Most of the magnums are going to hold 3+1 and standard cartridges will hold 4+1.

Elk are definetly tougher than deer but by no means are bullet proof. I have taken enough with the standard ole .270 Winchester to know that one bullet is all it takes. If you need a second shot it isn't the guns or the bullets fault. Having said that, I would still shoot again if he is still offering another shot regardless of which cartridge i was shooting.

Any of the WSM's are excelent elk medicine as are the regular magnums and standard cartridges in the same calibers.

Since you will obviously see some long range shooting in TexasI would opt for the magnum versions of the .270 or the 7mm's. Not that the standard cartridges wouldn't have plenty enough energy at extended distances but the flatter shooting magnum would be a benefit at 400+ yards.

AS far as the guns go you could get a real shooter or one that won't hold a group to save your life with any of them. Remember that they are all "production" guns and with all mass produced items a bad one gets out every so often. Most likely you will get a gun that will shoot about 1.5" at 100 yards with most ammo you feed it.

Ruger, Remington, Browning, Howa (Weatherby vanguard), Savage, Tikka and a host of others are vry good rifles that will last you a lifetime. Hold and shoulder as many as possible and choose one that feels best to you in one of the cartridges listed in this thread.