.338 Marlin Express (using Hornady bullets)
Date: Aug 14 2014
The .338 Marlin Express was developed by Hornady Manufacturing and Marlin Firearms, and is based on the .376 Steyr case (which Hornady also developed). The case had to be shortened, the shoulder angle changed and necked to accept .338-inch bullets, and finally a semi-rim added. Next a new boat-tail spitzer bullet was developed that featured a special rubberized "FTX" tip to prevent primer set-off when used in the tubular magazine of the Marlin MXLR lever-action rifle. The end result is a modern cartridge capable of pushing a 200-grain bullet to an advertised 2,565 fps and is suitable for hunting moose, elk and bears, as well as African plains game. With a 200-yard zero, it drops 9.7 inches at 300 yards, making it useful in open country. Select loads produced sub MOA, 3-shot groups.
In referencing Hornady factory ammunition, a five-shot string averaged 2,524 fps from a Marlin Model MXLR with a 24-inch barrel.
Bullets should be seated to an overall cartridge length of 2.585 inch (to assure proper cycling through the action), then roll crimped in place to prevent bullet movement when subjected to recoil and magazine tube spring pressure.
Loads containing ball (or spherical) powders should never be reduced below "start" loads, or hang-fires, erratic ignition and pressures can occur.
Outstanding performance (accuracy and velocity) was obtained with Accurate AAC-2520, Hodgdon LEVERevolution and Ramshot Big Game powders. Only standard (non-magnum) large rifle primers should be used, with Winchester primers chosen to develop the accompanying data.
Do not substitute other .338-inch spitzer bullets that have either a lead exposed tip, plastic tip or are hollow-pointed, as magazine tube detonations are probable.