First time putzing with cast boolits for a bottle neck cartridge and am on the lower edge of the learning curve.
Mold is a Lee LH 312-160 GC mold that LEE recently had on closeout for $15 so I bought it just to play with and learn. So I don't need to be jumping through any elaborate hoops to make it work. It's only near purpose in life will be paper punching at 100/200 yards.
The rifle is a Savage 110 in 308 WIN with a Criterion 1:10, 24" SS barrel. Pound cast of throat/barrel MICed at: throat- .31045", lands- .3082".
PC'd and sized boolits with an NOE B310 sizer bushing MIC at .3106" on the GC. The drive band above the GC is .3101" (.0004" GC spring back??)
COAL to just touching the lands is 2.595". At this length the GC is below the neck and crimp/lube groove is inside the neck. Seated to 2.665" even with the first groove and the GC mostly/nearly even with the bottom of the neck is giving me a jamb of .070".
The bolt closes with out anymore than normal resistance. Is a jamb of .070" too much?
Test loads will be with either Unique or IMR4227 (only powders on hand that I can find data for). Any recommendations for one of these over the other?
The first pic shows the seated lengths side by side with bullet lying beside where GC would be just barely inside the neck. The second pic shows the pound cast slug and the jamb loaded bullet. The red dot is just to help identify the location of the jambed land groove.