I'm biased. My favorite rifle to compete with, shoot recreationally, and hunt with is the AR-15 A4 style of rifle in good, old-fashioned 5.56 NATO.
For me, the "what rifle should I start my child off with" is a no-brainer with one correct answer, and it is an AR-15 type of rifle in the "optics ready carbine" style, chambered in 5.56 NATO, and assembled to have a carry weight, sans optic, of 6 to 6.5 pounds.
The OP's daughters might not know it yet, but they agree with me, too. They would a rarity among young ladies if they didn't, in my experience.
How do I know?
When my own daughter expressed a desire to shoot and hunt with a center-fire rifle and had demonstrated she was emotionally mature and responsible enough to handle one, I took her to a local WMA range and let her try my Ruger M-77 RL Ultralight in .250 Savage and my DPMS Oracle in 5.56 NATO. After 10 shots from bench and rest with each, I laid out my shooting mat and had her shoot from standing, sitting, and prone, firing ten shots from each position, with both rifles. After completing this course of fire, I asked her which she liked better.
The AR-15 was the clear winner.
While we were there, there were four other families at the range that day, and two of them took note of what my daughter and I were doing and expressed a wish that they could do the same thing for their daughters. I had four other little girls do the same thing my daughter did.
They all preferred the AR-15, as well.
It isn't an "age thing," either. My step-daughter was 28 when she first came to the U.S.A. to visit. I bought her a non-resident hunting license so she could legally use the WMA range when she got here and, as she was coming on a visa waiver with an Italian passport, she could legally possess and use firearms and ammo here. I did the same thing with her that I did for my biological daughter and my older step-daughter also picked the AR-15 as being more fun to use because it was easier to shot accurately.
I've literally had dozens of pre-teens and teens from 9 to 13 "take the pipsqueak deer rifle challenge" and every single one of them preferred the AR-15 over my Ruger M-77 Ultralight in .250 Savage.
When I bought that Ruger M-77 in 1985, I bought it wanting it to act like a .250 Savage, so I always ran SAAMI pressure handloads in it, which is 45,000 C.U.P. or around 50,000 PSI, while I load my 5.56 NATO at or near full 62,000 P.S.I. pressure. In terms of terminal ballistics and felt recoil, my .250 Savage had a lot more in common with 5.56 NATO than .243 Winchester, so it isn't the "apples to oranges" comparison one might think.
Both the DPMS Oracle I had and the Ruger M-77 RL weighed around 6.5 pounds, sans scope and mounts. I used Leupold Vari-XII c 2-7X scopes on both, too.
Both were also similar in mechanical accuracy, too, being one-minute rifles.
The kids all like the AR better because it fits them better, they feel like they have more control over it, and it is easier to shoot accurately away from a bench and rest.
In other words, kids prefer the AR platform for exact same reason that I do.
In closing, after buying that .250 Savage I had back in 1985, I went on to tag 21 mule deer, 3 pronghorn, 2 caribou, 1 bull elk, and only God knows how many feral pigs with it. That is relevant because the 77 grain TMK 5.56 NATO load I use now shoots flatter, exhibits less wind-drift, and delivers more kinetic energy at the 300 yard line, with higher impact velocity at 300 yards generally resulting in slightly superior wound channel volume. I had used the .223 Remington since 1984 to fill 22 consecutive California A-Zone tags on blacktail deer, which were pint-sized compared to the mule deer I hunted in California, Utah, Colorado, and New Mexico. I didn't have the .224" bullets back then that I have now, which allow the 5.56 NATO to deliver the same terminal performance as the .250 Savage out to 300 yards. If I did, I would have used the .223 Remington on mule deer with complete confidence, just as I do now.
Last season, I shot a mule deer though the heart at 268 yards with my AR-15. The 77 gain TMK macerated the heart muscle on a buck that weighed 195 pounds with the guts out and the hide off. The Ruger No.1 B in .300 Weatherby Magnum that I used to have would not have killed that deer any deader than my AR 15 rendered it.
Give a kid a choice between a very light recoiling bolt-action or a virtually non-recoiling AR-15, and the latter will get picked as more fun and easier to use, virtually every time.
