I have just reviewed all these pages as I am working up loads with Norma 180 gr HP's and Speer 180 gr SP's using H4350.
Out of 7 manuals ( old and new) I could find none that ran over 57 gr of H4350 or IMR 4350 using any 180 gr bullets. Some guys must really like living on the edge as those 60 gr loads must be something.
From 54 gr to 56 grians in 1/2 gr increments,the sweet spot with my Pre 64 Model 70 FWT in .06, 55'ish grains looks promising.Book value on velocity is in the 2760fps realm.These were set about .020 off the lands They hover around 1" at 100 yards which is about the best this gun will do.
Loads satrted out giving 2&1/2 " groups,shrunk downto 1" and thenopednbak up to a little over 2" as I approached 56 gr.
I was out two days ago,but could not chrony them.
I completed loading today of another batch in 1/4 grain increments around the 55 grain load.
With 180 gr Sierra GK,my accuracy load has always been 57&1/2 gr of H4831,but it did good if it broke 2600fps
