The cartridges you note will work fine at 2100 and at least the 338 LM Imp can be pushed to do 2650.
It appears from your post that you have an action with a 338 LM bolt face. As such, I'd recommend the 338 LM "Improved". Also appears that you realize that there are a bunch of 338 LM "Improved" variants. The issue will be matching the dies to the reamer. One significant advantage of going 338 LM anything is the availability of Lapua, and now Peterson, brass.
BTW, IMO the only advantage the base 338 Edge has over an improved 338 LM is that there is a much better chance that you will have a chamber-to-die match. Defensive Edge offers a die set (
http://www.defensiveedge.net/index.php/products?start=15) but they do not offer a reamer (at least it is not shown on their site)...but I suspect they will be more than happy to provide the associated PTG and/or JGS reamer number. They also have a +P version that will probably be close to matching the velocities of most 338 LM Imp variants - may use the same die set since most (all?) of the +P improvement is in the long throat.
As far as dies for a 338 LM Imp variant, I suggest you have your smith cut dies with the chambering reamer he uses - preferably a resize reamer but he probably will not have one. Newlon makes blanks -
http://www.newlonprecision.com/
Tuning is tuning. Every rifle combo is a bit different and you will need to step through the process. Lapua and Peterson brass will likely yield better brass life (over the Bertram that Defensive Edge offers - for the base 338 Edge - and the various RUM and other 338 LM offerings).
As far as shooting out barrels, that's pretty much a function of how hot you load. In that regard you will be your own worst enemy. One thing I STRONGLY recommend is as long and as stiff a barrel as you are willing to deal with. I have a .338 Allen Xpress +P and run 300 Bergers at 3244 from a 36" straight cylinder barrel. That equates to well under 1000 rounds to "shot out".
Hope the above helps. E-mail me if you want to discuss further -
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