After talking to a few people I found out why it doesn't accept the HP rounds.
From what I was told because the original 1911s were for the service. Due to Geniva convention it's not supposed to accept HP rounds because it isn't as "humane" as a standard fmj.
Sounds about right but could be a buncha smoke.
But considering all the hoopla and the work, it's not worth it to me. Fmj's are plenty enough to do the job.
Thanks for the input!