Wyoming requires a 24 caliber of larger. I have seen several elk killed with 243s and all but 2 were good fast kills. The 2 that were not were #1 a bad hit and #2 shot with a bullet that came completely apart. BUT>>>>I have had poor results with several 7MM Mags and 300 Mags when used with bullet that come apart too. I made a good kill on a 5X5 bull a few years back with my 8X57 and the 170 grain SSTs didn't hold up well, but I did drop the bull simply because I got good placements of those bullets. The 8X57 will do anything the 30-06 will do, but I found the 170 Gr SST to be too prone to break up for good deep penetration's. So the shell is not as important as the bullet it's firing.
I do not damn the 243s as "too small". I do think the smaller you go the better you bullet should be and the kill angles are going to be more critical.
So what is the minimum?
That depends on how good a shot you are and what bullet you use, but even though I lean towards larger calibers I have 50+ years of experience of elk killing, and I know from what I have seen a good 243 with a good bullet ,shot well works just fine.
I categorize elk kills in 2 ways. Those I have killed and those I have seen killed when guiding or helping other.
In category #1 the 2 calibers I have seen the most instant or near instant drops from are the smallest one I have used, (the 270s) and one of the largest (the 375H&H) The 270 Winchester has dropped every elk I ever shot with 1 round and not one of them has strayed up after impact for more then about 3 seconds and probably 85% have fallen instantly or within 1-1-1/2 seconds. And my 375H&H is the other "magic-wand" that seems to drop them faster then almost all others except my 270s.
Now in-between I have used 7X57, three different 7mm Mags 300 Savage, 30-06s, 308s, several 300 mags, an 8X57, 338-06s, 338 Win mag, 9.3X74R and then over the 375H&H bore size I have used the 45-70, 458 Win and 416 Taylor as well as 44 mag handguns and 454 Casull handgun, and also 58 and 62 caliber muzzleloaders and 1 with a wood arrow shot from a wood and glass long bow.
So I have used many different guns and a lot of different bullets. But one of the "least powerful" was my 270 Winchester yet it's been super effective for me, far more so then the three 7 Mags and all my 300 Mags when I look at the averages. Many times my big 7s and my 300s did the job with bang-flops but not as often as my 270s did. So for reasons I don't actually understand and for reasons I can't explain, the "little" 270 seems to drop them as well and anything else and quite a bit better then many of the more powerful ones I used. Why? I can't say for sure but what I can say is what I have seen for over 50 years.
I probably averaged 2 elk a year for 50+ years with a few years killing as many as 7 and in a few years getting none. Many years I hunted in 2 states and a few years I hunted in 3. One year I hunted in 4. But 2 per season or maybe a but more (2-1/2?) is about my average.
However in those years I guided I would see 20-35 killed each season. So I have seen what works and what doesn't, and most times the bad results are #1 poor hits and #2 poor bullets, but in 50+ years and seeing many many many killed I have come to the conclusion the actual shell used is not near as important as most people seem to think it is. I would guess that there is a bottom, but the 243 is not below it. So far the smallest center fire rounds I have seen elk killed with is the 243 Winchester. No one I know has ever tried it with a 22-250 or a 223 but I bet if you used proper bullets those would work too.
The 270 bore size is the smallest diameter I ever killed elk with, but I have seen it done very well with 26s (6.5X55s, 260s 6.5 CMs and 264 Win Mag) 25s (25-06s and 257 Roberts) and 24s (243s)
If I ever wanted to use my 25-06 I would go with Partitions, A-Frames or Barnes TSX bullets, but loaded with such projectiles I would feel no fear about hunting elk with that gun. I just have not because I always took something else, but that's not to say I would not trust it to do the job for me. My daughter and both my grand sons have killed elk with a 257 Roberts I made form her about 40 years ago and all have been good clean kills. Just for my own comfort I would bottom out at the 243, but I would not say a good GMX or TSX bullet from my 5.56 AR15 would not work too. I just have no intention of doing it myself. I think I could, but I like my other guns too much and as an old man, I like what I like and I don't know how many more hunts I have left in me so I take the guns I enjoy the most when I go out after anything.
Last edited by szihn; 02/23/21.
