I just ran into this exact problem. Even though the locking block fit well and the holes all lined up, it was still tipped like yours. I ended up stoning the front down until it fit. The gun runs fine and is tight on the rails. Not really sure how much I stoned off but guess it was at least 0.020". A call to customer service was certainly warranted but I wanted to get the gun running. Besides, since the holes lined up just fine I'm not sure a replacement block would have done anything different.