Rainproofing my Gunbox

I use a Pelican Case to house my gear and use it as a stand for my scope.

Am I allowed to use an umbrella for my gun box? I've been thinking of different systems to prevent water from entering the box but an umbrella would be the easiest method.

I imagine using an umbrella to shoot under would be unfair as I think it'd give an unfair advantage but what about just having a small umbrella for my gun box which I can peek at my scope with?

To specific rule…other than the general one about a piece of equipment giving you some advantage.

But most people use a large trash bag.  It doesn’t take up a lot of space but covers a lot.  Or a plastic tarp.

NRA National Matches Program states. No Umbrellas forward of the ready line. Does not differentiate use or type.
Not sure if current CMP rules still have same verbiage.

If you are going to be shooting in the rain, your stuff is going to get wet. Rain can be anywhere from vertical to horizontal. Just part of the game.

Surely only girls would want to use an umbrella? Oh, wait, it's Ashley!

umbrella mounted on your range cart, can't see why not, get a good golf umbrella(big) and not a cheap one, first good wind you will be buying new.

bumbershoots on the firing line restricts the visibility of the safety people....so not beyond the ready line.

The only thing I'd try to protect is my clipboard/score card which can go into a gallon zip lock bag.

While I wouldn't be overjoyed to watch everything else get wet I could get through the match and dry it out later.

Go with the 2 1/2 gallon ziplock bags, that way you can write in them without having to remove your clipboard.

I shot a match at Quantico once where it rained so hard with wind that I had an inch of water in my gunbox even under the roof.  After that I always carried a big black trash bag neatly folded in my gunbox.