Bought a new to me 11-87 last year just before the season to hunt with and loved it. Time was very limited so I put on a saddle mount and put an existing red dot I had on it and went out the door. Looking at putting a Fasfire III on it but would like suggestions as to whether to drill and tap the gun and put a rail on it or if anyone has any experience with a speed bead mount for the FF III. Also , leaning towards the 8 MOA but would like to hear everyone's arguments on 8 versus 3. All comments and suggestions welcome...
I'd go with the FF III and a 336 mount. Makes for a very clean install. I like the idea of the Speedbead, but had trouble with the one I put on my 1187. Mount broke after just a few shots and would not hold zero. Burris was great with their CS and offered to send me another Speedbead mount or the 336. Went with the 336 and am very pleased.
I had my 870 drilled and tapped then mounted a picatinny rail on it and it made a nice job. I also use an FF III with an 8 MOA dot and don't have any problems with it being to big.
I put a 336 and FF3 on my 1187 20 ga.
(http://i33.photobucket.com/albums/d81/01Foreman400/46ACE34C-AECA-44D1-BBF9-0C43B963736D_zpsvbstli2e.jpg) (http://s33.photobucket.com/user/01Foreman400/media/46ACE34C-AECA-44D1-BBF9-0C43B963736D_zpsvbstli2e.jpg.html)