|Neat cut-away pics first page!!!!|
Thanks,I use those to set my OAL when it's possible,the case with the small slit in the neck is just enough to hold tension on the bullet but allow it to move inside the case necks. I insert the bullet and slowly close the bolt and lock it in place then slowly remove the cartridge and measure the OAL and go from there. This particular Mosin rifle has a deep throat so I can't seat the bullets out as far as I would like but it seems to shoot well where I ended up at.
The second cartridge is cut much deeper down to side to allow me to see if the dacron filler is sufficient enough to take up the space between the powder charge and the base of the bullet. When I use it which isn't that often I like to make sure I use just enough and not have it be packed.
Currently though I use H-4895 instead of IMR-4895 because I can reduce it by 60% from the max load with no filler needed. My current load which is getting me around 1700 fps. with 33.0 grs. is at about 78% density. My next test loads will get me up to about 85% at 36.0 grs.which should get me in the accuracy / velocity / RMP range with my 185 gr. bullet. We will see.