I'm a newby getting ready to install my first hardwood floor (5" engineered). Everything I've read is mess, mess, mess. Has anyone tried using a bulk caulk gun to apply the adhesive and if so how did it work. Bulk caulk gun is the kind that you suck the material out of a 5 gallon bucket.

We're using that type of gun on a job now. However, we're using adhesive sausages and not sucking up adhesive out of a can. The gun works great, IMO. But if you are installing engineered, you may have to use a trowel, especially if you are going over concrete. I am installing a 6" wide solid over plywood, so we're nailing and gluing. If you're planning on stapling as well as gluing that 5" engineered, be sure to speak with the manufacturer to see if using the bulk gun method is OK for their product. BTW, I installed a 5" wide by 1/2" thick engineered plank made for LL by stapling only, using my M111 FS, the 1/2" shoe and 1.5" staples. It worked fine. No squeaks or noise from the floor. I used Aquabar "B" underneath it.