Update on the elk mount and I finally got around to bullet weight retention.
Received a call from Gary at A1 Taxidermy in B'ham last weekend that the elk mount is ready to go. Great turn around time I'd say from early Nov to mid Feb at 3 months. Picking it up Friday so will post some photos once I get it installed. Wife is thrilled and I cannot wait to see it! Perfect timing as my Bday is coming up in Feb and hers is early March.
As far as bullet performance, it killed the elk for sure, but like I'd mentioned earlier piss-poor expansion granted it wasn't a super hot load. Specs are 30-06 56.00 grn RL-19 in Remington once fired brass and Winchester standard large rifle primers going ~2600 fps out of a 22" barrel. They shot accurate, recoil wasn't terrible for the wife, and I was able to use up a bunch of components on hand (plus it worked). Regardless I'll likely go back to the 62 grn RL-22 compressed load and Nosler Partitions my ol' man used to run.
Scale is in grams but grain conversions are added. It's 98% retention weight on the main projectile. If I include the small separated tip/jacket portion it actually jumps up to 103% due to tissue I couldn't get out:
Grams Grain Retention %
Nominal 11.69 180.404
Slug 11.41 176.083 97.60%
Slug & Shell 12.00 185.188 102.65%