Hi Cody, that would be .223/5.56. For home defense these will work budsgunshop.com/product_info.php/products_id/75970/pmc+x-tac+5.56+nato+55gr+full+metal+jacket+boat-tai+20rd+box ,
Best mag size is 30 rounds, you never know how many rounds you will need to defend yourself.
Stay safe & have a great day!

Hi Cody and welcome. 5.56/.223 with 60rd quad stack German Magazine will be the best home defense setup. Magazine : budsgunshop.com/product_info.php/products_id/132070/ati+atim556s60wmle+s60+schmeisser+223+rem5.56+nato+american+tactical+imports+schmeisser+s60+60rd+black+polymer+detachable+magaz ----------------------------- Ammunition : - budsgunshop.com/product_info.php/products_id/1822/hornady+american+gunner+.223+remington+55gr+hp+50rds ---------------------- Cheers, stay safe and enjoy!

Yup, AR chambered for .223/5.56 is the most common used in those instances. Ed is right, takes up to 30 round magazines & the use of 50 round drums as well!