Four or more of those magazines on your chest is HUGE.
I use Tarzan M22 and NeVa vests or double rpk pouches with it.
Seriously 4 of those mags should be placed on the battle belt around your waist if you want to lie down properly. RPK Smersh would be perfect for that. Sad thing that only pictures I've seen Bizon in use have Tarzans in them.