I sneaked into the house earlier to catch Mythbusters!
I missed the 9 0'clock new stuff prog' but after that was a prog doing ''revisited'' stuff.
This time instead of firing from above into water - they fired under water. The semi was 9mm 239 - and this functioned well. However it seems the lethal range was not much more than 2 feet - by three feet a gel block was barely touched. Interesting demo.
What did not like being submerged was a SBS 12 gauge!! - that broke badly under the chamber area - as if back pressure acted on recoil shields very strongly - and they took care to get rid of all air in the system as with the other guns.
A .357 revo - Smith I think - did fine and survived, as did an M1 Garrand.
At 2 feet the 9mm penetrated about 4" IIRC and the .357 about 7" - nearly coming out the back of the gel. With all tests tho - seems like if you were about 10 feet away from a discharge - you'd be 100% safe - which includes the 30-06..
Forgot to mention - predicatably the SIG did not cycle fully - empty was caught between slide and chamber.