I have an older SR-25 with solid hand guard and 24" unthreaded barrel. I'm thinking about upgrading the hand guard to slotted rail like the Troy or KAC URX. I want to shorten the barrel to 16" - 18" and thread to accept my suppressor. Am I messing up the value or accuracy of this weapon? It has less than 50 rnds through it and is .5 moa but it is long and heavy so I rarely shoot it.