i started a thread asking about inletting m4 and m5 bottom metal. i was building a rifle for a wsm and changed at the last minute to 308. i got a 308 barrel 20" long from broughton. my mcmillian stock on the other hand i was unable to change because it was ready really early. (this is usually a good thing) so i was asking about if i could still use the stock for 308 win. i am waiting on a reply for this on the other thread. i was wondering though since the stock was made for wsm and wyatts extended box, maybe i should just build a 300 wsm or rsaum. how would this do in a 20" barrel. it has 1:10" twist. if i was to shoot some heavier smk out of it, would this be alrigh for long range? out to maybe 1000? does anyone else shoot pretty far with 20" 300 wsm or rsaum? if so what are some loads looking like? thanks