Been smoking on and off for the past year now, did a pork butt late last year and turned out pretty well. Just used a rub and that was pretty much it and it turned out pretty well. Today, however, after reading quite a bit and watching some videos, I decided to get a little fancier than usual. I used a rub and injected the meat with a combination of apple juice and Worcestershire sauce. I have a Masterbuilt analog electric smoker and wanted to smoke a 4 lb bone in butt, today. I have an oven thermometer to make sure I was sitting around 250, which I was and also a meat thermometer, that I kept in the butt to make sure I hit my internal temps. I was a little surprised when it took only about 2.5 - 3 hours to get to 160, at which point I took it out, spritzed it and wrapped it and re-inserted the meat thermometer. Took me about another hour to hour and a half to hit 197, which is what I was looking for. Took the meat out and let it rest for about 45 minutes. I used a different meat thermometer to check the internal temp and it was about 189 I believe. I assumed it had dropped some degrees just sitting there on the counter top wrapped up. Went to pull the bone out and I couldn't get it out. The meat was really tough and I just considered it ruined at that point. I just don't understand, all my temps were spot on and I have no idea where I went wrong. Funny thing was, a few weeks ago, I had almost exactly the same thing happene to me, and I later figured out the temp gauge on my smoker was completely off by more than 50 degrees. So I assumed buying the internal probe would fix my problem but apparently not. Was hoping maybe someone could suggest something or point out something I did wrong. Appreciate the help!