I just measured the shanks on the bullets I cast with the exact same WW lead batch from my Lyman 311284. (an awesome bullet), and it fits good.



The shank is : .287

The bands are: .309



So I don't think it's a case of my lead not filling out. I still may be doing something wrong, but I don't know what..

My dial calipers read on the I.D. of the mold shank cavity:



Lee C-309-150 .278



Lee C-452-300-RF .422



I'm learning how to read my micrometer (as well as us my metal lathe) so I haven't totally got it figured out yet. The dial cal measurements abouve are rounded to the nearest .001 of an inch.



Either way, these boolits are loose, and those measurements are swimmin' inside the .30 cal, and.45 cal gas checks. The .30 being the worst of the 2.



Interestingly, the 309-150 bullets cast at .310 on the bands.



The gas checks are Hornady. Hornady has been making all brands of gas checks for some time.



What is the the Fat-30 snap fit dimention? I couldn't find it on the diagram, but it may there. Where can I find the ID of Hornady gas checks?