I’ve been thinking that I’d like to add a bigger rifle to my collection. My future father in law has a close family friend with a ranch down in South Texas with a 1000 yard range and an endless supply of pigs. For a kid raised in the country, that is as close to a dowry as you can get. However, my little .243 just doesn’t have the stones to reach out past about 500 yards and I sure wouldn’t feel comfortable taking a little piggy at any distance beyond 100 yards. So, I feel justified in my need for a new gun to bring to the ranch . . .
If you haven’t spent some time playing with Winchester’s Ballistics Calculator, I highly recommend it. While it is not a replacement for field results or a more customizable calculator like the one from Knight Armament, it is still a pretty slick (and free!) tool to help you get your bearings on a ton of cartridge profiles.
I used it one evening to take a look at my four potential candidates. In no particular order, .25-06, .270, .30-06, and .308. I chose these for their diversity, general availability, and extensively studied characteristics. I modeled all of them on the Ballistic Silvertip Bullet that I have come to know and love. I made an effort to get the bullet weights as close as possible to each other. Your results might vary based on what size bullet you use. Here are my simulated shooting conditions.
I included .243 in as well to establish a baseline for what I use now. My 95 gr. .243 round leaves the barrel with 2025 ft-lbs of energy, but by 400 yards has dropped almost 19 inches below point of aim, has drifted a little more than 12 inches, and has just a touch more than 1022 ft-lbs of energy.
Taking a look at the three metrics for the four cartridges (click to expand), it becomes apparent that if you want to put holes in paper, .25-06 is a worthy contender. Given that .270 and .25-06 have .30-06 as either an inspiration or a parent case, their terminal performance should come as no surprise.
Line of Sight Drop
1.) 115 gr. .25-06 (18.6 inches)
2.) 130 gr. .270 (18.9 inches)
3.) 150 gr .30-06 (21.2 inches)
4.) 150 gr. .308 (22.8 inches)
Wind Deflection
1.) 115 gr. .25-06 (10.93 inches)
2.) 130 gr. .270 (11.37 inches)
3.) 150 gr .30-06 (12.16 inches)
4.) 150 gr. .308 (12.74 inches)
However, I am looking for a cartridge that will impart as much energy as possible to the target animal. And here we can see that .30-06 and .270 are within a few percentage points while .308 and .25.06 bring up distant third and fourth places.
Energy
1.) 150 gr .30-06 (1471.88 ft-lbs)
2.) 130 gr. .270 (1426.48 ft-lbs)
3.) 150 gr. .308 (1369.21 ft-lbs)
4.) 115 gr. .25-06 (1296.48 ft-lbs)
.270 has a lot going for it. Flat shooting, good wind resistance, decent downrange energy. In addition, .270 can be found in any gun shop, Wal-Mart, and bait & tackle place in the nation. It has been studied extensively and manufacturers have created a plethora of cartridges fitted for everything from varmint hunting to large game for use in .270. And if it was good enough for Jack O’Connor, it is good enough for me.
Now, to choose a rifle . . .