Castman,
This one has been "sitting" for a while. Nice of you to "pick it up." Your post appears to be a combination of honest well intended advice combined with some skepticism, let me explain where I'm trying to go with things.
Why do you need "2000 ftlbs at 600 yrds"?
This rifle would be for both target and selected hunting situations. I currently hunt elk with rifles that deliver 4,000 to 6,000 pounds at the muzzle for game at ranges 250 yards or so --- I just kind of like that kind of power, not likely I will ever be accused of being undergunned; however, I recognize that long range shooting "weakens" all rifles to a mere shadow of their former "200 yard selves". At long range I want a goodly amount of "thump" left over after the long trip.
You say you want a factory gun but you also want it to be heavy, factory guns dont come heavy.
That is an easy one. Some are heavier than others for example 700 Remington Police models in 300RUM with bull barrels. Weight I would add to the degree necessary if I deem the rifle not heavy enough, heavy was not a "from the factory" requirement. I currently have a M70 375HH though that weighs 12 pounds with scope, ammo, sling --- IMHO that is pretty heavy for a "stock" unaltered rifle.
Since you want a factory gun you are limited to a 30 cal with 220gr bullets (240s will require a faster twist) or a 338 cal with 250gr bullets (300s will require a faster twist).
We agree some here but not in entirely:
7mmSTW 160 gr. TSX 2180 pounds at 600 yards (2477 fps). [TKO=16] Recoil 19 lb/9 fps.
300 RUM 180 gr. TSX 2494 pounds at 600 yards (2498 fps). [TKO=20] Recoil 27 lb/11 fps.
338 Lapua 210gr. TSX 2702 pounds at 600 yards (2407 fps). [TKO=24] Recoil 34 lb/13 fps.
(May have to substitute the 338RUM since Lapua is kinda scarce, numbers are a little less though.)
Ballistically I find the 220/240gr 308s and the 250 gr 338s to tend to "fall out of the sky" too rapidly plus most "factory rifles" will have twist rates oriented to bullet weights closer to the mainstream.
Nice recommendation of the 700 Sendero, I've looked at them. However I would probably go with cartridges mentioned above which are saltier than the venerable 300WinMag. Your mention of scope would be quite nice.
I wouldnt worry about getting sloped bases if your only shooting 600 yards.
Well, there comes the rub --- this kind of rifle is already out of the mainstream (the way I'd set it up) and thus a "specialty rifle" --- within the realm of its specialty, i.e. long range I want it to where if I want to go out to the 1000 yard range and play that it is just a matter of consulting the charts and cranking in the additional MOA's into the turrets, use of the ramp assures I won't run out of elevation adjustment in order to "hold dead on" the target.
It is a project that is "on the drawing board" and I don't know a ton about long range shooting. Now that my "blue print" is a bit more available, any continued critique/observations are welcome.
Thanks,
EKM