Right from the Remington manual:
MODEL 11-87™ SUPER MAGNUM™ OWNERS PLEASE NOTE: A BARREL SEAL ACTIVATOR IS USED ON
THE MODEL 11-87 SUPER MAGNUM FOR 23⁄4" LOADS. MAKE SURE THE BARREL SEAL ACTIVATOR IS
IN THE CORRECT POSITION (SEE PICTURE 31, P.17) FOR USE WITH 23⁄4" LOADS. REMOVAL OF
THE BARREL SEAL ACTIVATOR IS RECOMMENDED ONLY WHEN USING 3" OR 3 1⁄2" LOADS.
8. FOR 11-87 12-GA. SUPER MAGNUM ONLY:
Slide the barrel seal, barrel seal activator (when using 23⁄4"
shells), and piston/piston seal assembly from the magazine
tube. See Picture 23a.
IMPORTANT: A BARREL SEAL ACTIVATOR IS USED ON THE
MODEL 11-87 SUPER MAGNUM WHEN USING 23⁄4" LOADS.
REMOVAL OF THE BARREL SEAL ACTIVATOR IS RECOMMENDED
WHEN USING 3" OR 31⁄2" LOADS.
FOR 11-87 12-GA. (23⁄4" - 3") ONLY. Slide the barrel seal and piston/
piston seal assembly from the magazine tube. See Picture 23b.
FOR 11-87 20-GA. ONLY. Slide the barrel seal, barrel seal activator,
piston and piston seal from the magazine tube. See Picture 24.
Yes sir fully aware of what the original owners manual has printed BUT
Cheers
The but from others with the issue and matches what I was told
Somewhere on this site there was a discussion about the need for the barrel seal activator on the 1187 20 ga. I couldnt locate that thread, so I wrote Remington today as follows:
"Web chat groups debate whether the barrel seal activator on the 1187 20 ga. should be removed or not when shooting magnum loads. The manual says nothing about it for the 20 ga. So my question: was the 1187 20 ga. designed to shoot magnum shells (3” or 2 ¾” mags) with the activator installed?
Would it hurt the gun to remove the activator? My action is well broken in and will eject even light loads 8-10 from the gun. I would like it to eject shells closer to the gun and thought that removing the activator might reduce bolt velocity a bit.
I would appreciate if an engineer would respond the my questions or at least review the answer from tech support."
Here is the reply Remignton's tech support: "The barrel seal activator should only be used with low brass shells. The "rule of thumb" is basically to use it only when the gun will not cycle. Thanks,"
My further question is that if this is the case why does the manual say nothing about it. Does anyone on this form have thoughts on this?
And while I agree that Remington needs to address and revise their owners manual or at least send a revised attachment to those who have registered a 20 gauge gun with them. The statement in the manual regarding removal of the actuator for the Supermag 11-87 should clearly send up a red flag question to any 20 guage owners who are thinking of using the gun for 3" loads since their gun uses the same part.
Also, I finally spoke with a tech rep who was on the ball and understood exactly what my problem was, who told me that the activator should absolutely be removed when shooting heavy loads, he even said "it's in the manual", though I pointed out that the manual only makes that recommendation for the 12-ga Super Mag, not the 20, and he agreed that it was unclear and needed to be amended.
Thanks,