submitted by Kborum:
Remington 11-87 Barrel Seal Activator Correction
The manual that comes with this firearm shows this assembly incorrectly. A drawing is available from Remington illustrating the correct orientation of these parts. I am posting this to save you the trouble the rest of us had before this info was available on the internet from Remington.
The corrected illistration below is available at:
http://www.remington.com/images/support ... notice.jpg
From Remington:
The 11-87 Owner's Manual schematic has not been updated with the most recent version of the barrel seal activator. In this diagram the barrel seal, piston seal assembly and barrel seal activator are shown in the proper positions on the 11-87 Super Magnum magazine tube
A barrel seal activator is used on the 11-87 Super Magnum to improve performance when shooting 2¾” shells. You should remove the activator when shooting 3” and 3½” shells.

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