Turn an Older Marlin Model 336 Into the New 336 XLR

So what happened to the Marlin 336 that resulted in the new 336 XLR? Once again, we can thank those clever folks from Hornady. About three years ago, they made the .22 WMR all but obsolete with the introduction of the .17 HMR. Last year, they blitzed the whole rimfire industry again with the .17 Mach 2, also known as the .17 HM2 or just the "Mach 2" if you like the sound of it better.

Not to be overlooked in these accomplishments was the cooperation received from firearm makers and the development of anew propellant powder. Those contributions being duly acknowledged here, Hornady’s little V-Max bullet was the ringleader in causing all the upheaval. This year, another Hornady bullet, dubbed the Evolution, is transforming the venerable .30-30 into a longrange high-velocity game dropper. The new slug looks like a larger version of the V-Max. It’s not.

The V-Max is a hard-nosed little demon; the new Evolution bullet wears an elastomer tip that flexes and is being made in .30-30 and larger calibers. Until the development of the new bullet, tube-fed lever-action rifles were obliged to use roundor flat-nose ammunition exclusively in their magazine tubes. The reason being the danger of a pointed bullet impacting the primer of the cartridge ahead of it due to recoil action, and thus touching off a doomsday chain reaction in the tube.

By combining the Evolution bullet with a centerfire case, we now have around of LEVERevolution’ ammunition (correctly pronounced "Lever-Revolution"). No smokelesspowder lever gun presently made or to be made needs to be limited to using roundor flat-nose ammo from this moment on. That’s a good thing when you consider the ballistic coefficient of a bullet.

The ballistic coeffcient (BC) is a bullet’s ability to overcome air resistance in transit compared to the ability of standard projectiles used to develop ballistic tables. The mathematical formula is: BC equals W/ID 2, with Wbeing the bullet weight, I its form factor (spire point, round nose, etc.), and Dbeing the bullet diameter. The BC of a 160-grain .30-30 Evolution bullet is 330. An average conventional dull-nose 150grain slug comes in at 186.

This is all very interesting if you want to reach for your slide rule or punch up a ballistics program on your computer, but how do those stats convert to actual performance out of a 24inch lever-gun barrel with factory loads? Hang on to your hat. The muzzle velocity produced by a .30-caliber 30-30 is immediately apparent. The difference in muzzle velocity and downrange performance is remarkable.

They also eliminate the danger of a chain-reaction ignition in a tubular magazine. 30-30 LEVERevolution cartridge. Upon seeing it for the first time, the author wondered: "Why didn’t I think of that?" LEVERevolution factory cartridge is 2,400 feet per second. The roundor flat-head factory cartridge exits at under 2,200 feet per second. Downrange at 250 yards, the .30-30 Evolution is still tearing along about 400 feet per second faster and leaves a wound cavity 50-percent larger than a dull-nose slug.

Comparative data is equally impressive for the LEVERevolution 200-grain .35 Remington, 265grain .444 Marlin, 325-grain .45-70, and 325-grain .450 Marlin. So what does this have to do with the new Marlin 336 XLR rifle? The mechanics of the Marlin 336 XLR are identical to earlier versions of the 336.

It’s disassembled and reassembled in the same way, and those instructions can be found in several reference works, among them, The NRA Guide to Firearms Assembly for shoulder arms and Gun Digest’ s book on centerfire rifles. The schematic is included here, but not for the usual take-down/reassembly reasons. Instead, I’m using the schematic to point out the design changes made by Marlin engineers to enhance the accuracy of the rifle and take full advantage of the LEVERevolution cartridge potential.

And those are changes that you can make, too. The intent of the changes was to reduce stress on the barrel and make it as close to free-floating as possible. This was accomplished in several ways. A half magazine tube (#48) would cause less stress, so it has replaced the full-length tube. The barrel dovetail securing the tube stud (#53) was opened up slightly to reduce tension between the magazine and the barrel.

To reduce pressure between the receiver (#62) and the barrel (#1), the forearm (#25) fit was loosened somewhat at that juncture. The barrel has been Ballard rifled with six grooves and, after consultation with Hornady, was made 2 inches longer for greater accuracy. The other change in (continued on page 16)

AGARAD6 Armorer’s Course, AMG version (pick up from 9/06 issue)

AGARAD6 Armorer’s Course, AMG version (pick up from 9/06 issue)

XLR rifles was made for calibers heavier than .30-30. A dimple was placed in the center of the magazine follower. This encourages the elastomer nose of larger Evolution bullets to stay where they’re supposed to stay.

More specifiacally, it keeps them directly aligned with the cartridge base immediately ahead and avoids a jamming problem that might occur when the round enters the existing bulge at the receiver end of the tube. (At that point, tridge is subject to shifting one or another, which could allow ip of the following round to become wedged between the case rim and the interior of the tube.

This, of course, prevents any further movement to the rear.) The dimple acts as insurance that the bigger cartridges will behave themselves and enter the feed mechanism without canting. Marlin may not want me to mention this, but it isn’t absolutely necessary to own anew 336 XLR to join the LEVERevolution. Any 336 in good condition will do, and do better with the new ammunition.

The possibility does exist, however, that LEVERevolution rounds larger than .30-30 might cause the late-rou ra follow the lead of the Marlin engineers and avoid such jamming. Here’s how you can do it: Remove the inner magazine-tube spring (#52) and follower (#49) by backing out the magazine-tube plug screw (#51) and withdrawing the plug (#50). Secure the follower in a lathe, and install a center drill in the tailstock.

Turning the machine slowly, drill a starter hole in the center of the follower no more than 1/8-inch deep. Widen the hole with a larger drill equal in diameter to the middle of the elastomer tip. Replace the drill with a 1/4-inch-round countersink. Chamfer the hole very carefully, but don’t carry the chamfer depth beyond 1/16 inch.

You simply want to make it easy for the point of the Evolution bullet to find a comfortable home in the follower and like it enough to remain in residence until called upon to enter the receiver. Many years ago, I gave my Marlin 336 in .35 Remington to one of my preteen cousins in Maine. She repeatedly embarrassed her father for many deer seasons thereafter by bagging some nice whitetails while he got skunked.

I plan to call and tell her to send the magazine follower and spring to me so I can enhance it with a dimple. Then she can continue to turn Daddy’s face red at even longer ranges as a "LEVERevolutionary." I may well join her in what I expect to become a growing movement. It all depends eck out some ammo in 894 Winchesters. Previously on duty as a tower-guard rifle in a Michigan prison, it still wears an armory ID of ’10 on its stock.

This ’94 has helped me succeed in the woods many times, and has helped win sporting-rifle matches more than once. I’ll decide whether or not to become a LEVERevolutionary after my little outing with #10. I have a hunch what will happen. From then on, going after game or targets with dome heads in my lever guns will be (pun intended) "pointless." I