5wire I have a 16 FCSS in .260 with a Redfield 4x12x40 scope. I have shot hogs out to 300 yds with it and I works well. I am sure the .223 will perform well out of the same rifle. If you remove the action from the stock make sure to go thru the proper re-torque sequence to put it back in. I like my system so well my son bought a 10 Precision with the same removable magazine and accustock but he got in .308 with a shorter 20" heavy barrel. You have a great setup enjoy it.