Instructions link
The diagrams are a little screwed up, but the link should clarify things.
I've built dozens of these...best built with galvanized nails or big ass screws.
http://www.kuci.org/~dany/firearms/targets.html
Poor Man's Target Frame
Welded target frames typically cost $25 or more. You can cut cost by building your own. They won't be as compact as welded frames might, but they will be functional.
Need:
One 8' 2x4
Two 5' 1x2s
Two short (6") 1x2 spacers.
Saw (and miter box if you are using a hand saw)
C-clamps capable of a 4" span
drill and screws, or hammer and nails
Procedure:
Cut the 2x4 into two 18" lengths, and two 30" lengths. Cuts should be an even 90 degrees so the ends will square well.
Clamp the two 18" pieces parallel to each other, on edge, with the short 1x2 spacers between them. The spacers should have the long side flat between the two boards, so that the gap between is the skinny width of the 1x2s--approximately three-quarters of an inch.
Place the clamped 18" assembly on a flat surface and put the two 30" 2x4s on edge, at a 90-degree angle to the other boards, centered. Nail or screw the joints together at the arrows:
Remove the clamps and spacers, and you will have a completed target-frame base. Each base will accomodate one IPSC target. They can be stacked for transportation.
When you want to shoot, set the base down, and insert two 5' 1x2s vertically into the gap. It should be a tight fit. If the 1x2s are too loose, wrap the ends once with masking tape. You will end up with a target frame five feet high, with a stable base, and plenty of surface area for stapling your target or cardboard backing to.