I guess one of the points of differential here is what defines long range on big game. I have a good friend who posts here occasionally who can, and does, kill cleanly out past 600 yards but I limit myself to 500 yards and in. I consider shots of 300-500 yards long range. I am not yet a good enough game shot and wind doper etc. to be confident of clean kills beyond that so to me a rifle that shoots really flat out to that range and carries enough oomph to do 'em in when it gets there is a really cool set up. If I WAS going to get into really looooooong range deer shooting I would probably go with the 6.5STW that you mention or a 7RUM. Might have kept my 300RUM.
The point, I believe, is that the speeds at which we can push the 130TSX from big 30's enable us to sight in and hold similarly to what I do with my 257WBY and hold on hair much further out than would be possible with the previously available big game bullets in 30 caliber. That is an appreciable change of the equation. And a deer is not so hard to kill that a 130gr TSX, which will retain 100% of its original weight or very nearly so even AFTER impact will not get the job done with room to spare. I am pretty sure no one here is suggesting 500 yard and beyond shots on Elk or black bear with this bullet. For that I have my 340 Tyrannosaur and our poster probably can buy some PMC or Federal ammo with 180gr TSX's for that job.
This is fun......
It is fun. It is also the exercise I went through when deciding in what to chamber the custom rifle I�m building. The end result was a 6.5mm-06 pushing 130g Scirocco II�s (BC .571) to 3151fps, or the AI version a bit faster.
But I also have a .300 Win Mag and took a hard look at the 130g TTSX. I�m already using the 168g TTSX (BC .470) in my .308 Win and .30-06�s, and compared the 130g TTSX (BC .350) to that. Using Nosler load data at 3290fps for the 168g and Federal�s 3500fps for the 130g yields some interesting results.
When zeroing my rifles I determine the Maximum Rise I am willing to put up with and zero for Maximum Point Blank Range (MPBR) accordingly. (For MPBR calculations, Maximum Rise = Maximum Drop, so Target Diameter = 2x Maximum Rise.) I use a 3� Maximum Rise figure so for whatever rifle/load I am using MPBR defines the range at which the bullet path is never more than 3� above or below LOS.
Comparing the 130g and 168g TTSX:
130g .308� TTSX, .350 BC, 3500fps, recoil 27.6 foot-pounds (84.0g powder, 8.3lb rifle/scope)
284yds = Zero
332yds = MPBR
500yds = -23.7�, 1411fpe
600yds = -45.2�, 1148fpe
700yds = -75.4�, 925fpe
165g .308� TTSX, .470 BC, 3290fps, recoil 32.6 foot-pounds (79.0g powder, 8.3lb rifle/scope)
277yds = Zero
325yds = MPBR
500yds = -24.2�, 2002fpe
600yds = -45.0�, 1745�
700yds = -72.9�, 1479fpe
If we look at the 6.5mm-06 with a 130g Scirocco II:
130g 6.5mm Scirocco II, BC .571, 3151fps, recoil (54.0g powder, 8.3lb rifle/scope)
270yds = Zero
318yds = MPBR
500yds = -35.1�, 1629fpe
600yds = -46.4�, 1443fpe
700yds = -74.3�, 1274fpe
So, other than less recoil, the 130g TTSX in a .300 Win Mag offers no real advantage over the 168g TTSX. When zeroed for Max Rise of 3� the point of Max Rise, Zero and MPBR are slightly different, but the 168g delivers significantly more energy and shoots, within 7 yards, just as flat at MPBR distances. Beyond 535 yards the 168g bullet shoots flatter. One could easily conclude that any trajectory advantage of the 130g TTSX only occurs between 325 and 535 yards.
The 6.5mm-06 130g Scirocco shoots flatter at 700 yards than does the .300 Win Mag 130g TTSX and wins the energy race much sooner.
Nothing wrong with the 130g TTSX, but I would use it at slower speeds (less powder) for reduced recoil loads.