Yes on the M4 feed ramps.
458 SOCOM port size is slightly larger than standard 5.56 port by about .120 inches. .025" on top and .095" on the bottom. This should not be a problem when done by a professional.
458 SOCOM port size is slightly larger than standard 5.56 port by about .120 inches. .025" on top and .095" on the bottom. This should not be a problem when done by a professional.

