It is not always the size of the anchor, too short of a length of anchor chain will also make it hard to anchor. You can have a heavy anchor, but you need chain infront of it not only to get it down easier, but also to let the line bow down below the anchor to chain connection so it can grab to set. I have about 15ft of chain on my anchor, it isn't a bigt anchor either, it's the same size I had on my 22' Grady believe it or not but I've anchored in 200ft of water with it. Not sure of the exact size, I can find out this weekend when I go back down if you would like. I believe it is rated for boats only up to 26', most anchor manufacturer's will have a recommended size range for each anchor, I'd buy one that you places your boat at the low part of that range, or buy one a class size up. The 265 is a big 26' boat and acts bigger, I'd say get an anchor for a 28-30' boat. I use a danforth and anchor in sand, mudd, clam and mussel beds and never have issues. Also, are you giving a 3:1 scope, in string currents in may need to be 5:1. If there is not enough line out most anchors will not grab or stay that way long. Hopefully this helps a little, if you need my anchor size I will get you that Friday when I get down there.