I offered to help some 155mm howitzer guys once (I was bored). I could barely unload a truck full of fresh ordnance. That's HEAVY! This gives "back-breaking work" a new definition. Oh, and remind them not to fire when you're standing next to the drive wheel.
Going after women in general is wrong though. If you want to do a certain job, pass the test, that's it. You can't be a gun bunny without serious upper arm strength (in the 90 percentile for men, too), so there should be by-occupation standards. If a woman can make the cut, go for it.
That brings back memories of my first night ops at Fort Stewart. We had just off loaded the 155 shells and powder to the guns and had crawled up in the back of the Duce and half. I was sleeping on the bench when they called a fire mission. I would guess the guns were about 75-100 feet from the truck. It raised my body off the bench. I yelled a variation of what in the world was that? The battery fired and all was silent. In the morning we were sent back to the barracks. Thrown off the range as it's called. Somebody was off on the coordinates and we had a short round. Next day we were back at it and quailifed for the year. Yea 155's go at about 90 pounds a piece I think.