I haven't seen this get mentioned, but has anyone considered training with a slightly heavier rifle?

To preface this I want to say that while many only have one rifle, I know some people have "trainer" or "beater" rifles they use for classes, drills, training &c.. Then they have a separate "go to" rifle that usually stays mostly unused waiting for the day that it really has to get used.

Now as far as these training/beater guns go, I always figured that having as close of a set up to your primary rifle would be the smartest way to go about (ie train like you fight).

Would there be any benefit to purposely setting up a training rifle to be heavier in weight than the primary? For example, having a thicker profiled barrel with a heavier rail set up on an AR, when your primary is a LW barrel configuration. In a sense making shooting, performing drills with the primary easier?

It's just an idea I got when target shooting offhand. I went from shooting a VEPR AK to an SGL; to any one familiar with AK's it is about a pound of difference. Not to be captain obvious here but going to the lighter rifle made going through the full 30 rounds much less fatigueing.

Sort of the same logic as running with ankle weights if it makes any sense.