A higher rep range (12-20 and even beyond) have worked like magic for a lot of guy's. Best for me seems to be 18-25 reps in partial compound movements, like squats, hack BB squats, Dl's, Hi-pulls and shrugs, to name a few. Even bent arm pullovers have proven to be one of the better upper body movements, surprising giving mass and strength, and rather quickly. For me anyway. For others, maybe not. We are not created equal when it comes to results (or failures) when lifting.
The most outrageous gains made, when starting to train with serious intent, was the heavy 20 rep breathing full squat. Followed by a set of pullovers right after. Two such sets usually had me fried for the rest of the workout. An example might be taking a weight you can do for 10 good reps (say 300 for the average lifter) and extend that to 20 reps in the same set. Stating with taking 3 deep breaths between each rep. getting to the 16-18 rep you may be breathing like a steam engine, wondering where your next breath will come from. Got me in the best shape for football, and with greatly improved stamina (strength plus endurance). Gain a bit above 20lbs also. All old school stuff...of course.
Good luck.