Been reloading for my 700sps bolt action now for a while with great success. I just picked up a CMMG AR 15 with 1:7 twist, 16 in barrel and was wondering how much different they both are to reload using the same components. I know COL will be a factor. Could I reload the once fired brass from my 700 using the lee collet neck die or will I have to full length size? Also after spitting out about 130 factory rounds in my new AR, I found all the brass had a ding towards the neck of the case in the same spot of each round, will this brass with the dings be safe to reload?