If the bonding process/technology on these is similar to ATK’s ‘Trophy Bonded’ pills, then that may be a reason for reports of them being less accurate than other rounds.
At certain points, the Trophy Bonded projos have had special reloading notes in various manuals or been restricted as reloading components, and the 62gr TBBC LE223T (rifle load for DEA and others) has been reported as less accurate than other common duty loads. FWIW its mechanical accuracy is still better than many of the folks behind the trigger, and at expected ranges both the Winchester and ATK bonded JSP 5.56/.223 cartridges meet or exceed most typical law enforcement ‘patrol rifle’ accuracy standards.
Variations in jacket thickness, projectile shape, etc., can make many JSP rifle loads less accurate than a competing JHP, FMJ, etc.
I’ll dig around and see what I can find on the crimp.