(Matthew 27:3-8) – “Then when Judas, who had betrayed Him, saw that He had been condemned, he felt remorse and returned the thirty pieces of silver to the chief priests and elders, 4saying, “I have sinned by betraying innocent blood.” But they said, “What is that to us? See to that yourself!” 5And he threw the pieces of silver into the sanctuary and departed; and he went away and hanged himself. 6And the chief priests took the pieces of silver and said, “It is not lawful to put them into the temple treasury, since it is the price of blood.” 7And they counseled together and with the money bought the Potter’s Field as a burial place for strangers. 8For this reason that field has been called the Field of Blood to this day.”
(Acts 1:16-19) – “Brethren, the Scripture had to be fulfilled, which the Holy Spirit foretold by the mouth of David concerning Judas, who became a guide to those who arrested Jesus. 17″For he was counted among us, and received his portion in this ministry.” 18(Now this man acquired a field with the price of his wickedness; and falling headlong, he burst open in the middle and all his bowels gushed out. 19And it became known to all who were living in Jerusalem; so that in their own language that field was called Hakeldama, that is, Field of Blood.)”
There is no contradiction here at all because both are true. A contradiction occurs when one statement excludes the possibility of another. The Second Law of Logic, the Law of Non Contradition, (LNC) says that something cannot be both true and false at the same time and in the same sense. It is not a contradiction to describe something differently: Judas was hung and Judas fell down. Both are possible since neither negates the possibility of the other. A contradiction occurs when one statement makes another statement impossible but both are said to be true. So, what happened here is that Judas went and hung himself and then his body later fell down and split open. In other words, the rope or branch of the tree probably broke due to the weight and his body fell down and his bowels spilled out.
Also, notice that Matt. 27:3-8 tells us specifically how Judas died, by hanging. Acts 1:16-19 merely tells us that he fell headlong and his bowels gushed out. Acts does not tell us that this is the means of his death where Matthew does.