I would tend to think either would be more than sufficient with proper bullet selection.
Discusion,
What would you shoot a 85-145lb wolf with if you had a choice!
1) A faster and flatter 6mm 100-115 grain.
2) Or go for the gusto and shoot a slower .308 bullet in 135-150 grain?
Scenario you get just one shot and it may be up to 400 yards.
Note: wolves are thin skinned but you hit a shoulder blade and the bullet expands right there.
No head shots!
I would tend to think either would be more than sufficient with proper bullet selection.
"Life' is tough. It's even tougher if you're stupid." ~ John Wayne
“Under certain circumstances, urgent circumstances, desperate circumstances, profanity provides a relief denied even to prayer.” —Mark Twain
While I can't speak from first hand experience with wolves - I agree with Mr. Baker. The 6mm's do have their limitations but in this case I'd reach for my very accurate .243 and either a 95 gr SST or 95 gr BT. JMHO. :-)
I have a summer and fall to think about it. I know from experience that although canines have thin skin they are just plain tough.
My delima is this, Its going to be a one shot deal as they are spooky as hell. May take a whole week just to see one or even see tracks. I just don't want to blow it because I don't have enough gun. My fear comes from years of seeing yotes that should of been anchored, merely lay down and rest after the shot, get up; and in a blink of an eye they are gone.
Heres an 16 year old very lousy video when I thought I would get into the yote hunting video game. But I was lousy with a camera even if I had it mounted to the scope. Hahaha. Does show what I mean on how tough they are. I was shooting a Savage -22-250 Predator back then place was below a butte in New Mexico. Snuck in on this one eating on a cow carcass. He saw me but since I was on my belly for the sneak it did not run off instead it challenged me. Turn the volume up! Range was about 80 yards.
Allow me to slightly amend my earlier recommendation. If you are seeking more terminal energy to up the insurance factor, your 30-06 with a 150 gr SST will do that nicely out to some serious ranges on a wolf. Then again - as you well know - the 6mm's have the trajectory advantages and still hold more than enough to get this particular job done out to sane hunting distances. Your 22-250 experience? The .243 Win brings a lot more to the table with an 85 gr to 105 gr bullet. Again, JMHO. Wish I could go with you. You know............just in case it got ugly and I had to back you up with your 30-06..........using my 243. :-)
Were you able to recover the coyote, and what load were you shooting? If you recovered it, tell us about the bullet's path, etc.
As to cartridge choice for wolves, either of those would be just fine. You certainly won't be undergunned. Pick whichever you shoot best and have the most confidence in. Being able to plant a bullet into just the right spot is more crucial here than is the choice of .243 vs. 30-06. Like you noted, you'll probably have only one chance, so having a rifle that you are comfortable with and confident in will be the key to connecting.
400 Yards? I'd pick a caliber that can shoot a 150-168gr bullet. One and Done. You only get One Shot. Make the most of it. I shot dozens of Yotes with a 22-250 out to 250/300 yards and everyone was DRT.
400 yards, the bigger caliber. As long as you shoot both accurately. Flatter shooting doesn't mean much if you know the exact distance and either your scope settings or hold overs.
Frank
One rifle, one planet, Holland's 375
Without knowing what 6mm you plan on using- or bullet choice it's hard to give specifics..... but the .308 bullet probably wouldn't be slower if you are in the 135 grain area. In the 06 those bullets can be around 3200fps- and a lot (most) of 6mms will be below that with the bullet weights you listed. BC is a different story- but to only 400 yards may not make the difference you think. Either option is more than enough.
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