Here are some notes I wrote while sporterizing one of the Mausers I have worked on:
2) True receiver face, cut shoulders for sights to line up on top
True receiver face [remove fore stock gripping lip], move barrel shoulders until sight dovetail on barrel lines up with top of receiver when screwed in tight. There must also be a relief at the breech. The Turks did .877" dia and .044" deep. I did .877" and .025" deep.
3) Notch receiver for bolt handle
Notch out receiver for bolt handle that Paul welded on, and grind on bolt handle until it goes in notch.
4) Mill off charging hump, cut radius on scope mount
Peen shoulders until they grow back .001" so sight dovetail will line up and not overshoot. Mill off rear charging hump of receiver. My mill only tilts right and left, so the receiver must be mounted in line pointed at the knee. File rear charging hump Grind off sharp edges.. Put valve grinding compound on bolt and fit it to the receiver where stiff. And I milled off .023" from the Weaver S#45 [rear mount] so that it is the right height when dealing with the extra large front ring of a Turk 03
Putting a S#46 on the front ring of a Turk 03, one gets 1.172" height from the flat bottom of the receiver.
Putting a S#45 on the rear ring of a Turk 03, one gets .023" more.
Measuring the thickness of a .390" if on only uses the blade end of the calipers. The error caused by the flat part of the calipers will be to look like .400".
Using a 1" end mill for .5" radius to approx. the shape of the rear ring of the 03 Turk...
Cutting .023 off the S#45 and only measuring the first 1/8" of the top, so that only the blade of the calipers is used, will give the correct mod for the S#45 for Turk 03s.
This explains all the trouble I had with the 7mm Mauser scope mounts last month on a Turk 03. Mount tops are now within .001" relative to the receiver bottom.
Tilt mill head 30 degrees to the right and left. Pinching the recoil lug in the mill vise is not perpendicular to the bottom of the receiver. This causes a downward compression on the shims at the rear of the receiver that helps stabilize when cutting off the hump.
5) Drill and tap for scope mounts, cut chamber with reamer, cut new barrel vise bushing
I drilled and tapped. It seems that someone has modified the drill and tap fixture for 1903 Turks with the charging hump removed. This makes it possible to not alter the rear mount for bolt handle swing clearance, and the front mount goes all the way to the trued face. The bushing and bolt are cut away, and the bolt can only be tightened so far to have the right orientation. I polished and blued the charging hump, bolt handle slot, and trued face. I cleaned the valve grinding compound out of the receiver and bolt. I re cut the sight area for the steady rest by putting the .301" pin gauge in the tip of the jaws in the tailstock chuck where it would be more compliant to match the bore of the barrel. This got run out on the pin, when the barrel was located by the steady rest, at +/- .001".. I got the chamber cut. I vacuumed out the chamber at each ~.050" of chamber cutting, swabbed it out with a Q tip, washed the reamer off in motor oil mixed with used paint thinner, and re coated the reamer with Sulfured cutting oil. I stoned off the end of the reamer and stoned off the end of the #3 Morse /Jacob's taper that I used to push the reamer. The tap T handle that I held the reamer with was handmade and found at a garage sale. I calculated that the case should stick out of the breech by .107", and at .114" I quit. That makes the bolt close on a cartridge, but not on a cartridge with a layer of .005" masking tape. I had to cut a new .900" inside diameter collet of 1.5" round Aluminum for the barrel vice to hold the Remington barrel at the sight bulge. The boring bar could not get in, and I had to make a .935" collet. After I milled a slot with a saw like cutter on one side of the collet making a "C" shape, the inside diameter closed up and held the barrel well, but was hard to get off past the front sight.
The Wheeler Drill and Tap fixture I purchased in 2000 for 1903 Turkish Mausers.
http://www.midwayusa.com/eproductpage.exe/showproduct?saleitemid=603260
The fixture top plate has two holes close together at one end for bushings for drill and tap the rear of the receiver, two hole at the other end further apart for bushings for drilling and tapping the large ring, and two big holes in the middle for bolts that hold the fixture together.
