From Behind Every Blade Of Grass

The 35 hardened 1 ESAPI plate with a DR 12/5* OTV...

Hit with your average hunting round, which is an expanding round.

That's 7d(0.5) pi+ for most common calibers (.30-06, .308, .270 Win).

You divide the armor's DR by the number in parentheses, 47/0.5=94.

Max damage roll is a mere 42, so an expanding hunting round just goes "spack" against the ESAPI plate, every time, never penetrating.

But wait!  That ESAPI plate is ablative.  The average hit is 24 and the plate loses 1 DR per 3 that hit it.  So, 8 per shot on average (2-14 range).  So about 5 hits will break the plate up enough to leave the wearer with just the OTV for protection.

Assuming the wearer stands there and foolishly laughs mockingly while his plate insert is ablated to nothing...  The DR 12 of the vest is also doubled to 24, just barely stopping the average 7d(0.5) pi+ hit every time (but there's the potential to get 18 through which will be upped to 27 if it does).

Please recall that the 12 is flexible armor and for every 10 points of damage it stops, the wearer takes 1 point of cr damage.  In this case, 2 points of cr damage with the average hit!

Of course, someone with a scoped hunting rifle firing soft-points is going to see the armor and aim for something more vulnerable, like the eyes, face or neck.