300wm, berger 215s, Ferderal 215m...looking for help in tuning
Have run a charge weight ladder, found a node (76.5-77.5) at .020 jump.
Loaded up 77gr and did seating depth from .010 - .040...went with. 010, but .030 look ok too. About .4-.5 MOA at 300 yards between the two. .020 was .75 MOA.
Went back, loaded up groups at 76.8, 77, 77.2 and seated at .010....groups sucked, .75 at best (77 was spot on horizontally, but string out to .75 moa in the vertical indoors at 100 yards.
I'm questioning my neck tension.
Loaded round is .335, (so .0135 necks) I measure them at about 013.
I use a reddding bushing die (no expander ball) to compress down to .331 and expand out with a .306 mandrel. With springback I have what. 0025 neck tension?
I have a .332 bushing, a .331 bushing and expander mandrels in .3055, .306, .307
Not sure which combo to try...reading some 300wm's like a little more tension?
Suggestions on what to load next? Should try closer to the lands at .005 jump next or try another combo of neck tension? Maybe go with the .307 mandrel for just over .0015 tension after springback?
Seems from reading the forums, alot of rifles typically shoot lower ES with lower neck.
Have run a charge weight ladder, found a node (76.5-77.5) at .020 jump.
Loaded up 77gr and did seating depth from .010 - .040...went with. 010, but .030 look ok too. About .4-.5 MOA at 300 yards between the two. .020 was .75 MOA.
Went back, loaded up groups at 76.8, 77, 77.2 and seated at .010....groups sucked, .75 at best (77 was spot on horizontally, but string out to .75 moa in the vertical indoors at 100 yards.
I'm questioning my neck tension.
Loaded round is .335, (so .0135 necks) I measure them at about 013.
I use a reddding bushing die (no expander ball) to compress down to .331 and expand out with a .306 mandrel. With springback I have what. 0025 neck tension?
I have a .332 bushing, a .331 bushing and expander mandrels in .3055, .306, .307
Not sure which combo to try...reading some 300wm's like a little more tension?
Suggestions on what to load next? Should try closer to the lands at .005 jump next or try another combo of neck tension? Maybe go with the .307 mandrel for just over .0015 tension after springback?
Seems from reading the forums, alot of rifles typically shoot lower ES with lower neck.
Last edited: