Gas Ports On 1187

[k tyler]

I have a Remington 1187 that is only really works well with heavy loads and won't cycle low recoil slug. If it is freshly clean it will cycle number 6 with 3 dram. Once it get about a box through it, it becomes unreliable.

I have been told to open up the gas ports. Sounds good but how much do you open them up and can one do it at home.

[George]

Yes it can be done at home. As with any home project, do it carefully.

The gas system likes to be lubricated with a good hi-temp lube (synthetic motor oils and Remoil work well). Try cleaning lubing and putting a fresh O ring in first. The O rings need to be replaced when worn and this alone may fix your cycling issues.

Before I did a lot of things to it for other reasons and then had to drill out the gas ports, my 11-87 cycled 2.75 and 3 dram loads very well as long as it wasn't really grungy and had a good O ring in it.

Brownells has the good Teflon O rings available:

Brownells 11-87 Gas System Kits

I would suggest trying an additional (2nd) O ring on top of the single one that is there if a new one alone fails. If this does the job, then you haven't done anything permanent and you can remove it if you want. The same goes for the Activator ring that can be added instead to achieve the same result.

Activator Thread

If you choose to drill, first determine the drill size that fits in the port as is and then clean up the existing holes and test it before opening them up as that may just be enough. If not then select the next drill size up and drill out one port only first and test it before drilling out the other. I have a friend that opened his up to .120" and that was perfect for his gun. I know that mine were originally .080" before I opened them up. I had to go to .160" because of the gas bleed off porting and a recoil reducer caused.

Get the barrel clamped in place with ports up and facing you and just follow the old hole carefully and don't let it chatter or chip. A sharp bit, some cutting oil, and a steady hand are all that is needed.

Regards,

[benny hill]

usually about .110-.120 is about right.

[Flexmoney]

Does barrel length figure in to how big to make the holes? If so, how much?

[TMC]

For my open 1100 after installing the JP brake I took the ammo I had settled on using from now on in that shotgun, when to the range with a cordless drill and a bunch of bits in 1/64 increments and started shooting and drilling. Don't remember what size I ended with but it hasn't failed in 2 years and that receiver doesn't look like its getting battered.

I though it would be a neat idea if some smith with good tools could drill and tap the ports for allen head plugs with different size holes in them like carburetor jets. Then you could tune you shotgun for different loads. Large holes for the light skeet loads and the change to smaller holes for full power slugs.

[AH6IP]

Try the new gas ring/activator first. Call Rem or look up their web site and they will send you one free. If that still doesn't work, go .005" at a time larger til it does work. Benny posted the magic number. I believe .125" (1/8) is the max you want to go(no barrel porting/comp).

[SGDM]

Jerry is right...because I told him. I added the new gas ring and opened the ports to .100 and the gun runs everything. The max is .125 and is highly reccommended to reduce malfunctions. Like George said...oil the crap out of it.

[SVI4ME]

My 11-87 did the same thing. I got on the Remington web site and found that they send a ring that goes next to the gas ring for free. They made the ring to go with the 3.5 in. mag 11-87's to cycle light loads. Works great for light loads but if you use heavy loads pull off the ring.

[DblTap]

The ports on my 1187 21" Turkey gun were approx .072" stock. It would require 1 1/8 oz 3 1/4 dram loads to run reliably. I opened the ports to .080" and now the gun runs on 1oz 3 dram loads. With magnum loads (sometimes it's nice to stand at the first fault line and clean a 40 yard plate!) it occasionally "skips" over the next round in the tube due to high bolt speed. Maybe I just need a stouter mag spring...