I have a new rifle customer asking my opinion of what cartridge he should select from those I offer. I mentioned to him how I had surveyed my LRH members in a POLL for their opinion of favorite long range hunting cartridges. He indicated some interest in the 300 RUM and based on how he describes his needs I said either the 300 RUM or the 7 Dakota would serve him well.
He asked me how the Dakota compares to the 300 RUM. I explained that I have been a proponent of the 7mm bullet caliber since Warren Page wrote about Remington's introduction of the 7mm RM in the 1962. My first bolt action rifle was in this cartridge a year or 2 later. I knew next to nothing about ballistics but simply reading the drop table and velocities told me the skinnier bullet retained velocity better than the 30-06 and had less drop as a result.
Anyway, the following is what I told Bryan in an email this morning.
In order to select a cartridge for your new Long Range Rifles, LLC gun you asked me for a comparison of the ballistics between the 7 Dakota and the 300 RUM. Both are great cartridges and will do a fine job for your needs.
There are 4 images attached that show the velocity, wind drift, drop in minutes of angle, and energy.
The 300 RUM uses about 20 grains more powder for the 210 grain Berger vs the 180 grain Berger for the 7 Dakota. I used the 210 for the RUM comparison since that would perform the best at 1,000 yards over a lighter 30 caliber bullet.
I used an Excel spreadsheet that I developed to compare recoil. Recoil will be about 50% greater with the 300 RUM than with the 7 Dakota since the rifles weigh the same but the RUM has more powder, heavier bullet and same initial velocity.
So for 50% more recoil with the 300 RUM you get roughly the same ballistic performance except for higher energy with the 300 RUM -- which is so high with both cartridges that the difference in energy is academic.