The later part of this thread drifted into helmets and the protection they afforded http://www.ww2incolor.com/forum/showthread.php?t=2155&page=2 but I thought it might be worth starting a separate thread on that topic and related topics about of the effectiveness of basic infantry weapons in WWII.
No steel helmet in WWII was designed to resist, or was capable of resisting, standard military rifle rounds around .30 calibre at normal combat distances, which in practice were likely to be at 10 to 100 metres, although riflemen were generally equipped with weapons which were reasonably accurate up to about 600 metres and could easily kill at twice that distance.
Helmets were designed to provide protection against shrapnel; blast debris; and spent rounds, all of which could inflict fatal wounds without a helmet.
The design of most helmets reflect their purpose, with attempts to extend the shield beyond the head. The American / German approach was to extend a canopy down the neck to some degree. The British approach was to build a verandah (porch) around the head, which is great for overhead items but, unlike the American / German helmet, not great for low velocity but potentially fatal horizontal projectiles that are going to hit you in the upper cervical spine.
One of the countless tests showing what happens with steel helmets hit by rifle rounds is here http://www.philippinemarinecorps.mil.ph/c6_helmet.html
On the US M1 helmet http://www.olive-drab.com/od_soldiers_gear_m1_helmet.php
For video of what modern military rounds (including some equivalent to WWII rounds) can really do, including to Kevlar helmets never mind tin pots, instead of the usual movie nonsense http://video.google.com/videoplay?docid=6760530260633420235&q=30mm&hl=en