Do you have a rifle now? If so what is it chambered in?

All of these are fine elk calibers.

.270 win or mags, 7mm-08, .308, .280 Rem., .284 Win., 30-06, any of the 7mm mags, any of the 300 mags, 8mm Rem mag., .338-06, any of the .338 mags, 35 whelen, 350 Rem mag., on up to as big as you want.

If you have any of these listed you already have a good elk rifle.