action won’t seat, time to start removing wood.

These tools make the work go much quicker.

Walnut dust is flying!

Smaller sanding drum contours wood to follow shape of barrel.

A piece of brown paper bag shows that barrel is free floated.

(Black mark on stock is magic marker, a guide for barrel contour cutting)

No matter how carefully a rifle is fitted to wood, no amount of hand fitting can compare with bedding compound.  Even serial numbers and stampings will appear in a mirror image in the cured compound.  There are several bedding products on the market.  The one I always use is Brownell’s® Agraglass Gel™.  Agraglass Gel has the consistency of smooth peanut better.  It stays where you put it.  The action & first several inches of barrel channel need to be bedded in Agraglas Gell, the rest of the barrel channel is free floated.  The reason for bedding the first few inches of barrel channel is Mausers just don’t have that great a thread area.  The bedding compound gives more support to this critical area. 

Best bedding compound there is!

Before we go any further, let’s discuss release agent.  The Agraglas Gel kit comes with a bottle of release agent.  Simply smear it on any surface you don’t want to stick to the bedding compound.  If you forget to use release agent, your rifle is permanently assembled!  OK, what if the bottle of release agent is empty?  Simple fix.  Get a small can of wax-type shoe polish.  Smear it on any surface that you don’t want the Agraglas Gel sticking to.  I did that with this rifle, and it worked perfect.  Others have reported using spray furniture polish, and even cooking spray of the type used in frying pans!  I’ve not used these last two methods, but those who use them report good results.      

I’m out of release agent, no problem though, wax-type shoe polish works!

(Masking tape will keep stock clean if gel oozes over the side of the stock)

Gel in stock to give solid support to first few inches of barrel.

Many feel after the Agraglas Gel mix is spread in the stock, and the barreled receiver (covered in release agent) set into place, the trigger guard should be installed, and the screws drawn up tight.  I respectfully disagree.  We’ve already discussed the barrel thread issue.  Mausers also have a somewhat thin tang.  Drawing screws up tight in soft bedding compound can induce stress in the receiver and distort the tang area.   I simply pressed the barreled receiver in the stock and push down with my hand.  Then it was left for 3 days, this allowed the Agraglas Gel to cure, but not harden completely.  Then the barreled receiver was lifted from the stock and excess Agraglas Gel was be trimmed with a razor knife.  Now the rifle could be assembled.   When the screws were drawn up tight, everything was solid. 

Barreled action set in bedding compound, notice trigger guard & screws ARE NOT installed; pressed in by HAND PRESSURE ONLY.

Check it out, even the # stamped in the barrel can be seen in the gel!

The last order of business in stock fitting is slotting the stock for the new, custom bolt handle.  Interestingly enough, as you can see from the pictures, the stock had also been for an action with a receiver sight.  But the original action had had a straight bolt handle.  There was no slot for a curved handle.  Time to remove more wood!  Black shoe polish is used as a spotting agent.  A collection of power tools and files is used to deepen & contour the slot until the bolt closes without touching wood. 

A large round file starts it off; spotting black can be seen below the file.

The flex shaft makes guiding the sanding drum easy.

Various files were used to deepen the slot.

A rotary burr us used to make curves in the wood.

A closer view.

Back of bolt handle coated with black shoe polish.

Tap bolt handle gently against slot in stock a few times and…

Now you know where to remove wood.

Almost there!

(Interestingly enough, my action had had a receiver sight at one time; and this stock had been cut for a receiver sight in the past!  That’s why there is wood missing to the right of the bolt handle slot.  In the future I’ll fill in this blank spot with a walnut patch.)

After the slot is fitted, polish it up with sandpaper on a dowel rod.

Boiled linseed oil will touch up where wood was removed.

Part IV.  Scoping the Rifle: Bases & Rings

I always use Weaver Bases for gun projects.  Simply put: they work!  Weaver, of course, supplies screws with their bases.  Those screws are the correct length 99% of the time.  However, recall the rear receiver ring had been milled to remove the clip-loading hump?   When I installed the rear base, the tips of the screws protruded ever so slightly through the top of the receiver.  I gently tried to install the bolt and found interference with those screw tips.  Due to Mauser 98 pattern rifles having been produced in so many arsenal’s, in so many countries, for over 60 decades, there was still a good chance the screws may have been too long; even if the rear receiver ring hadn’t been profiled.                                              

Gunsmith screwdriver kit, gunsmith screw kit, Rings & bases.

