223 70 gr berger

Would these fit in a magpul magazine? I'm thinking the target version of these might be good and fur friendly for my ar

If you believe everything on the internet, yes

HOWEVER (conjecture follows), I would anticipate you having trouble getting them to shoot well at magazine length. The 73gr will almost certainly play better with the jump you'll have shooting a magazine length COAL. My best guess is that while they can be loaded to 2.260, they'll need to be longer to shoot optimally.

btw -- aluminum mags will give you a few more thous to play with in COAL.

edit -- also worth noting, berger has fantastic support people, just email them.
Techsupport [at] bergerbullets dot com

1.760" max case length + .471" tip to ogive length = 2.231" COAL if you seat the bullet at the ogive. So, yes, there is room enough to fit it in an AR mag with a little room to spare, .029" to be exact.