Then let the gun speak for itself :
If the full-length magazine had been shortened, the original forward attachment receptors in the bottom of the barrel (a cross-groove for the barrel band pin and/or a small hole for the mag end cap screw), near the front sight, will still be there.
If the SRC was born with the shorter magazine, the bottom of the barrel, up there near the front sight, should be as smooth as a baby's butt.
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