I'm only telling you what the 35 Oehler tells me, with my barrel. Even with the bullet out to 2.950 OAL, 48 grains of 748 is at the starting point of a compressed load in FL sized, necked down .358 win cases. I was able to size down .358 with no thickening of neck brass,calculated, 55376 psi, 99.16% burn.
Hodgdon tests on their data site, shows a max of 49 grains of 748 in 24" tube getting 2665 @ 53,400 psi. And with 8508XBR, a max compressed load of 47 grains getting 2721. @ 59,000psi. both at OAL of 2.80 My results are more in line with the predictions of my Quickload program plugging in a 28" barrel and OAL of 2.950.
As I said before, with the 185 Gr. Barnes in Encore OAL of 2.950 puts bullet .050 off rifling. And, with 748, a max fill of 48.3 grains. If bullet was set to SAMMI 2.80" 44.9 gr. of 748 would be 100% fill. Seating bullet out further allowing more space in case, is allowing me to get more vel. with less pressure. And, that's what I want in a break action Encore. 2750 fps with .432 BC 185 TTSX is quite acceptable as it lines up exactly, (on paper)until I finish tests, with the BDC range hash lines on my Vortex 2-7X scope. 300 yds. is my personal range limitation for Elk in the Idaho Black timber areas I'll be hunting. Drop difference at 300 yds. between 2750 and 2800 is only 00.6". In Quickload calculations, 8508XBR appears to build more pressure faster at near max loads then 748. Still have to load more rounds for accuracy testing. During velocity tests, most groups had bullets touching at 100 yds. But, groups were in different places by 2 to 3 inches as powder increased. And, had brand new scope adjustments to contend with...And just about out of one old lot of 748,(in metal can), will have to start with new 748 lot at some point... Quickload calculates highest vel. with this combination using IMR 3031 @ 46 grains getting 2850 fps. 57407 psi & 100% burn in 28 in. I only have a little of that powder left in a very old can (20+yrs), have not been able to get any new.
Last edited by 180pilot; 07/22/13.
