How do other gm's handle this? I alllow it to go off normally, and when successful it adds 1d10 to the soak for that hit. Also, does anyone do any house rules for their use in melee combat? In a dark heresy game i played once upon a time, they acted like those in Dune, and didnt work in melee unless the hit was made by some amount of success, or an all out attack or something like that where someone had to specifically intend to penatrate the field that left them vulnerable in another way.

In the Battle for Rynn's World [a Space Marine battles novel] Pedro Cantor managed to bypass an ork's force field by using his gladius, which was neither a power weapon nor a chain weapon. So you could say that anyone making an effort to bypass the field, while using a normal weapon, would be able to. Maybe as a called shot. This is basically to represent that a force field is designed to deflect high energy blows and not those with relatively low energy. I would allow force fields in melee, it is so on the table top, and force field function is mostly based on translated rules from TT.

IIRC, force fields don't change the way they work when used against hordes. A successful roll negates all damage.

I use them as in the book. A percentage chance to stop an attack. Even the better fields have weak and strong points, and a horde attack doesn't have to be completely stopped (in the game universe) to negate any chance of it harming a marine (in stats). Full auto attacks are incoming within a span of seconds and can reasonably be all stopped if the field holds on that side for those few seconds (either the full attack goes through or not).

I like the idea of called shots to bypass, thats exactly the type of thing i was thinking of. I do allow them in melee or against hordes, but our group already had some homeruling from dark heresy, so i just built on it. I think Im gona keep the horde thing though, mostly because i had a champion standing toe to toe with rediculousness at full wounds and everyone else hiding behind cover in crit. I know its the rules, but it sucked for everyone so i just wanted to balance it out