The primary counterweight for my L4701 is a 525lb BB1572 with about 100lb of 3/8” Grade 70 chain strategically draped on it. I like that setup because the property is large enough it isn’t uncommon as I’m just trying to go somewhere to do something I run across a fallen tree that needs moving out of a trail or some minor touch up that’s warranted on a trail or creek crossing, and it’s handy to have the boxblade hanging off the back or a chain to pull whatever. That and in comparison to other heavy 3 point implements go, it is fairly compact and rugged enough to serve as a rear bumper. For instance, my chipper is heavier but it extends further off the back, even with the chute folded in transport position, and if I accidentally back into a tree or dirt bank (like that has ever happened
) I’d much rather do that with the box blade as opposed to the chipper.
However, if, due to space limitations, you’re looking for the most compact counterweight, it’s either fabricate something as suggested above or buy a weight box and put sand, gravel, scrap metal, or some similarly dense material in it to provide the amount of weight needed.
You could go with something like a Heavy Hitch and hang standard tractor weights on it, but a weight rack type system for the 3 point, while effective, seems like a pretty expensive way to solve your problem unless you already have the requisite tractor weights.
Just to be clear, I’m not recommending you run out and buy a BB1572. It’s a good fit for my L, but suspect it would be a bit much for yours to perform well when used for boxblade work.