B & R Photography

The .300 RCM better known as the .300 Ruger Compact Magnum is said to be one of Steve Hornadys favorite cartridges. Designed in 2007 the 300 RCM was designed during the era of the short fat magnum cartridges. Following in the path laid out by cartridges like the 300 WSM or 300 RSAUM. However, it had differences and was designed to be shot in a short-barreled rifle. Making easy to pack and lightweight.

When it was designed the goal was to duplicate 300 Win Mag performance out of a shorter package. Unlike other cartridges that had the 404 Jeffery as the starting cause Hornady and Ruger decided to use the very popular and fantastically designed 375 Ruger case. They shorted the case to 2.1 inches long and gave it a 35-degree shoulder.

Unlike other short magnums of this time the .300 RCM was designed so the case head and the case body where of the same diameter. This made it really effective at fitting into actions already designed and didn’t require any major modifications. One thing that still blows my mind to this day is that the .300 RCM has a great case capacity than the 300 H&H Magnum.

If you are a handloader, you can load the .300 RCM with a large array of projectiles ranging in weights from 130 grains all the way up to 220 grains (however at these weights I prefer a .338 RCM). Factory ammo is a different story, you can find Hornady factory superformance line of ammunition in weights from 180 grains to 150 grains. These loadings travel at 3,040 FPS and 3,310 FPS respectively. Originally something that was very difficult to obtain hand loading as the Hornady line of superformance ammunition has special blends of powder. However, Hornady has since released the superformance powder for reloads while it might not be the exact blend that is used in the .300 RCM it will get you pretty close with careful load work.

Now let’s move onto the trajectory of this cartridge. Using the information, I have on hand because I wasn’t able to find a chart readily available. A Hornady 180 grain SST projectile travelling at the posted speed of 3,040FPS, with a zero of 100 yards we get the following drop data.

As far as trajectory goes the

200 Yards: 2.83 inches of drop.

500 Yards: 44.58 inches of drop.

1000 Yards: 296.00 inches of drop.

(Please note the above trajectory information was pulled from https://www.bergerbullets.com/ballistics/php/bb.php )

Short Notes.

Official Name: .300 Ruger Compact Magnum.(.300 RCM)

Year Designed: 2007.

Designed by: Joint effort by Ruger and Hornady.

Parent Case: .375 Ruger.

Rifling Twist Rate: 1 in 12”.

Maximum Point-Blank Range: Roughly 300 Yards.

I hope you enjoyed this brief overview of the .300 RCM and will return next week for our Cartridge of the Week series.

Please remember to always practice safe muzzle control when dealing with firearms and happy shooting.

B