I also don't think that 400 is that much.
I take multiple guns. Last week I took two 9mm, one pistol and one carbine.
One 223.
One 44 special
And one 22 LR rifle.
I normally take twice what I think I will shoot and the 22 LR I took over 1000 alone since I had two bricks and then some. But I always keep that much in my range ammo bag.
I was there over 6 hours and only took breaks when the flag went down.
How much did I take and how much did I shoot.
Shooting alone it was more than 400.