Right. As I said, one possibility is that the Jewish leaders took the money that was Judas's and bought the field in his name. Another equally plausible theory is that in anticipation of his payment after first talking with the chief priests, he could have contracted with the owner to buy the field with the money he was about to receive. In either case, it's Judas's money that bought the field. In one scenario, Judas bought it directly (contracting between his nefarious deal and the payment of funds), and in the other case the priests are the ones who actually made the transaction with Judas's money and in his name. In both cases the field is called the Field of Blood, so both are talking about the same money and the same transaction, regardless of how the deal came down.

You think the order of events is

1. Matthew 27:5 And he [Judas] cast down the pieces of silver in the temple,

2. Matthew 27:5 and departed, and went and hanged himself.

3. Acts 1:18 and falling headlong, he burst asunder in the midst, and all his bowels gushed out.

4. Acts 1:18 Now this man purchased a field with the reward of iniquity;

Which seems alright, but Acts says "now this man", not anyone else.

There is certainly no contradiction. Both accounts can easily be true. A contradiction occurs when one account excludes the possibility of the other. The Second Law of Logic (the Law of Non-Contradiction) holds that something can't be both true and false at the same time and in the same sense. That's clearly not what's going on here: Matthew says Judas hanged himself, and Acts says that Judas fell headlong and burst open. First off, two different actions. Both are possible, since neither negates the possibility of the other. So, it's plausible, or at least possible, that Judas hung himself, and then later somehow (through a broken branch or rope, possibly) that his body fell and split open. Matthew tells us how Judas died; Acts doesn't tell us how he died, but of some happening surrounding his death.

Let's pretend two men are brawling—fighting to the death. Man A punches man B in the throat, crushing his larynx. He can't breathe any more, stumbles around, falls to the ground, and his head hits a curb and breaks open. So, the police come to the scene and ask witnesses what happened. One says, "The guy punched him and killed him!" A second guy says, "The guy couldn't breathe and died." And even a third claims, "He hit his head on the curb and his skull split open." Contradictions? Nope. They can actually be pieced together to create the whole story for someone who knows the whole story.

Here's at least a possible scenario: Judas takes the money to betray Jesus, and does exactly that. Afterwards, filled with remorse, he goes back to the priests. They won't take the money. In anger and guilt, the throws it into the temple courtyard and leaves. He makes his way out to a field, hangs himself, something breaks, and he falls to the ground and his body gashes open (or possibly when his body is discovered and people cut him down, his bloated dead body hits the ground and splits). The priests gather up the money, but they can't use it, according to the Law—it's blood money. It's still legally Judas', not theirs. They buy a field with his money in his name.

The Bible contradicts itself:

Acts 1:18: Now this man purchased a field with the reward of iniquity; and falling headlong, he burst asunder in the midst, and all his bowels gushed out.

and...

Matthew 27:5
And he [Judas] cast down the pieces of silver in the temple, and departed, and went and hanged himself.
These two verses describe two differing actions. In Matthew, Judas threw the silver into the temple, and then hung himself.

In Acts, Judas bought a field, but then fell down and exploded.

What's going on here?