I did several bags of chicken yesterday using this method and as suspected it isn't as good as a vacuum seal how could it be.
But it did do a better job than nothing and I am not going to suck on a bag of raw chicken.
Here is the deal if you put a bag under water 1 foot with a hole in the top to let air escape.
At the one foot level you have 0.433 PSI of pressure pushing on the outside of the bag.
Here is something to think about.
It you put a bag in the freezer and the freezer goes on a vacuum like mine does the bag puff up?
Of course it does.
We never see it because when we open the door the pressure increases to normal.
Worth