2003 LG winner in Iowa was a self-built ( not me, now) stocker who used a vented 2 pc aluminum barrel block. That design is now under production review by Dave Kiff at Pacific Tool And Gauge, www.pacifictoolandgauge.com.
The mounting means are many including bedding the lower half allowing for fast action and or barrel changes. I have one on a tac carry rifle. These will adapt nicely to the Joel Russo modified A-5L stock shown elsewhere on this forum. Overbore