rem DeadFish - I have set this up.. its a variation on the PUT command.
It should do what you want;
get $target,$rel,$second in $loc,$loc;
if $target > 0 then trysecond else fail1;
##trysecond:
if $second > 0 then continue else fail2;
##continue:
set $target's host to "";
set $target's hosthow to "";
set $target's pose to "";
say 'msg',"BOOM !";
say 'shoots',"[$actor] just shot [$target] with [$second]!";
say 'reloads',"[$actor] reloads [$second] - click click";
look $loc;
msg $loc,$actor,0,0,'force',"force:look $loc";

##fail1:
var $click_cmd to 'shoot';
var $click_mid to 'with zzzzz';
var $desc_intro to 'Click on the object you want to shoot:

';
look $loc,list;
msg $loc,$actor,$actor,0,'force',"force:look $loc,list";
##fail2:
var $click_cmd to "shoot $target with ";
var $desc_intro to 'Click on the object you want to shoot with:

';
look $loc,list;
msg $loc,$actor,$actor,0,'force',"force:look $loc,list";