January 29, 2013
By Jon R. Sundra
At the NRA Show in mid-2011, the Mossberg folks came up with an innovative twist for the company's flagship 4x4 bolt action rifle. Designated as the MVP (Mossberg Varmint Predator), they took a 5.56 NATO version and modified it to accept AR-15 magazines. RifleShooter featured the gun on its November/December 2011 issue, and the gun was enough of a success that in 2012 the firm expanded to an MVP series by adding 18.5- and 20-inch semi-bull barreled Predator versions to join the original 24-inch iteration. The Varmint version sports a bench/prone style stock with a vertical grip, while the newer Predator models wear a traditional classic-style sporter stock perfectly suited for general use.
To get a traditional twin-lug bolt action rifle like the 4x4 to accept AR magazines is not as simple as one might think, for it entailed what was essentially the redesigning of a rifle around an existing magazine — one that's been with us since the M14 service rifle of the mid-1950s. To do so required extensive modifications to the trigger guard/bottom metal unit, the stock's magazine mortise and receiver bedding surfaces, and to the bolt face.
The MVP line was successful enough that Mossberg again looked to the 4x4 but this time to explore the feasibility of converting a 7.62 NATO (.308 Winchester) example to accept the DPMS/M14 style magazine used by the various AR-10 rifles such as offered by Bushmaster, DPMS and Remington to name a few. The result is the newest member of the Mossberg MVP lineup, and prior to its introduction I had the opportunity to use this gun on a moose hunt in Newfoundland — an adventure on which the gun acquitted itself nicely. But more about that later.
Like the Predator, this version of the MVP features the same black-hued wood laminate stock and the choice of 18.5- or 20-inch semi-bull fluted barrels. My test gun — the same one I used in Newfoundland — sported the shorter spout.
In order to get the original MVP Varmint to work with AR-15 magazines, Mossberg engineers came up with what they call a "drop push" bolt; a small, hinged, spring-loaded lip at the bottom edge of the bolt face drops down about 1/8 inch to strip the top round from either side of the staggered column magazine.
When the bolt begins its rearward travel, the lip is free to recede as it passes over the top round in the box, be it on the left or right side. Only on the forward stroke of the bolt does the lip drop down to strip the top round and chamber it.
The bolt on the 7.62 version has also been modified but in a much simpler way. Instead of a drop-lip arrangement, there are two small projections at the five and seven o'clock positions just below and flush with the rim of the recessed bolt face. Apparently, this was all that was necessary to get the 4x4 compatible with AR-10 type magazines. Each projection engages the rims of cartridges stored on alternating sides of the magazine. Simple.
Other than the aforementioned modification, the rest of the bolt is quite conventional, as is the receiver. The bolt starts out as a simple tube, to which a separate bolt head and handle are attached. A one-inch long tenon at the rear and integral with the bolt head slips into the bolt body and is held there by a cross pin, which has a hole through its center to allow passage of the firing pin.
At the rear, the handle is collared onto the bolt body. Other than in minor detail, the overall design of this bolt is virtually identical to that of the Savage 110 series, right down to the plunger-style ejector and an extractor that slides radially in a T-slot in the face of the right-side locking lug. The same can be said of Marlin's X7, for it too is assembled in the same way and with similar components.
And like so many other domestic bolt actions, the 4x4's receiver is also a simple tube that employs a separate, washer-type recoil lug sandwiched between the face of the receiver ring and the barrel lock nut. Again, it's the same basic design as found in the Savage, Remington and Marlin.
For a nice cosmetic touch, the bolt body is spiral fluted. Prior to assembly, the already fluted body tube is blackened, then put through a radial grinding operation that polishes the outside diameter but leaves the flutes blackened.
As for functionality, the flutes are very shallow, so there's no weight reduction to speak of. The flutes do, however, reduce frictional surface area by about 40 percent, which enhances bolt glide. Also, the flutes collect dirt and keep it off frictional surfaces. And they do look cool.
I'm sure anyone who's ever examined a 4x4 has wondered what the hell the goiter-like projection on the left side of the bolt shroud is for, because it appears to have no function whatsoever. Without going into the historical and legal aspects of it, suffice to say that this unsightly protuberance is there to prevent a decocked bolt from being reinserted into the receiver.
The two small projections jutting downward from the lower edge of the bolt face enable the MVP to use AR-10 detachable magazines.
The MVP's magazine release latch is part of the housing, not the box itself. Magazines snapped into place smartly, although the author would prefer a flush fit for hunting.
The barreled action mates with the laminate stock courtesy of a stout polycarbonate bedding chassis.
The projection on the shroud prevents an uncocked bolt from being inserted into the receiver.
