Depending on the range & conditions(safety SOPs, # of people there, distance of the targets, etc) you can get by without a 1911a1 holster. IF you plan to tote the pistol around as you set up targets, clean up, load magazines, etc, then I'd buy a simple no-frills belt holster.
There are many many holsters for 1911a1 pistols. Basic designs include Blackhawk Galco Unkle Mikes Bianchi DeSantis .
A choice you may want to see is the Bianchi M12 or UM92II milspec holster.
It fits 1911a1 type pistols & can be worn several ways; regular cross draw shoulder drop-leg/SAS, tanker.
CF
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