The 257 Hawk gets a max of 3890 with a 75 and Fred says: "75gr. 257 Hawk load above was tested in a Ruger #1, 26" barrel, 15 shots averaged, probably a little too hot for a bolt action."
You Ackely ballistics are almost as inventive as old P.O. himself!
A contemporary quote:"The typical Ackley Improved case gives a modest increase in velocity over the parent case - as long as both are loaded to the same pressures. All one has to do is look at modern tested loading data to verify this - the latest Nosler manual has a number of Ackley cartridges, and the average increase in velocity is on the order of 100 fps. This is simple ballistic fact, not clouded by the rantings and hype of guys trying to sell a product. There is just not enough increase in the case capacity to make a big difference in velocity."
A 257 WB gets 3825 w/an 87 (and free bore) but you are whupping that with a smaller case? It's gonna hurt pulling that bolt outa your head if you keep running 90k psi loads!