Under certain circumstances, if a bolt is dropped onto a hard surface or the bolt shroud is rotated to where the firing pin decocks, the nose of the firing pin projects from the bolt face. If it were possible to fully insert the decocked bolt with a round in the chamber or magazine, slamming the bolt home could fire the chambered round with the bolt out of battery — as in, unlocked. Apparently, prior to Mossberg's acquiring the manufacturing rights of this rifle from Charter Arms (which originally designed it and produced it for a short time), someone managed to do it.
When I said earlier that converting a rifle to an existing magazine requires more than meets the eye, only upon disassembly can one appreciate that fact. Removing the barreled action exposes a stout polycarbonate chassis that serves as a bedding platform for the receiver, as well as the housing for the magazine. The release latch is located on the housing itself rather than being part of the magazine. I actually prefer the opposite arrangement — the latch mechanism being part of the magazine rather than the housing — but it's no big thing either way.
With the barreled action out of the stock, the Lightening Bolt Action trigger is exposed and can be user-adjusted with an ordinary screwdriver down to a light two pounds. For me, two pounds is about right for a varmint rifle, but for a hunting rifle I prefer three pounds, which is exactly what the test gun's pull registered.
This trigger is conceptually similar to Savage's AccuTrigger in that a thin blade projects forward of the finger-piece through a vertical slot in its center. This blade must be depressed before the trigger can move rearward and fire the gun. The Marlin X7 and the new Ruger American have similar fire-control systems. A two-position side safety blocks trigger movement. The LBA trigger is now standard on all iterations of the ATR and 4x4.
The black-hued laminated straight-comb classic stock is nicely done and fully shaped at the rear of the grip. Instead of checkering, the grip and fore-end panels are stippled. A thick recoil pad and swivel studs complete the stock furniture.
My only criticism stock-wise is that the fore-end measures a full two inches wide, which is fine on a varmint/target rifle but too much of a handful on a sporter. This corpulence is dictated by the width of the magazine housing. Still, it would be possible to slim down the fore-end starting just ahead of the front action screw. I'm not sure how that would look, but it would definitely feel better, particularly for a small hand like mine.
Pre-installed Weaver-type bases come standard on MVPs, so ring type for scope mounting is simplified. I chose Millett windage-adjustable rings to mount a Swarovski Z3 3-9x36 scope. This is the smallest and lightest in the Z3 line, being only 12 inches long and weighing a mere 12 ounces. With the Z3 aboard, the test gun weighed in at 8.5 pounds lbs. If that seems heavy for a short action 18.5-inch carbine, remember it sports a semi-bull barrel that measures .760 inch at the muzzle, and the stock is a wood laminate.
My range work was a little rushed in preparing for the moose hunt, as the rifle arrived just a few days prior to our departure. However, after the hunt I was able to spend more time with the gun on the range. The venue for the field baptism was Mt. Peyton Outfitters out of Bishop's Falls, Newfoundland. We hunted hard for moose every day, but it was the sixth week of the season, and the rut was over, so calling proved fruitless.
As it turned out, I never got a shot at a bull, but after carrying the gun for eight to nine hours a day for five days, I can tell you its 37.5-inch overall length made it a joy to carry. I sling rifles on my off (left) shoulder with the muzzle down, and it carried through thick cover with minimum hassle and plenty of ground clearance.
Aside from the overly thick fore-end, another issue I'd like to see addressed concerns the magazines. The four-round DPMS-type magazine is of the exact same dimensions as the 10-round box, and therefore both extend some 2.125 inches below the belly of the stock. That's precisely where the balance point of the rifle is when hand-carried. Surely they will come up with a four-round magazine that fits flush, or nearly so.
The fact that Mossberg chose to use the same "MVP" designation for this 7.62 NATO version may cause some confusion because it is neither a varmint nor a predator rifle per se. Rather, it is a highly capable big game rifle perfectly able to take down a 1,000-pound moose.
As for going with the military 7.62 chamber stamping instead of .308 Winchester, it was for the same reason the company chose to use 5.56 NATO for the other MVP: namely, military chamber and throating specs are slightly more generous than for the .308 Winchester, so that under some circumstances firing military 7.62 ammo in a .308 Winchester rifle can produce higher than normal pressures. We're not talking dangerous levels, mind you; it's just that Mossberg felt that going with the 7.62 chamber specs was the prudent thing to do.
All through the sighting in, the hunt itself, and the range work afterward, the test gun performed without a hitch. The magazines snapped into place with a definitive click that can be heard and felt. The magazine can be charged by pushing rounds straight down through the feed lips rather than having to back them under same. And the LBA trigger was crisp and creepless.
As you can see from the performance data, the 18.5-inch barrel can reduce factory (24-inch barrel) muzzle velocity by as much as 160 fps, but I still wouldn't hesitate to use this gun on all but the world's largest non-dangerous game. And with a price of $681, it's as good a candidate as any for the title of Everyman's Rifle.