I'll have to check my notes reference our recent barrier/gelatin tests for specifics but I'll say the monolithic bullets had nearly 100% weight retention and "excessive" penetration (per the FBI standards) through the glass types we tested them against: tempered, double-paned residential; automobile windshield and laminated commercial glass (similar construction to auto windshields). In the past we've tested the GMX and Barnes TSX loading for accuracy but couldn't get either to meet our expectations with our duty rifles (AI AE Mk-II). Typically I've seen the solid bullets display flattened tips after passing through glass, which limits their expansion potential. Our recent glass test included Ruag's Swiss-P Tactical, a flat-tipped copper solid bullet, after we had tested it for accuracy, which is consistently sub-MOA at 100yds. Although the Ruag is an expensive bullet, it is now our new barrier loading, after our guns started to dislike more recent lots of the 180gr Accubond...
Contrast that with my experience with federal's loading of the Barnes' 165gr TSX bullet out of a tired, worn Rem700 for hunting which is consistently sub-MOA. The one bullet I've managed to recover over the years expanded perfectly like an advertisement and weighed-in with 100% weight retention after passing through the chest of a muscular mule deer buck and breaking several ribs enroute to the rear of the body cavity. I hand-load 180gr TSXs in 30-06 for a 1950s vintage Model 70 and can get just under sub-MOA groups with that combination.
I would definitely recommend a monolithic bullet for hunting and if you can find one that shoots well from the duty rifle, as a barrier load as well. Just be aware of the increased potential for over penetration that may be part of that equation.
