What type of Impulse model ?
I've heard of some models with sticky bolts, but all the one's I've handled were pretty smooth.
If you have the bolt handle facing to far rearward, you'll end up pulling up on the handle instead of rearward to unlock it, causing it to bind.
The bolt handle needs to be canted a little forward.
Also remember that its a straight pull and it'll take a little getting used to to pull the bolt straight back.
I use Kroil on my bolt and remember to lube the bolt release channel too.

SJC