For my part, I have a good bit of respect for the .243 caliber, be it .243 Win, .244 Rem (6mm Rem) or the .240 Wea Mag. I have owned .243 Wins and 6mm Rems and both have been very efficient at killing with one shot. I'll follow-up with a picture for our "doubting Debbies" in a minute.
The only reason I bought a 6mm Rem in addition to the .243 was the ability to load more powder. Yes, I read the previous statements about overbore. Chronographs don't lie. My 6mm Rem handloads, with 95 Gr Nosler Partitions exited the 24" barrel of my M700V at 3,371 FPS!!! Check your ballistics tables and you'll see that exceeds the book-listed max by a full 200 FPS. It also exceed the listed velocity of Weatherby's .240 Wea Mag by 109 FPS, and that with a 2" shorter barrel to boot!!!!! It can't have been too d@mned overbore now can it?! I used compressed loads of AA3100, a fire-formed, turned and neck-resized-only cases, run through custom-made dies, Fed 210 bench rest primers and the Noslers. And yes, it grouped 3/8" at 300 yards. Had to put that back in this thread for the haters. (No, I will not disclose the amount of powder I used for the charge as it far exceed the max loads).
For me, and based on my hunting experiences to 400+ yards with .243 Calibers (Win, Rem and Wea), they all will kill a deer dead with one shot. Yes, it may run for 100 yards, but trust me, it'll be meetin' up with death soon enough.
The following picture is the severed heart (as in blowed clean off) from a 95 Gr Nosler partitian, handloaded to 3,371 FPS. The shot was dead-on, center of the breastbone on a deer at 300 yards. As you can see, it blew the heart clean free of the "attachment points" so to speak. When we cut the deer open to gut it, the heart rolled out on the ground. The Nosler Partitian was lodged under the skin, just left of the "@nus". It fully penetrated the deer's body-length.
Here's my take...you like the .243 Win? So do I and a heck of a lot of other fellas who have used them, and frankly, we know what we're talking about. You like the 6mm Rem? So do I (repeat). Buy the cartridge that you trust, and can shoot well.
Geno
Pic:
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