Rem. 700 300 ultra mag conversion


Mar 14, 2008
I have the chance to trade a benelli pump shotgun for a Left-Handed Remington 700 BDL 300 RUM sporter. Good deal??

If I do get to go through with the trade, I think I am going to build a long range set-up off of this action. I am trying to decide what I caliber I want to change to since I don't really want a .300 RUM with a sporter weight barrel or any weight barrel. It just costs to much to shoot and the cases have a short life.

Which long range calibers can you build on this action that would be the most economical (as far as ammo/reloading) and performance wise?

What common calibers have the same size bolt face as the 300 RUM?

I was thinking maybe a 300 win mag or 7mm Mag. I have a friend with a lathe and milling machine that I am going to use for the build. He has started doing a little custom work on the side and from what I can tell he does a good job (especially fluting and threading). All I will have to do is supply the parts, and he will do the rest for free just to show his work off.
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Sounds like a very fair deal, and both the 7mm Rem Mag and 300 Win Mag have identical case head diameters to the 300 RUM.

I'd at least shoot the 300 RUM first myself, just in case it's a tack driver straight from the factory...
I plan to shoot it first since I have a friend with a sendero in 300RUM. If it is a tack driver I may leave it alone or just restock it as I think I would want a little more weight. (I am right hand/ left eye dominant and I have been teaching myself to shoot lefty. This rifle may just hurt a little)

I had a 700 ADL in 30'06 when I was in highschool that would shoot cheap rem. core-locks under an inch. I would love if this 300 RUM BDL did that. If it does I would love to see my buddy's face.
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