I am a little confused on the manual for the 11-87. On page 15 it recommends removing the barrel seal activator when using 3-3 1/2" shells. It then states to remove the barrel seal and piston seal from the barrel tube assembly (2 3/4-3") only. Are they saying that during total disassembly you remove these parts or just when using those sized shells? Or is there another model that only handles 23/4-3" shells.

I am planning on using 31/2" shells but of the need arise I would like to know. Thanks.

I'm not 100% Sure but in my remington baikal I have a way to adjust the gun to shoot different sized shot. I think that you are supposed to remove these due to the increase in pressure when using bigger shot. I know a lot of guns need some type of adjustment due to different size shells but once again I'm not 100% on this.

I re-read the manual. I am pretty sure I just have to remove the barrel ring activator. I was just wondering if anyone else has an 11-87 SM. it makes sense that there is an adjustment to compensate for different loads.

Yeah, I'm willing to bet that is the case. My remington has a set of buffer rings that can be adjusted to the round. I do know my buddy bought an 11-87 and shot 3 1/2s without doing anything but assembeling the gun and it jammed on his first shot... we cleared the jam and on the 2nd shot it jammed again. I'm wondering now if not removing that ring caused the weapon to jam that way.