The 178's are great bullets... if you have an IMR 4895, put 42 grains of that behind them (midrange pressure load) and see if they don't shoot lights out.
Around 44 grains of Varget, or 42 to 43 grains of IMR 4064, or 42.7 grains of RL15 all should work pretty well with those 178's... that's in Winchester brass, and work up to those charges of course.
If I had some 168 AMAX's on hand, I'd trade you for the 178's... but alas, I don't.
Maybe it's a blessing in disguise, as the 178's may do great for you.
When someone is calling your shots with a spotting scope, simply due to the sloping ground it could look like you're 25 yards low, but you're really just 25 yards "short of the target" and elevation-wise you're only two or three feet low, if you see what I mean. Two or three feet of elevation drop could cause the bullets to strike ground 25 yards short of the target, depending on how the ground is sloped.
Good luck with the 178's. They're good bullets...