1) Northwest sector. Take the road north from the southeastern guard post until you see a chasm between two mountains to the west. On the side of the northern mountain facing the road is a diamond briefcase. On the eastern side of that mountain is the AK
2) East sector. All the way at the southeastern exist along the road, in the same area as the diamond briefcase.
3) Southwest sector. From the guard post in the center of the map, draw a straight line south until you hit the north side of a mountain. The AK is there (It's actually slightly to the west, but you'll see it).
4) Southeast sector. See the lake on the west side of the map? The place where the lake ends and meets the west side of a mountain near the center-west portion of the map lies the AK (If you draw a straight line north of it to the road, you'll see a guard post).
The other four are in the southern district. BRB with those.
5) North sector. In the southern edge of the map, north of the mountain. If you look at the Safe House in the central / southwestern portion of the map, it's directly south of that across the river (in the green area).
6) East sector. All the way on the east edge of the map, exactly in the middle. There's a mountain that jettisons out and maps the river curve into a C shape; The AK is in the north corner of that mountain.
7) Southwest sector: All the way at the east edge, about midway down the curvy road in the northeast. It is directly east of the center of TaeMoCo Mine, on the east side of the road just as it begins to curve to the east. (It's a long way away, but if you draw a straight line west of where the AK is, you'll see the Weapon Shop on the west side of the map)
8) Southeast sector. In the southwest corner, on the south side of the U shaped river.