11-87 Extraction Issues - Piston, seal, barrel seal?

[hit-man]

I have an 11-87 Police that will extract about 90% of the time using Winchester 00 buck. Slug shells cycle and extract with authority. I was thinking that it may be the piston seal or barrel seal, but I have not had this shotgun long enough to be that familiar with the operating system. Any ideas?

[3GunFunShooter]

I have an 1100 Competition Master, 7 years old.
Keep it clean and oiled. I changed my piston to the one from Brownells, change seals each time I clean it. Rem oil on the trigger group, bolt and Mobile 1 on the action bars. Polished the chamber. Switched to Win AA shells.
Went to a Surecycle recoil spring, drilled out the gas ports to .110.
I still have issues with it, but not as bad. Can't trust it anymore. Ran fine for 3 1/2 years and then problems.
Buying a Benelli, too many problems with the Remington, mine and other shooting friends.

[aippi]

The 11-87 P has little to do with any of the 1100 or sporting Remington 11-87's. I have one and it only works well with high power loads. Mine loves Wolf 00 which is hotter then other brands. I just test fired two 11-87P models I built and they ran perfect with the Wolf. So since your weapon is running fine with one brand of slugs, you have to suspect the brand of buckshot you are using and not the weapon. Get different ammo and find the one that works. These weapons have to have a heavy load to run properly.

[hit-man]

I'll try some of the Wolf and see how it cycels. How often are you changing the barrel seal (o-ring)? Is there any need for changing the port size?

[3GunFunShooter]

I change my O-ring each time I clean it. I got a pack of 50, so I have enough.
Opening up the gas ports allows for more gas to operate the action with 3-3 1/4 dram loads. JP Rifles use to offer an 1187 that they worked on for 3 gun. Guy I shoot with has one and ports were enlarged and some other magic tuning, and it has run with no problems for 5 years. JP does not offer it anymore.
As mentioned earlier, I use my Remington for 3 gun competition along with some other 1187 shooters in our USPSA club, who are starting to have problems with their 1187, parts breaking, cycle problems. I am using low base bird shot, some low recoil buck and reduced recoil Remington slugs. Just find a load that works for you and keep the ports clean.

[maxicon]

I don't think the o-rings get any wear in normal shooting, though it's cheap enough to change them. If they're getting nicked or torn, there's usually a burr that's catching them as they slide on or off.

It's pretty easy to open up the gas port a little. The downside is that making it more reliable for lighter loads means it'll run harder on heavy loads, so you have to figure out what's more important.

I have an 1100 20g magnum that I wanted to shoot low power loads in. I calculated the area difference between the single gas port in the magnum barrel and the double gas ports in the standard barrel, then used some precision drill bits to open it up. My first cut was smaller than needed on purpose, and it was better, but didn't throw the empties very far, so I went on up to the full size. It runs fine now on inexpensive target and game loads.

This only took a few minutes to do once I had the numbers down. If you mess it up, you have to replace the barrel.