.308 Marlin Express
By Chuck Hawks
The biggest rifle cartridge news for 2007 is the introduction of the new .308 Marlin Express. The .308 Marlin is the result of a collaboration between Hornady (ammunition) and Marlin (rifles). This new cartridge was designed for use in the Marlin 336 (.30-30 length) action and uses an improved version of the LEVERevolution 160 grain boat-tail spitzer bullet introduced last year in the .30-30 Evolution load.
Hornady press information about the new cartridge states:
"Hornady engineers selected the most advanced propellants available with a unique cartridge case design that delivers the most efficient performance ever in a .30 caliber cartridge."
"Thanks to the new propellants, virtually all of the energy of the burn is expended where it belongs--inside the barrel to propel the bullet forward. Cartridge case geometry is optimized to deliver maximum performance in the Marlin 336 action and the 24" barrel of the Marlin XLR sends the bullet to the target faster than any lever action cartridge. Period."
"This amazing cartridge, with new, high-tech propellants, optimized case geometry and a highly refined Evolution bullet is truly one-of-a-kind." They make the following claims for the .308 Marlin:
Right off the bat, let me say that the claim about Hornady brass being of the highest quality is true. And I'll take their word about the new propellants. We'll try to sort out the other statements as we go along.
The .308 Marlin is based on a new case, not a necked-down version of any previous case. It is very similar to a .307 Win. case with the shoulder set back .0998", a neck .005" longer, and a its maximum overall length reduced by .095". It is a rimmed cartridge with somewhat greater performance, as factory loaded, than the .307 Winchester and .300 Savage. Its advertised ballistics fall between those cartridges and the .308 Winchester.
The new cartridge was necessary because the .300 Savage uses a rimless case and Marlin wanted a rimmed design for their 336 action. The .307 Winchester could not be used because its neck is too far forward to grip the shank of the new LEVERevolution bullet with its long ogive. Older rimmed cases offering similar performance, such as the .30-40 Krag and .303 British, are too long to work through a Marlin lever action. So, you see, a new case really was necessary to accomplish what Marlin wanted to do. And it was Marlin's requirements, not the desire to introduce a new cartridge, that drove the project.
The cartridge dimensions are as follows: .506" rim diameter, .063" rim thickness, .4703" base diameter, .455" shoulder diameter, and .3435" neck diameter. The case length is 1.920" with a body length from the base of the rim to the beginning of the shoulder of 1.460" and a 20 degree shoulder angle. The neck is .3082", or one caliber, long. The maximum overall cartridge length is 2.60". The Maximum Average Pressure of the new cartridge is 47,500 cup.
Unlike the older .307 Winchester (essentially a rimmed .308 Winchester case loaded with flat point bullets for use in tubular magazine guns), the new .308 Marlin takes advantage of Hornady's development of the LEVERevolution flex-tip spitzer bullet concept. This has been re-optimized specifically for the .308 Marlin, to give a flatter trajectory and greater retained velocity and energy down range. The new 160 grain .308 Marlin Evolution bullet has a longer ogive and a higher ballistic coefficient (BC .400) than last years .30-30 Evolution bullet. (The 160 grain .30-30 Evolution bullet has a BC of .330.) It is primarily this bullet, combined with the use of an advanced propellant, which allows the .308 Marlin to out perform the .307 Winchester.
The newly revised 160 grain Evolution bullet has already proven to be a good one. Reports from the field have been very positive. It has been used to cleanly harvest a variety of medium and large game from antelope to elk. (You can visit the Hornady web site at www.hornady.com to see the results of hunts using this bullet.)
Hornady ballistics tables for the new .308 Marlin call for a 160 grain bullet at a muzzle velocity (MV) of 2660 fps and muzzle energy (ME) of 2513 ft. lbs. Here are the down range velocity and energy numbers: 100 yards = 2430 fps/2111 ft. lbs.; 200 yards = 2226 fps/1761 ft. lbs.; 300 yards = 2026 fps/1457 ft. lbs.; 400 yards = 1836 fps/1197 ft. lbs.
Those are impressive numbers and they put the .308 Marlin firmly into the category of all-around cartridges suitable for CXP2 (deer class) and CXP3 (elk class) game. I would have no qualms about hunting deer and elk with the 160 grain Hornady LEVERevolution load in my new Marlin Model 308MXLR rifle.
The trajectory of the new load looks like this for a rifle with a scope mounted 1.5" overbore: +3" at 100 yards, +1.7" at 200 yards, -6.7" at 300 yards, -23.5" at 400 yards.
Reloading data for the .308 Marlin is not available at this time. Reloaders are unlikely to be able to equal the factory ballistics of the .308 Marlin in any case, because the powder Hornady is using to attain this performance is specially formulated and will not be made available to reloaders. And Hornady has no plans to sell the new .308 Evolution bullet (BC .400) in the foreseeable future. Some day, maybe, but not soon.
The .308 Marlin kicks less than the .308 Winchester because it burns less powder and fires its bullet at slightly lower velocity. On the other hand, it does not quite equal the performance of the .308 Winchester. The latter is factory loaded by Hornady to drive 165 grain bullets at MV's between 2700 fps and 2880 fps, depending on the specific load.
Frankly, we have too many redundant new cartridges, including all of the SAUM / WSM / WSSM numbers and the .30 T/C, but the .308 Marlin is a genuinely useful number designed for a specific reason. Since it was designed specifically for the Marlin 336 action it may not have the broadest range of application, but at least it has a valid purpose.
The .308 Marlin Express joins the select group of "ideal deer cartridges," and surpasses them all in performance. I think that it is going to become a surprisingly popular and long-lived cartridge. For more information, see the Guns and Shooting Online review of the Marlin 308MXLR rifle in .308 Marlin Express caliber on the Product Review Page.
Copyright 2006, 2012 by Chuck Hawks. All rights reserved.