I'm wanting to start a 1000 yard capable custom built, 700 action squared up, broughton, hart, shilen barrel haven't decided for sure. McMillan stock of some sort, probably jewell trigger. I at first was leaning toward the 300 win mag, but am leaning now toward the RUM, I guess mainly for the ability to push the 220+ grain over 3000. I know there are lots of other options I've read about on here as far as caliber, but I haven't really made it into wildcats yet, I'm still in the factory produced brass stage and not reformed or trimmed, necked down calibers. Maybe one day I'll advance into those. And from what I've read on here so far, the 300 RUM has a lot of potential. I'm just building a toy, nothing competitive, but something I can lay down and play with at the long range, really my first run at 1000 yard and learning the long range ballistic game. I've read about starting with something simple like a 308 and I know it would do great, but I'm more of a hit a little harder guy, and I don't want to shoot sub 200 grain and wish I had something a little heavier the whole time.
Nevertheless, I'm just keeping my ears open for an action in the meantime and was wondering about comparable calibers to start with as far as action length and boltface. I don't want to get anything that requires to much extra gunsmithing.