Occasionally, a rifle comes with a factory trigger that's quite nice, relatively speaking. My STAG came with a very clean 6 lbs pull. One trigger that is quite good but less expensive than either a Timney or a Geissele is the Rock River Arms one. I have installed one in a stock AR-15 and I am happy with it. I have installed two Geisseles in my target AR-15 and AR-10, respectively, they are fantastic. One should be careful stoning a factory trigger and sear not to go deeper than the case hardening and ruin them. Also, keep them lubed with grease.