My experience with .40's is that the full mags are a bit tighter.
You could insert mag with the slide back, or...
Give the bottom of the mag a good rap with the heel of your hand to get it seated or...
Download the mag by 1 or 2 rounds.
I had one new mag in my 27 that was so tight when full that I couldn't pull the slide back. Disassembling the mag and trimming the extra plastic so the spring fit better, loosened it up some.
Irresponsible use of alcohol kills many times those killed by guns. And look what happened to PROHIBITION 100 years ago!