My experience has been that two-syllable names are easier to use, especially in the field. I know that sounds silly but try calling out each name in a loud, firm voice like you would use in the field. See if Ruger isn’t easier to say than the others. Just be sure you actually have the pup with you or that no one else is around!!
If you wanted to keep an archery theme, you could always go with Mathew! (With all due deference to Mr. McPherson!)