I've been hunting from a ground blind a lot this year and have been wondering if using the barrel of my rifle to slightly pull down the bottom on the zipper blind opening when making a shot would impact the shot? I keep the opening limited to just a couple of inches as the deer have been wary of the blind, despite it being in the brush and back from my food plot. I've scoped a few deer and want to keep little of the rifle showing through the opening when making a shot. The screen openings on the blind are too low to shoot through.

I know that resting a barrel against a solid object is a big no-no, as it will definitely impact the trajectory by impacting the energy that travels along the barrel. But would a liitle pressure from cloth and a zipper have the same effect?

Yup.

Don't rest the barrel on ANYTHING. Just becuase it is cloth and zipper doesn't mean the weight of the rifle isn't pulling it downward therefore flexing the barrel upward. Barrel contour and length dictate how much flex, of course. But no matter those two variables I wouldn't rest the barrel, ever. Get the forearm onto a rest and you're OK, provided it doesn't flex into the barrel.

I hunt out of a pop up blind as well. If you are ok with making a purchase to solve your problem, I use a Caldwell field pod for my rifle rest, and it works great. My pop up is big enough that I set my chair right against the back wall, and the rifle barrel is completely inside my blind. Nothing sticks out. Amazon has the best price I've seen on then, but academy and cabelas carry them too.

On the cheaper end, you could always just use a shooting stick, but I had the fieldpod given to me as a gift so that's what I use.
http://www.amazon.com/gp/aw/d/B005CF0MVK...i=AC_SY200_QL40

Thanks for the comments and feedback.

you putting the barrel on the blind or the rifles forend?
Here is what I use by BOG-POD

My intention was to stick only the barrel through a more narrow opening and use just enough down pressure with the barrel to widen it enough for a clear view with the scope.

Based on the feedback, I'll need to widen the opening enough so that both the scope and barrel are not obstructed.

With shots being roughly 100 yards or less, I might opt for my 30-30 with iron sights.

Yes, it will effect it. You will impact high. NEVER shoot with the barrel rested on anything or with pressure on the barrel. It WILL change your POI.

At Rifles Only, they have a "wire shot". You lay prone and rest your barrel (only the barrel) on top of a wire. You are aiming at a 3/4" or 1" dot. The POI shift is generally 1.1 to 1.5 mils (about 4"-5"), depending on wire placement and barrel pressure.

Just use the forearm to rest on.