When I first read the description of the talent i got impression that it let me clear a jammed weapon as a half action with no test needed and in the games i have been in that has been the same conclusion everyone else had. when i went back and looked at it closer however it would seem to imply that it only lets me try to unjam it reduced to a half action. have i had it wrong before now or am i just reading to much into it.

From the looks of it, yes, it seems it is only for the attempt.

Though considering it is a talent I would houserule it to clear the jam automatically because otherwise the thing just isn't worth taking.

Hum ya i think that is what im going to do other wies it seems kind of useless

Interesting. Do note that clearing a jam does not have a subtype. So if you had technical knock, you could try to unjam it twice in one round.

Unfortunately the unjam rules say "can attempt to clear it again next round." but I think that's an oversight that Technical Knock should overrule.

Interesting, it's different when compared to the description in Black Crusade:

"The character may un-jam any gun as a Half Action, but may only use this talent on one weapon per round."

So they nerfed the ability.