I spend alot of time on Winchester's and Federal's sites studying ballistics and have recently been looking at the difference (or lack of) between 243 and 25-06. I just find it ironic that many people put down 243 as a viable deer caliber, but the same people find 25-06 acceptable. Yes, there is a difference ballistically, but not enough to condemn one and praise the other. This is just my observation from reading on this site for a few years.

I know several people that use 243 Win for deer, including myself(years ago). I've built a few 25-06's for myself and others and have used them on deer too. Both are nice cartridges but but you can do a lot better. For instance: You can get more velocity from a 100 grain bullet with a 260 Rem than with a 243 Win. And more velocity with a 308 Win with 130 bullets than with a 25-06 with 115 grain bullets.

I am just making an observation in this post. I completely agree that there are better calibers for deer. I have gone though several "phases" in my 25 years of deer hunting and have finally grown out of my "magnumitis" phase. I have hunted the last 2 years primarily with my Marlin 336T 30-30 which suits my hunting situation perfectly, but I have just made a deal for a 308 barrel for my Blaser R-93. I have been using a 300 WSM barrel on my Blaser but got the wild hair for something different.

Duh ! Been saying that for years.
There is no difference, not that a deer could tell. Do you actually realise how much 15 gr. of lead is ? Its nothing. nor the difference in .243 or .257 , again nothing.
I think people look at the size of the whole cartridge and base opinions on that, the 25 does seem to look a bit bigger and I think they think its more powerfull.

Velocity is only one small part of the equation. Yes the 308nwill drive a 130 grain bullet as fast or faster than the 25-06 will drive a 115. However the Sectional density of those to bullets is not even close. The 130 grain 30 caliber bullet is intended for varmits where the 115 grain 25 caliber bullet has a much higher sd and is intended for deer and other medium size game. The 100 grain 243 is intended for deer. The 100 grain 260 bullet is border lime and can be used for either small deer and big varmits. Deer bullets should have an sd of about 200-250. Less than that will cause lack of penetration and more than that for deer can cause lack of expansion. This if the bullets are of about the same construction.

I have shot quite a few deer with the 243 and the 25-06. I have seen much better performance from 100 grain 25-06 bullets than 100 grain 243 bullets. I sometimes think the sd of the 100mgrain 243 is a bit to high and I would opt for the 85-90 grain bullets. I find the 100 grain 25-06 bullet the best for deer however some prefer the 115-120 grain. I have shot several dozen mulies with the 25-06 and Nosler 100 grain Ballistic tip bullets. I have taken several with the 115 grain BT's as well but really can't see much difference in performance.

Thats fine, but you do realise that a 100 gr .243 and the 115 gr .257 will have better SD and BC than those mentioned

I have out-grown my magnumitis too! My next gun will probably be a .243!
I know some say the .243/6MM is too small, while still others will go with something even smaller than the .243/6MM!
To me, the .243 is a great minimum caliber for deer, and the other mid-sized calibers are great too! But, no whitetail, anywhere, REQUIRES a magnum caliber!
I'd say don't use anything bigger than you can accurately shoot, and anything smaller than the .243/6MM, are too small for most hunters! Of course if it's legal, its really up to the individual!

Yes sir !
The only thing a magnum offers is distance. Thats it. nothing else, nada, zero, zilch. It has the ability to keep the velocity's needed for adequate expansion at longer distances. dats it.
If people really understood how bullets kill, youd see the .243 is also a long range rifle. The .243 at 400 yds still has the needed velocity for expansion and penetration. It has the SD and BC of much bigger calibers.
Its my favorite, and its one bad mutha. No recoil whatsoever. Its a point and click type weapon, like a camera. It will hit right where you put the cross hairs, everytime.

heres a nice little read on the .243-6mm


http://www.6mmbr.com/243Win.html

I woulda never thunk it