We have some IPDS printer files that create bar codes and we utilize the CHRSIZ keywork. However, it seems like going from v6r1 to v7r2, when we recompile them, the CHRSIZ doesn't really work like it used to. Does anyone know of any changes or how we might need to recompile these?

I'd start here:

https://www.ibm.com/support/knowledgecenter/ssw_ibm_i_72/rzakd/rzakdmstptchrsi.htm

If that doesn't have your information I'd either ask on the Midrange.com mailing list (midrange-l to be specific) or contact IBM support.