There are 4 mods:
1) The charging hump on a 1903 is so high, it interferes with the top plate. And area in the top plate has been relieved, and is now shinny instead of black anodized.
2) The round bar that fits in the bolt bore of the receiver is long enough so that it interferes with the barrel. That keeps the used from drilling through the barrel. One must unscrew the barrel first. This one has been modified so that a rifle can be drilled and tapped without pulling the barrel, by shortening the bar.
3) The forward bolt of the fixture that hold the pieces together interferes with the notch in the large ring of a 1903 Turk. A new bolt was found and relieved. That is the flat spot on the bolt.
4) The bushing that locates the bolt in the bar interferes with the notch in the large ring of a 1903 Turk. The bushing has been relieved. That is cylindrical part with some grinding done to make a wedge shape.
When the fixture mods are used, and the rear hump has been removed from the receiver, the holes are so far forward that the Weaver S#46 in front is flush with a barely trued large ring and the rear mount is so far forward that it does not need to be relieved for the bolt handle swinging by it's rear right corner.
6) Notch gunstock for bolt handle, grow over cut breech, trigger job
I notched the gunstock for the bolt handle. I used a hack saw, a large diameter rat tailed file, and a flat file. I used to use a chisel, but I think this saved time.
I cut off the stock at the barrel step down. Remove metal on the breech on lathe. Removed too much, squish shoulders in mill vise to grow more breech. Punched line up marks on bottom of barrel and receiver. Squished the barrel vise bushing with slot straight up, for uniform smaller diameter. Hack sawed barrel vise bushing for two 180 degree pieces. Fife burrs off the inside of the receiver from drill and tap. Re tap and die the bolts and holes on the barrel vise, and add oil. Replace trigger spring with wimpy spring. Cut wimpy spring in half and stretch.
7) Glass bed scope mounts
Count Leupold Vari-III 6.5x20x40 adjustments at 3.6 turns side to side and 3.6 turns up and down. Set scope at 1.8 turns in the middle of it's range. That made the aim 1~2 foot high and to the left at 50~60 yards on objective adjustment where no parallax. At 55 yards, 1~2' error is 1.8 ~3.6' error at 100 yards = .006" ~ .012" error at 5" between scope mounts. This suggests that I should have cut .014" and not .023" off S#45 rear mount. Loosen and re tighten scope rings and error to the left goes away. Burrs on the receiver top from drill and tap 6-48 upset metal. File off the burr and there is still .010" height error. This suggests that the bolt bore is out of parallel with the bottom of the receiver by .010"/5". I put two tiny .005" masking tape pieces on top of the receiver in the centered in the S#45 area. I covered the receiver with masking tape, .010 from the edge of the mounts. I mixed the Devcon Steel Putty at 62 degrees, 2.5:1 volume ratio, and it was good. The mount screws were loose, the rings were tight on the scope and the mounts. The bore lined up with the cross hairs on the target, and the epoxy set up. When hard, the masking tape was taken off the receiver and the mount screws were tightened. The oozed epoxy is chipped off with a screw driver, leaving a fillet at the base of the mounts.
8) Glass bed barreled action into stock
I milled down the recoil cross bolt to get clean, rough, and make room for epoxy. I counted 5 3/4 turns on the front guard screw and 4 1/4 on the rear while in the stock. Out of the stock, the front was still 5 3/4 turns, so something must be done. 4 layers of masking tape on the rear sight bulge on the barrel to keep the action elevated so the front guard screw will not bottom out when tightened. Put foam rubber up the front action screw hole in the stock to touch the receiver recoil lug and stop epoxy from leaking or spreading. Heated barreled action with heat gun. Glass bedding set up: barreled action, stock, foam rubber, squeeze clamp on rear tang of receiver to bottom of stock, front and rear bench bags, drip pan beneath. Some epoxy squirted out the mag well, but did not drip.
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Steve