It is 130 bushels, but by cu. ft., not weight. 1 US bushel =1.24445608 cubic foot.
It sounds as though what you are spreading may not be all that heavy, but I'd start out with a level load, or a bit over. If it has the three beaters, and it handled the level load OK, then not over the center shaft on the top beater, if heaped.
Fill it from back to front, but don't pile material directly on the beaters. That gives them a chance to be in motion, before the material gets to them, and not trying to turn/start under a load situation.
Not familiar with the 130 spreader, but most spreaders have variable feed rates on the apron chain. That is made possible, by an adjustment allowing the dog that catches in the ratchet gear on the apron drive shaft to move further, or less, jumping over more, or less teeth, to drive the shaft. You can spread lighter, or heavier if you want, but with heavier, more solid, or frozen chunks of manure, makes it a lot easier on the whole drive system, to feed slower.
If the apron chain has broken before, more than likely the detachable link apron chain is getting worn enough, that if overloaded, it will break a link. You can buy complete apron chains, with cross members, but they are pretty expensive. I put a new apron chain in my old Cobey spreader, about 10 years ago, but bought just the chain, cross member attaching links, and rivets, for a lot less money. It took a couple of days, but was a good winter time project in the shop.
