I wanted to build one some time back, I did a spot of research and found several set backs. From what I read it is unfeasable because the 115 and 117 tubbs don't appear to go over 3300. Now this is just my research not actual testing. At 3300 there is little gain over a larger bore with a similar bc bullet. I think the smaller bergers would hold together better but at a lower bc. I am opting towards a 6x284 since most of the bullets available with high bc's can only be pushed so fast. You could remedy that with a barnes solid or and really drive them out there fast, but you loose bc.
If i remember correctly the fella that had one was using 85 barnes at somewhere near 3850 with a 29 inch barrel if memor serves me correctly.
If you could crank the tubb 117's out in the 35-3600 fps you could really reach out on the coyotes. Barrel life is a performance sacrifice, its just a fact of life.