Yes, feed rails on a 223 are narrower than on a standard bolt face short action. I polished up and removed a bit from a 223 receiver for a 6x47L project as it was the only short SS I had at the time. It fed without issues about 80%. Finally bought 'the correct' receiver for that size cartridge and it works 100%. Barreled the prior 223 receiver to 223AI and it feeds near perfect. Have had issues before with 223AI feeding trouble free with a 700.
