Almost all shooting heads are 30 feet long. This more or less corresponds to the length of the “working portion” of a full fly line. You will find longer shooting heads, but 30 feet is pretty much the standard. It’s a little tricky, but you can shorten shooting heads to match your fly rod. Purchase a head that’s “over-weighted” for your rod, then start test casting and trimming. This is the recommended method for adapting such fast-sinking heads as SciAngler’s Deep Water Express. Remember that shooting heads should usually be one or two line weights over your rod’s rating.