The very first thing that must be said is, a cast
BULLET 
shooter NEVER has enough bullet molds! There is alway a mold to buy and try out. In 30 caliber, the list is never ending. That mold that you DON'T have is the one that WILL produce that one hole group that you haven't shot yet!!!!!
That said, there are only a few people in the world that have tapered bullets for BSing in 30 cal. But, the saving grace is a good bore riding bullet. My NEI 311 169 PB (190 gr) will shoot with any of my Ron Long tapered bullets in calmer conditions.
Unless you plan to shoot in competion, your 311299 will work with the GC installed. You will just need to cast it in a softer alloy like 20/1 lead/tin. Make sure that the bore riding section, still makes contact with the lands. At least .0005 to .001 larger than the lands. Both the bands and the nose will be smaller with 20/1.
If you use that bullet, BS it until the lands show, right up to the GC, you can even let the lands just mark the GC but, no further.
To make a simple, adjustable plugged case, BSer, get a piece of 5/16 brass rod, have someone face it off in a lathe at 2" long and then have them drill and tap it to 8x32, about a 1/2" deep. Get a 8x32 socket head cap screw, run it in all the way and start measuring the engraving on the bullet, backing it out until it comes in at the above setting. When you get the setting right, meaure the length of it. Then lock tight the screw and re-install it to that length.
You can use your best powder charge from fix loading to start and then add .5 to 1 gr more to compensate for the increased case volume as a result of BSing. The extra powder may or may not, effect accuracy but, you should have lower velocity with the same powder charge with BSing.
I hope that helps,
Frank