Those mags aren't the only ones that are a PITA to load to the stated capacity.
My M+P factory mags, even my G21 13rd. mags are a cram at rd. 13. Some of my Wilson 1911 8rd. mags are really a push, usually I leave them as 7 and 1 in the chute.
How far left was left? Was it at more than 7-10 yds grouping left?
Just curious..
Thanks for the report.