in efforts to pare production costs, rifle makers have dismissed as unimportant the details Paul Mauser and his 19-century German colleagues so carefully worked out.
If the box is properly proportioned, a Mauser bolt smoothly laps cartridges from the magazine.
The late master riflemaker Maurice Ottmar crafted this Mauser after German tradition.
Unlike firearms companies now, Mauser designed each magazine for a specific cartridge. Box and follower dimensions were predicated on case dimensions. Paul figured that a staggered column would enable him to fit more cartridges in the belly of a rifle action than would a single vertical column. But they surely wouldn’t feed if stacked like scrap lumber in a box of indeterminate size and shape. Each round needed support, from the box on one side and a cartridge or the follower on the other side and underneath. He decided the stacking angle should be 30 degrees, so when viewed from the end, three cartridges in contact would form the corners of an equilateral triangle.
Paul Mauser may have determined proper box width by trial and error. He may also have multiplied the cosine of 30 degrees (.866) by the case head diameter, then added the diameter to that product. For example, an 8x57 case measures .473 of an inch across the rim. So .866 x .473 = .410 + .473 = .883. Theoretically, that’s the correct inside rear box width for any cartridge deriving from the 8x57 case. But cartridges taper, and so must a magazine. The same formula yields proper box width at the point of shoulder contact. Adding an extra .003 of an inch or so for oversized or dirty cases makes sense.
A box designed for one cartridge works for others with identical front and rear diameters and the same span between them. Interchangeability is limited according to Mauser’s thinking. A 7.65mm rifle rebarreled to 30-06 needs a longer magazine, and also one that is wider up front. A 7.65 box measures .80l of an inch wide at the shoulder of an ‘06 round. A properly-engineered 30-06 magazine is .822 of an inch wide there. Triangles between cartridge centerlines get steep when the box is too narrow, and rounds tend to cross-stack.
Paul Mauser also relieved the box sides slightly, from just ahead of the cartridge base to just behind the shoulder, so there would be no contact between box and case body. He lavished equal attention on the follower, which on an original 98 mirrors the box taper. The width of its lower shelf matches that of the case, with a 61-degree step between upper and lower shelf. The top shelf is high enough to touch the next-to-last cartridge without lifting it off the last round in the stack (it’s half a diameter above the lower shelf at base and shoulder). The follower has a slope to follow case taper and keep the cartridges level in the box.
Side clearance for a follower is crucial. Custom gunmaker D’Arcy Echols, who is careful to follow the Mauser doctrine in lockstep, makes his followers .060 of an inch narrower than their boxes so they can wiggle. That’s especially important for the last cartridge. "Floorplates machined to hold the Mauser magazine spring tightly don’t work," he says. "I made one once – figured Mauser’s machinists were just sloppy in cutting spring slots .180 of an inch too wide at the rear. They most certainly were not! Those springs are supposed to shimmy back and forth. If the spring can’t shuffle a bit as the bolt strips a round, it twists; and the follower tips or ends up sideways or both." He adds that while follower length is not critical, a follower that’s too short "dives." A follower with too much end-play in a magazine can also bang the front of the box sharply enough to mar it under recoil.
Receiver rails position the cartridge for pickup by the bolt. Because Model 1898 rails are of machined steel, only severe damage or alteration will affect their function. The lower edge of the 98’s bolt face is milled flush with the center of the face so the case head can slide up into the extractor claw. Thus begins "controlled-round feeding," with the cartridge snatched to the face of the bolt as soon as it pops free of the magazine. At the turn of the century, this arrangement made sense because it prevented infantrymen from double loading, or stripping a second round after chambering one and, in the press of battle, reflexively cycling the bolt again before firing. An extractor that grabbed the case right away would eject it on the pull stroke, clearing the chamber.
This Mauser in 404 Jeffery is ready for fitting and finishing. Note the classic straight bolt handle.
Checking the feeding of a Mauser in the shop of D’Arcy Echols, Wayne doesn’t expect malfunctions.
Two protrusions bracket the ejector groove on the left side of the 98’s bolt face. They’re cartridge support lugs. The lower lug is precisely angled to guide the rim of the cartridge as the magazine spring pushes it up into an open breech. This lower lug must herd cartridges from both sides of the magazine into the center of bolt travel and coax the case rim into the extractor claw. Once there, the case head is held tight against the claw by both lugs.
Case extractor grooves vary in depth. Weatherby brass from Norma is .010 of an inch deeper there than Remington’s Weather-by brass. Mauser extractor claws should spring .004 of an inch under tension, so on a custom rifle, a claw fitted to Norma cases will prove too tight for Remingtons, and one fitted to Remingtons will fail to grip Normas. In neither case will the extractor provide positive controlled-round feed.
Paul Mauser purposefully did not engineer his extractor to jump over the rim of a single round loaded by hand. But the 98 has about .030 of an inch extra clearance broached in the right lug raceway of the receiver ring. The extractor claw, which subtends about 20 percent of the rim’s arc, jumps the rim when the rear of the extractor is pinched to the bolt body. To prevent cases from slipping from the extractor’s grasp, Mauser undercut the extractor tongue and its groove in the bolt so that force applied during difficult extraction would sink the claw deep into the extractor groove.
The Magnum Mauser remains queen of the long actions and a popular if costly choice for big-bore custom rifles. It is roughly .375 of an inch longer than the military 98 Mauser action. For many years before the Second World War, Magnum Mausers were exported to Britain, mainly through Rigby, which supplied other London gunmaking firms too. The actions were machined in Oberndorf for specific magazines. Chambering determined not only internal box dimensions but also the width of the receiver recess. Fat rounds like the 416 Rigby couldn’t be stacked in regular fashion because the receiver wasn’t wide enough. The huge 11.2x72 Schueler and 500 Jeffery (12.7x70) could not be placed in a double column at all. They rated a four-round, single-column magazine.
After World War II, Mauser "Werke" (works) became "Waffenfabrik" (arms factory), and Mauser’s business shifted toward the sporting trade. U.S. agent A.F. Stoeger, Inc. of New York assigned numbers to the various Mauser actions. By the late 1930s there were 20 in four lengths: magnum, standard, intermediate and short (kurz). The short action had a small receiver ring and was factory-bar-reled for three cartridges: the 6.5x50, 8x51 and 250 Savage. Magnum and kurz actions were made strictly for sporting use. Mauser did not adopt the Stoeger numbers 1 through 20, but they remain popular designations among collectors. Some Mausers had a square bridge, the hump serving as a scope mount base. Those not machined to take scope rings were checkered on top. "Double square bridge" Mausers feature a second hump on the receiver ring.
Many military 98s have been barreled to long belted rounds like the 300 H&H, but this practice has few advocates now. Lengthening a magazine means trimming the feed ramp, even after moving the magazine back as far as is practicable. The short ramp forces steep entry angles on the cartridges. Ramp work takes metal from the bottom locking lug abutment, weakening it. Moving the magazine rearward
