My .260 feeds like a champ, with nary an issue.
Mag box is 3"??
Little shy of that, about 2.95"... I'm running 123 Scenars at 2.865" and 123 Amax at 2.90".... Same BTO.
I'm actually not disappointed in the stock. I know a lot of people don't care for them but mine seems pretty solid and it's comfortable to shoot with from the prone.
Travis
The only thing I did to mine was sand the moulding lines off, and took the two spacers out. With SS in lows it sets-up very nicely, and recoil is very manageable, even for new shooters.
Three different shooters at 600.... this was rounds #11-13 outta my CTR....
"Load Development".... Laffin....