Strange ongoing flat problem.
 

So about 3 days ago I got a random flat tire, I pulled off the tire to check the tube, there was an obvious puncture but no sign in the tire or rim that could have caused it. I put in a NEW tube and thought I was ready to go. About 30 minutes later the tire was flat again. I pulled out the tube and there was an odd bulge/dimple thing going on, and it was on the outer part of the tube so i know it wasn't caused by the nipple holes and yes I do have proper rim tape. So I decided to use an entirely different back wheel, put a brand new tire on the different wheel along with another new tube. Again, about 30 minutes later it was flat.. Different wheel, NEW tire and NEW tube and it goes flat again. I go home and put in yet another new tube, inflate, wait, and sure enough, it goes flat again. I pull out the tube for the fourth time now and it also has the weird bulge/dimple thing going on.. I dont know if I got myself some faulty tubes or if my tire could be affecting the tubes, even though I checked the lining of the tire and rim and everything is smooth and fine. I'm wondering if the way the tube was folded on the box could have put a crease in the tube which would cause a defect when inflating the tube..

here is a picture of the bulge/dimple thing going on, you can see its towards the outside, so not touching the rim..
http://i55.tinypic.com/256xxjc.jpg

and heres a picture of the puncture, you can see how i turned it and the hole is more towards the side..
http://i52.tinypic.com/30be4bt.jpg

So you now have four tubes with the the same kind of hole in them?

Are the holes coming from the same area of the tire in relation to how far they are from the valve stem?

You don't happen to have tire-liner strips in the tires, do you? Mr. Tuffy or its generic equivalent? If so, the square-edged ends can chafe inner tubes, although it usually takes some time. The solution in that case is to feather the ends with sandpaper or a bench grinder.

Please don't get insulted if you're an experienced mechanic, but I suspect your problem is related to mounting technique. The damage might be happening at the section you push over the rim last. You might be trapping some of the tube under the bead of the tire, and as you inflate, it gets pinched. Usually this causes a blowout, but in your case it might get slowly pulled out from under, stretching and tearing the tube.

Next install, put enough air into the tube to make it round and stuff it well into the tire. When you finish mounting the tire, push the last section over and check that there isn't any tube peeking out under the bead.

I prefer to mount starting from the opposite side and working toward and finishing at the valve. Then I can push the valve up taking the tube deep into the tire before inflating.