I have owned 3 of the 5 calibers mentioned and might be able to offer some feedback. While I don't own and 338-378 or a 338 Ultra mag, I have owned and 300 ultra, a 338-300 Ultra and a 338 Lapua.

I will say that in my experience the 300 ultra is not the way to go when you are comparing it to the 338/330 Ultra (AKA 338 Edge) or the 338 Lapua and especially when you are looking for a true long range caliber. I am not saying it is not a good caliber but in my opinion it is not in the same league as the Edge or Lapua when it comes to long range work.

So with that said, I would say that between the Edge and Lapua there are pros and cons to both which most have been mentioned and it really comes down to cost of components for the most part. However in my humble opinion you get what you pay for and I have found the Lapua brass to be a better choice. You can't go wrong with either one of the 338's. I chose the Lapua in the end to get the better brass to eliminate as many variables as I could.

Here is my Lapua...

[Linked Image]



Here is an example of how she performs...


[Linked Image]



Here is a link to a video with another example of how she performs...


http://www.youtube.com/watch?v=uWyOtb6ycLY



and yet another example of the Lapua's...

[Linked Image]


Here is a picture of my Edge...

[Linked Image]




The key here in my opinion is to get the best that you can and practice, practice, practice! You have narrowed it down to a couple of good choices. I would push you toward a 338 vs. a 30 cal cartridge but either way, you need to pick what you think will work best for you and practice, practice, practice. Spend your summer shooting and learning your rifles and your personal limitations before pursuing game in the field.

Good luck with your build!

Oneshot