450 Marlin

Fire Arm






: Marlin 1895

: 18.5 inches

: 1:20 inches

: 24 X

: 50 yards

: 10

Click for detailed 450 Marlin Tech drawing
Click on figure to access ANSI
technical cartridge drawing

A commercial cartridge, introduced at the 2000 SHOT show, introduced as an answer to the industry's long standing 45-70 conundrum. Another in a 130 year tradition of 2.55" OAL, viable in a Marlin 336/1895 action, cartridges. A joint effort by Hornady and Marlin; development of the cartridge led by Mitch Mittelstaedt of Hornady.

Although the external upper body dimensions of the 450 match the 45-70 Gov, given the heavier brass of its 375 H&H roots the case capacity of the 450 is approx 3+ grs less than the 45-70: 73.8gr (of water, full case, 53.2gr, with a bullet seated .500", vs, 77.0 and 56.2gr, respectively). The 450 Marlin is the smallest .458" commercial rifle cartridge introduced in the last 100+ years, yet it fills an important niche. In comparison, the full case capacities of other .458's run: 450 Alaskan, 85.1 gr; 458 Win Mag, 87.4 gr; 45-90 Win, 89.9 gr. Of note: the 450's capacity is quite similar to that of the 458-284 wildcat, at 75.7gr; and the 458-350 Rem mag at 73.0gr. The largest .458's will offer 120+ grs of capacity.

Although the 450's web/rim design appears to be that of the 458 Win Mag (or its parent, the 375 H&H), in fact it is a new design by the Hornady team. Two design goals for the 450 were: that it would not chamber in a 45-70, nor a chamber of another 375 H&H belted magnum derived cartridge. Any belt design would have precluded the chambering in a 45-70; but by adding an extra wide belt, the 450 also precludes the chambering in a 7mm, 300, 338 Win Mag. As such, although others regard the 450 as a commercialized 458x2" American (by Frank Barnes), this author would rather describe the 450 as a new cartridge, designed by Mittelstaedt et al.

In a real world comparison, the 450 is a lesser cartridge than a modern load (Marlin1895) 45/70, and by as much as 500 fp's. Although the two cartridges, if chambered in same barrel length firearms, will show the Marlin generating 1-2% less muzzle energy; as of yet, and with only one counterexample so far, the Marlin is being chambered in performance compromising short barrel rifles and long barrel pistols. The nominal 45-70 barrel runs 22-26". The 1895M Marlin, the premier 450 Marlin rifle, has a 18.5" barrel, ported back to 16"+. In an Encore or Striker, 15" is the norm; in a Magnum Research BFR, 10"; and likewise in a Phillips & Dodge wheelgun. In the handcannons the 450 is down 1000-2000 fp muzzle energy from a 45-70. The only counterexample to date is the 22" H&R Ultra Hunter single shot.

Nominal bullet diameter is .458". Reloading dies are offered by RCBS. SAAMI lists the maximum average pressure at 43500 psi.

© Copyright Gregory J Mushial 1997-2002