We have a tikka 223 and boxes of tmks. She has killed a deer with this combo and she shoots it very well. She is recoil shy. This combo has been very positive for her.
Imagine I'm still a licensed guide whom you're considering booking a trip with and you volunteer the information contained in the quote above and then ask me what rifle your daughter should bring.
My answer would be "Bring the Tikka in .223 Remington that she shoots very well and already has confidence in from filling tags with it."
I'd give that answer because I've been involved in the post-mortem of literally thousands of wild pigs. Assuming the .223 Remington is used in conjunction with bullets proven on hooved game, like the 77 grain TMK, you won't be able to distinguish the wound channels it makes from those made by a .250-3000 Savage, .257 Roberts, .243 Winchester, 6mm Remington, 7-30 Waters from a Contender, or a .30-30 shooting 160 grain FTX bullets over a full dose of "LVR" powder.
Shoot a pig of around 300 pounds on the hoof through the heart with a .223 Remington topped with the 77 grain TMK and it will die just as dead, just as fast, as if you'd have shot it with a 7mm-08 in the same place.
Going up .020" in shank diameter and 23 grains in bullet weight isn't going to result in a real-world difference that an animal will notice. I know this from my personal hunting, where I used the .223 Remington on black-tail deer to fill 22 consecutive California A-zone tags and used a .250-3000 Savage to fill 21 mule deer tags, 3 pronghorn tags, 2 caribou tags, and 1 bull elk tag. If I would have had the .224" component bullet selection in 1985 that I have in the here and now, I wouldn't have felt a need to own a .250 Savage beyond thinking it was cool from reading too many books by Roy Chapman Andrews.
Here's what the terminal ballistics of my 100 grain Nosler Partition load looked like when shot out of the 20" barrel of my Ruger M-77 RL Ultralight (Distance / velocity / energy):
M / 2620 / 1524
100 / 2352 / 1229
200 / 2100 / 980
300 / 1865 / 772
Here's what my 77 grain TMK 5.56 NATO load does out of the 20" barrel of my AR-15:
M / 2854 / 1393
100 / 2636 / 1188
200 / 2428 / 1008
300 / 2229 / 850
In terms of terminal ballistics, there's not enough difference twixt the twain for any hooved animal to live on.
I have to say I’m a little apprehensive having her shoot a moose with it.
Don't be. Whacking big game animals with ".22 Caliber" centerfire rifles isn't some new thing that only people on rokslide have done. The .22 Savage High Power was introduced in 1912 as a cartridge suitable for all North American hooved game. The .250-3000 Savage is and always was every bit the pipsqueak round that the .223 Remington was and is. Roy Chapman Andrews killed things far bigger than moose with Savage 1899 and 1920 model rifles in .250-3000 Savage and praised it as an effective and efficient killer. And Andrews sang that praise based on the original 87 grain load, which charts out like this:
M / 3000 / 1739
100 / 2680 / 1388
200 / 2382 / 1096
300 / 2103 / 855
Those are the terminal ballistics that Roy Chapman Andrews worked with when hunting moose in Canada and Alaska.
I think a well placed broadside shot would go well.
If Andrews could "one-shot drop" moose on the equivalent of modern 5.56 NATO terminal ballistics, your daughter will be able to, as well. He did broadside heart-shots with surgical precision. A modern 77 grain TMK .223 Remington / 5.56 NATO load is even better for shooting with surgical precision than what Chapman used, because it shoots flatter and has significantly less wind-drift. Terminal effect is better, too, by benefit of a sectional density of .219 verses .188 for the ammo Chapman used.
