Magnumania
As I recall, "magnum" is a term that was coined by Smith & Wesson back in 1935 when the .357 Magnum was born. Now anything with the word “magnum” associated with it is touted to be bigger and better than any of it’s lesser brethren. Gun owners eat it up too. Just about every new Super Turbo-Charged Nitro Express Heat-Seeking (caliber of your choice)Magnum is readily accepted by the shooting community and it is often agreed that the new brainchild fills a gap between calibers that is long overdue regardless of how many other “magnums filled the same gap earlier.
One of those is the 7mmRemington Magnum. This cartridge has been around for a long time. Since 1962 to be exact. It is a wonderful cartridge that is suitable to cleanly harvest any big game animal in North America and many species of African game as well. It is accurate, flat-shooting and hard-hitting. However, if we do just a little checking we’ll find that the 7mm is not THAT much better than many other standard cartridges and maybe not quite a good as some of them.
A few of the things that I find objectionable about many of the magnum cartridges is the fact that they have more recoil, muzzle flash, blast and a higher price tag for the ammunition than a comparable standard velocity cartridge and the energy or velocity advantages are often not worth the pain and expense. If you use the energy listings in any reloading manual, you will find that the old .30-'06 and the 7mm are so close to the same in performance at 400 yds that it's not worth arguing about. Different manuals will vary as to which one's best. Both of these cartridges have less energy at 400 yds than a 170 gr. .30-30 Winchester has at the muzzle yet most agree that the .30-30 is too light for elk even at very close range. Then why, exactly, would it be OK to make a 400 yard shot at an elk with 7mm Magnum but not a 50 yard shot at one with a .30-30?
If one were to use the Taylor factor to compare these two bullet’s “punch” instead of those hokey manufacturer’s figures, we will find that the .30-06 has a decisive advantage given comparable bullet weights. The Taylor Factor is much more accurate and logical when you are comparing two different diameters of bullets. The formula for “energy” that is used in the reloading manuals, does NOT take into consideration the diameter of the bullet. You cannot figure mass without ALL of the factors and you cannot determine how “hard” a projectile will strike without first determining it's mass.
Using the Taylor factor, a 7mm Mag. shooting a 162gr. bullet at 2900 fps will be represented by a factor of 19.06 and the '06, shooting a 165 gr. bullet a 2900 fps will be 21.04. The DIAMETER of the .30 cal. bullet is what gives it the considerable edge more than the 3 grains more weight.
For comparison, a .44 mag with a 240 gr. bullet at 1400 fps comes to 20.5 and a .308 shooting a 150 gr. bullet at 2800 fps comes to 18.4.
The elk probably won't be able to tell the difference but, what I am getting at is, I don't believe that the difference between the two is worth going out and buying a new gun unless you are just looking for an excuse to get a new gun.
By-the-way, the .300 Winchester Magnum, shooting a 180 grain bullet at 2900 fps, comes to 22.9 which is less of an advantage over the '06 than the '06 is over the 7mm.
All three calibers are good, just don't let your friends or some gun shop salesman BS you into something that you may not really want. I get my elk very comfortably pretty much every year with either a .30-06 or a .44 mag.
One can "make" the 7mm Remington Magnum have better ballistics than the '06 by using different barrel lengths and changing other factors but there is really NO significant difference in the two cartridges. If you handload, you can make either one superior to the other one.
Just one example:
There are 5 "max" loads listed for the 7mm Remington Magnum that give a 162 grain bullet 2900 fps in my Hornady reloading manual. There are also 5 "max" loads listed for the 30-06 that sends a 165 gr. bullet downrange @ 2900 fps. Given this particular data, the 7 mm shoots 68.7" low at 600 yards. The .30-'06 shoots 74.3" low at the same distance with a 3 grain heavier bullet. 5.6" at that distance is pretty negligible. At the more realistic range of 300 yards, with a 200 yards zero, the 7mm shoots 7.0" low and the '06 shoots 7.3" low. The difference at this range is mostly academic.
The slightly heavier bullet with the larger frontal area also delivers slightly more punch, but again, it is mostly academic and boils down to personal choice.
Given the MUCH wider range of bullet weights, price and availability of ammo, the logical choice, in my mind, is pretty clear. I’ll stick with the 101 year old .30-‘06.