If still available, I could definitely take the .223 boxes off your hands and put them to good use. Just let me know and I will pick-up at your convenience!
Scott
Sorry, TK5o, I'm afraid I am not knowledgeable enough to say. I personally would be hesitant to try it, but you may want to ask a gunsmith if it is possible.
Heckler & Kock MR762A1 LRP (Long Range Package II)
Contact Scott by PM
$5,950 (MSRP $6,899)
LNIB, never fired. Go to https://hk-usa.com/hk-models/mr762a1lrp/ for complete description. But in summary:
"MR762, 7.62mm Long Rifle Package II (LRP II), 7.62 mm Semi‐auto MR Rifle complete...