Re: 270 win for elk?
270 win will work very well on elk, I have shot several bulls with mine. I use run of the mill Hornady 150 gr SP bullets. Keep in mind that these bullts are not bone crunchers but a well placed bullet just behind the shoulder will have a bull down in no time (none of mine have gone more than 100 yds). If you want something that will stay together a little better try Barnes TSX 150 gr. I shot a bull last year and managed to recover one of the bullets and was pleased to see that it performed eactly as advertised... expanded to twice the original diameter, approx 100% weight retention. I guess that my choices for bullets on elk with the 270 would be Hornady Interbonds, Barnes TSX, Nosler Accubond, TBBC or something to that effect, and not neccesarily in that order.
This year was my first year with my 300 RUM and I was very pleased with its performance as well with a 230 yd bang flop with a 210 gr Berger.
Whichever he is most comfortable with 270 or 300 RUM either will work well. Hope this helps