I did have the same model gun that the OP have. It would require a good cleaning to keep it working well. If I took care of it, it worked fine. I agree with the other people that have mentioned the hood of the barrel. I would agree with the emery cloth idea. If you do use a file be careful. I would probably stick with the emery cloth. When you are done, clean it really good. Then clean it again. You dont want to leave any tiny metal shavings in the gun. That would be even worse. I would not be afraid to shoot the gun after you clean up the burs. Just take good care of it, and clean it after every trip to the range. No, it will not be a family heirloom to pass down to your children. But you can enjoy shooting for a while until you save up for something better.
Romans 1:16 I am not ashamed of the gospel, because it is the power of God for the salvation of everyone who believes: first for the Jew, then for the Gentile.