up the wazoo/out the wazoo is a phrase that means something is in great excess. Wazoo is used in place of "ass" to soften the phrase. Whatever you are reading/listening to is commenting on a situation where there is a lot of firepower (firepower up the wazoo) but no one willing or able to use it (no trigger finger)

it is a very odd phrase you will never see again and should not learn to use.