I have a Brownell’s Gunsmith Screw Kit.  This kit is a great thing to have around.  I simply selected a set of slightly shorter pair screws from the kit, instead of having to grind a bit off the end of the Weaver supplied screws, try them & grind more until they were the correct length.   

Brownells sight base screw kit, the taps are not part of kit.

Instead of grinding the screws at right, I selected the slightly shorter set of screws from the Brownells kit pictured below the base.

Correctly fitting gunsmith screwdriver tightens down the base screws.

Rings are the next order of business.  For decades, gunsmiths have placed shims underneath one base to bring them level with its mate. Sometimes the bottom of one base is sanded to lower it; so it matches the height of the other ring.  If only a small amount of misalignment is present, rings can also be lapped (Note.4).  I however, always use Burris Signature Zee Rings with floating synthetic inserts.   Because the insets float in a bearing surface, NO lateral or side stress is EVER imposed on a scope. The rings come with a matched set of + /- 0 inserts.   Let’s say one base sits a bit lower then the other.  By simply clamping a set of ordinary scope rings tight, the scope tube will be distorted the same amount as the ring heights differ.  That’s a bad thing!  Whenever a scope is distorted, adjustment quality degrades.  A fellow may crank hard on the adjustment turrets, running the reticule almost all the way left and way down, and get the rifle to “zero”, but the zero wanders, there are “mystery fliers” etc.  Burris Signature Rings eliminate the stress issue.        

Bottom half of rings installed and bottom half of floating, synthetic inserts installed, not scope stress here!

Scope, top halves of rings & top floating synthetic inserts.

Rear scope mount.

Front scope mount.

Lets say a fellow installs Burris Signature Rings and with the scopes turrets centered, and the scope points high & right?  We know, due to the floating inserts, there is no stress on the tube, but since the bases are either misaligned or the bases sit at slightly different heights the scope is not pointing exactly to the same place as the barrel.   As in the previous example, the shooter could crank the turrets almost all the way left and way down to achieve zero.  But, since we know the best optics is in the center of the lenses, this isn’t best practice.  What to do?  Burris has our backs on this one guys!   They sell a “Offset Insert Kit”, 1” Pos – Align, part # 626019, that has inserts in + / - .005,  + / - .010, + / - .020.  In practice, one bore sights the rifle, see article http://surplusrifle.com/shooting2005/backinblack/index.asp , and uses the insets in + and - pairs to “point” the scope (with its reticule centered) in the same direction as the barrel.  I had to do this with the subject rifle.                                           

I selected a Bushnell “Trophy” 6-18X (Japan) scope for this rifle.  With an adjustable objective (AO), finger adjustable turrets, very high quality lenses & state-of-the-art coatings, the Trophy Series is one of the true bargains in today’s quality optics market. This particular scope has been tricked out by Premier Reticules.  A fine X hair & 1/8 dot reticle has replaced the scopes “Duplex” reticle.  I initially used + / - 0 insets in both front & rear ring.     When I bore sighted the rifle @ 25 yards, with the scopes turrets centered, the scope pointed high.  This was due to either to manufacturing tolerances when the action was made, the amount of material removed when the rear receiver was profiled, or a combination of both.   I simply removed the + /- 0 inserts from the rear ring and placed a + .020 in the ring bottom, and a - .020 in the top ring half.  The insert set raised the rear of the scope .020, and the + /- 0 inserts in the front ring simply pivoted to allow the scope to point in the same place as the barrel, without imposing any stress on the scope tube!  

There we have it, custom barreled action by E.R. Shaw.  A classic styled stock fitted, bedded and scope mounted by your editor.  The next article in this series (Part II), addresses ammunition, and then the payoff: the shooting range!

Cheek piece & buttpad.

A bit of “liquid paper” so the stamp would show up in the picture.  When a barrel has E.R. SHAW stamped on it; you can be sure it’s simply the best!

(I washed the liquid paper off with spray solvent after taking the picture)

Finished rifle!

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