Ok boys lets grow up a little bit and tone down the names and swearing as well as other folks that this type language offends.
The guy that origionated this post hasen't even replied back since the first page at what time he responded that he wuld be using a 300 so arguing this point to convience they fella is redundent.
If you talking about factory loaded ammo then it need to be an unbiased test ,no shopping around for hotter loads no short barrels to long barrels and so on , just an apples to apples compairison. Here is some info from Federals web site compairing the 7WSM to the 300WSM with both lighter weight deer bullets and heavier big game bullets in the same make
7mmWSM , 24" test barrel
140gr Nosler Balistic tip launched at 3310fps
15.2" wind drift at 500yds in 10mph breeze
30.6" drop at 500yds with a 200yd zero
1705 ftlbs energy at 500yds
160gr Nosler Accubond launched at 3120fps
14.7" wind drift at 500yds in 10mph breeze
33.8" drop at 500yds with a 200yd zero
1826ftlbs energy at 500yds
300 WSM , 24" test barrel
150gr Nosler Ballistic tip launched at 3200fps
18" wind drift at 500yds in 10mph breeze
34.5" drop at 500yds with a 200yd zero
1558ftlbs energy at 500yds
180gr Nosler Accubond launched at 2960fps
16.8" wind drift at 500yds in 10mph breeze
38.7" drop at 500yds with a 200yd zero
1763ftlbs energy at 500yds.
So everybody can see that the 7mmWSM shoots flatter , drifts less in the wind and even hits harder at long rantge than any compairable loads out of the 300WSM , these are two case of same shape and very very close to same case capacity so this shows that even at 500yds the BC is a big factor and very evident , I can assure you that the gap only grows as the range increases and all this with less recoil? inda makes you wnder whay anybody would choose the 300WSM to begin with.
I'm not choosing sides as I don't own either and the only reason I would would to build a light weight gun on a short action , I don't believe that the belt on the old mags has any differancr in the accuracy , and if I were going to build a gun on either the 7mm Rem mag or 300 win mag I would choose the 300 win mag as I feel its a little bit more versitile with the brad range of bullets and Lapua offers bras for it.