Mossberg Model 151M
Post War Masterpiece For The Working Man
In 1919, Swedish born Oscar F. Mossberg and his sons Iver and Alan founded the company we know today in a small rented loft. They did so with inventive genius and technical innovation, solid engineering and manufacturing skill, tremendous hard work and a focus on making quality affordable guns. Mossberg’s objective was to give the buyers of their firearms, “More Gun For The Money.”
During World War II, Mossberg had to set aside civilian market production to support the war effort, but they didn’t stop thinking of ways to improve their product line. At the end of hostilities, they applied those new ideas to update their pre-war designs.
The Dawn of Man(nlicher)
The Model 151M was one of these improved products, specifically an improved Model 51M — their immensely popular 15-shot tubular magazine semi-automatic rifle with Mannlicher style stock that first hit the market in late 1939. The “M” in the model designation stood for Mannlicher stock.
A Mannlicher stock runs the full length of the forend and was associated with expensive European hunting rifles. Harold Mossberg understood a great deal of the Mannlicher stock’s extra cost was in the extra-long stock blank required to make it. He patented the idea of using a two-piece stock joined by a simple sheet metal stamping to create a low-cost stylistic facsimile. Consumers must have thought it classed the rifle up, because these stocks remained very popular on the post-war rifles.
The 151M was manufactured from 1946 to 1958. I don’t have hard numbers to back this up, but I’ll bet Mossberg sold more .22 rifles with their faux, two-piece Mannlicher stocks in the approximately 14 years they produced them than the total combined number of all the other sporting rifles sold with real Mannlicher stocks.
The Model 151M had a slimmer stock than the older 51M, a redesigned bolt and improved action with a sturdier firing pin, a new elevation and windage adjustable S-107 rear sight. Most innovative of all were the “V” grooves cut along the length of the receiver’s left and right side to clamp scope mounts onto. This type of scope mount is called a tip-off mount and was very popular on low-recoiling rimfires for decades.
Mossberg pioneered the concept of mounting optics without having to drill and tap the receiver. Not only was this more efficient for the shooter, but it made it easier for Mossberg to sell them scopes as a DIY upgrade.
Other 151M features carrying over from the 51M were Mossberg’s excellent adjustable rear peep sights. They could be attached by screws at two or three different distances from the eye as best suited to the shooter and folded out of the way when open sights were preferred. The high cost of Lyman peep sights was the driving force behind Mossberg developing their own, more economical designs utilizing stamped steel parts to replace expensive machined components. The substitution of stampings for milled parts became common in military arms developed during World War II, but Mossberg was already there. In fact, if you dismount the action from the stock on a pre-war 51M rifle, you’ll see Mossberg was utilizing manufacturing techniques advanced for the firearm industry at the time. Such techniques included heavy sheet metal stampings in the fire control components and welding the machined feed lips to the magazine tube support running through the buttstock.
When it was introduced in 1946, the Model 151M retailed for $30.90, which is equivalent to $403.24 today. This was Mossberg’s top-of-the-line semi-auto .22 rifle at a time when semi-autos were notably more expensive than bolt actions. To get a real sense of what Mossberg was offering, we need to compare the 151M to one of its contemporaries, the semi-automatic Winchester Model 74.
In 1954, the Mossberg 151M cost $34.95, and the Winchester 74 cost $39.20. In today’s dollars, the $4.25 difference between them equals $46.68. Both were semi-automatic with a tubular magazine in the buttstock, both were equipped with open sights and walnut stocks.
Tale Of The Tape
The 151M had a 20″ barrel and weighed 7 lbs., while the Model 74 had a 22″ barrel but less stock and so weighed 6.5 lbs. The Mossberg 151M cost 11% less than the Winchester but had many standard features that the costlier rifle did not. The Winchester had no sling swivels or mounts for them. Not only did the Mossberg come with front and rear sling swivels, but they were an advanced quick-detachable type of their own patented design.
The Winchester had a 14-round magazine while the Mossberg had a 15-round magazine. The Winchester had a single, exposed front sight post while the Mossberg offered the shooter the option of switching between four different front sight posts with the flick of a fingertip, and the whole assembly was protected and shielded from glare by a removable sheet metal hood.
The Winchester’s rear sight used a conventional stepped wedge for elevation. Mossberg’s rear sight used a clever and easier to manipulate spring-loaded sliding tangent mechanism that permitted more precise elevation adjustments. The rear sight notch could be switched between “V” notch, “U” notch and peep options by loosening the mounting screw and rotating the rear sight notch plate. The Winchester had a slab sided buttstock while the Mossberg Mannlicher stock had a raised cheek piece. Finally, the Mossberg came with a precision click-adjustable receiver mounted peep sight similar in function to the Lyman micrometer adjustable sights of the day costing $6 to $7 in addition to the cost and trouble of drilling and tapping the receiver to mount them.
On top of all those extra features, the Mossberg 151M with its stock sculpting around the receiver and pistol grip is reminiscent of the French Bertheir rifles of World War I, and its molded plastic finger groove trigger guard was a much classier and modern-looking rifle than the Winchester. Without a doubt, it was “More Gun For Your Money.”