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."

"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:

• The most advanced lever gun cartridge ever.
• Performance that rivals the .308 Winchester, but with less recoil.
• The Evolution bullet provides a dramatically higher ballistic coefficient and affords dramatic velocity increases over traditional flat point loads. It also delivers devastating terminal performance over a wide velocity range.
• Advanced jacket/core construction that provides exceptional expansion, deep penetration and weight retention.
• New propellants provide maximum muzzle velocity at conventional pressures for flatter trajectories and greater downrange energy.
• Highest quality cases and primers for consistent shooting in the field.

The .308 Marlin is based on a new case, not a necked-down version of any previous case, although it is very similar to a .307 Win. case with the shoulder set back .0998". 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 cartridge dimensions are as follows: .506" rim diameter, .4703" base diameter, .455" shoulder diameter, and .3435" neck diameter. The case length is 1.920" with a 20 degree shoulder angle and a neck .3082" (one caliber) long. The maximum overall cartridge length is 2.60". The Maximum Average Pressure of the new cartridge has yet to be standardized by SAAMI, but it is likely to be in the vicinity of 46,000 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.  mike martin Reported that in the field hunting has been positive. It has been used to cleanly harvest a variety of medium and large game from antelope to elk. (You can visit long time friends max and don lundquist and read about martins success on antelope  here. to see martins results of hunt using this bullet IN THE NEW 308 MARLIN XLR.)

Hornady ballistics tables for the new .308 Marlin call for a 165 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.

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.