I have been using the 6.5DTI as my primary do all coyote/deer rifle the last two years. So far I have killed 9 whitetails and 6-7 coyotes, and 1 bobcat with it. The barrel on mine is 19" per my request-don't know if that is optimal but I wanted a handy length but one that would get the blast away from my ears a bit as this is a hunting rifle. I use the 85g Sierra bullets for coyotes and 100g Nosler partitions for deer(I happened to have a good supply of this bullet when I got the upper). The Sierras are a pure hammer on coyotes-a lot more noticeable whack than a .223. The 100g Noslers work well on deer-no complaints-usually a pass through but 2 stayed in the deer. Some bang flops, some short runs, some staggers and falls. Typical from most any other caliber that I have used. You will find that bullets heavier than 100g use up powder space in the case. You are limited to the magazine length of about 2.300 with a PRI mag-which generally allows the longest oal of any of the 6.8mags. Although the new CProduct Defence mags will pretty much allow 2.300 also, are reliable, and are a lot less expensive than the PRIs(which are excellent mags). I am confident my coyote loads would be instant death for a deer hit in the chest but haven't used a 'coyote specific' load on a deer yet. Thats my take-I really really like my 6.5-it turned out to be all I wanted in a mythical all purpose TN predator and whitetail rifle. Do you have your 6.5 in hand or on order? Mine is the 1st one that Mike built.