Unknown gas screw on Remington 1100

[SwedishGuy]

As many others I'm trying to get my Remington 1100 12 ga to repeat light loads as well as hunting loads. In this effort I've been taking it apart, everything except the trigger unit and the breech bolt and cleaned and lightly oiled. I've also done some maintanence, replacing the gas piston, the piston seal and the barrel seal. I've cleaned the gas ports (holes from barrel to piston).

Before cleaning it reloaded hunting shells all the time and light shells most of the time. Now it does not reload light shells at all but reloads hunting shells nicely.

When cleaning the gas ports I had to unscrew a small screw that I have never seen in any picture nor seen it described. It is placed on the barrel, and goes through the gas channels. I had to unscrew it to be able to clean the gass channells (there are two channels).

The position of the screw


Closeup of position


My drawing of the actual screw (sorry, I didn't think to take a picture of it when it was out and it was hard to remove and is now secured with a drop of paint so my lousy drawing has to suffice). The longer part is where the groove for the screwdriver is.


Anyone know what this is and why it's there?

Any documentation on this?

Can it be that when I put the screw back I didn't screw it back to the same position it was before cleaning and thus the gas ports are partially blocked and that is the reason to why the gun will not reload lighter loads?

Best regards
SwedishGuy

PS: Excuse my english, it's not my native language. I'm here because swedish boards don't have too many Remington 1100 users. Thanks for your patience.

 

[Blue68f100]

That's something you normally never take out. Yes it can restrict the gas if not in the correct position. I would setup some kind of low pressure air to pressure the barrel, then adj it for max flow. You should be able to hear the difference.

btw, Welcome to THR.

 

[SwedishGuy]

That's something you normally never take out.

Strange though, in descriptions of cleaning the gun it says to push a 1/16" pin through the gas ports. In order to get anything at all through the gas ports I had to remove the described screw since it was (partially) blocking the ports. That is also why I'm so confused by the screw, never seen it mentioned anywhere. Could it be something someone put there after it left the factory...

I'll try your idea with air and turning the screw when I can muster the energy and courage to take that apart again. And thanks for the welcome!

btw: I've had the barrel shortend on this gun, it's now 19" which I suppose doesn't help in reloading light loads...

 

[Kp321]

I have been working on 1100's since the 1970's and have never seen that screw so I would say it is an aftermarket add on. It is a good idea if you want to restrict the gas but most 1100's need more gas, not less as they age. Maybe the ports are drilled larger then tuned with the screw?

 

[SwedishGuy]

I have been working on 1100's since the 1970's and have never seen that screw so I would say it is an aftermarket add on. It is a good idea if you want to restrict the gas but most 1100's need more gas, not less as they age. Maybe the ports are drilled larger then tuned with the screw?

Thank you, that's what I suspected, that it wasn't factory done. I do believe the ports are enlarged since they are at least 1/12" (2 mm) each.

I'll just have to experiment some with the screw and the guns reaction to different settings with different shells (loads). I suppose I'll have to accept questionable reliability in reloading light loads in order not to destroy the gun when shooting hunting loads.

What part(-s) in the receiver takes the recoil force from the breech block?

The spring that goes in to the stock, yes, but does the breech block buffer (I think that's its name - number 14 in this picture http://www.gun-parts.com/remingtonshotgun/Aug15_02.jpg ) also handle some of the recoil forces? On my breech block the buffer is not flush with the end of the block but somewhat (very little) depressed into the block. Should I replace it?

 

[entropy]

Looks like a home-made gas shut-off for shooting Trap at ranges where if it hits the ground, it's the clubs hull. The person you got the gun from should have disclosed it to you, unless they didn't know either. You'll have to play around with adjusting it. When you get it right, put a drop of clear nail polish over it to hold it in place.

 

[eastbank]

I just checked the 8 extra barrels I have for my 1100,s and non have a screw there, I think its a add on after it left the factory.eastbank.

 

[SwedishGuy]

Thank you all! I now understand what I'm dealing with here.

 

[eastbank]

the magnum barrels(3" chambers) have one gas port and the regular barrels(2-3/4" chambers) have two gas ports. to regulate the pressure from standard loads and magnum loads it makes no sense to me to block one of the ports in a 2-3/4 chambered barrel to shoot 3" magnums, as the chamber(2-3/4) would be short and the ejector would be in the wrong place in the barrel extension. eastbank.

 

[SwedishGuy]

it makes no sense to me to block one of the ports in a 2-3/4 chambered barrel to shoot 3" magnums, as the chamber(2-3/4) would be short and the ejector would be in the wrong place in the barrel extension. eastbank.

When I talk about different loads I am consistently referring to 2-3/4 shells. The "light load" is skeet ammo with less pellet weight (and less gun powder?) while "hunting loads" refer to ammo that is fully loaded with e.g. US3 pellets (and more gun powder?). Sorry that I've caused confusion.

 

[eastbank]

my rem 1100 12ga 2-3/4" shotguns will shoot light skeet-trap loads, I load 7/8 ounce loads and heavy 1-1/2 ounce loads for turkey that work with out any changes to the barrel or shotgun. I guess plugging one the gas ports would allow higher pressure loads to be used in a 2-3/4" chamber. eastbank.

 

[mnrivrat]

Actually that is a rather clever idea. ( yes - not factory ). Position of the cross screw would have to be precise , but it gives one an adjustment of the gas ports allowing you to change the amount of gas provided to the piston. An example of where that might come in handy is if you shoot heavy loads you could adjust the gas ports to create less stress and recoil on the gun. An interesting modification - adjustable gas system.

 

[eastbank]

I saw a .30 caliber m-1 carbine with a allen screw the blocked the gas from reaching the gas piston, in effect making it a manuel straight pull rifle 25 or so years ago. eastbank.

 

[Virginian]

That was apparently done to many if not all European export Model 1100s. It allows one to adjust the size of the gas ports to suit the loads being used and was likely deemed necessary because many European loads are lighter than the normal American loads. A really good idea in my opinion. Alas, they also knew better than to trust Americans with any adjustments.
On the one I have seen in person the blocking parts of the screw were tapered a bit.

 

[mnrivrat]

"That was apparently done to many if not all European export Model 1100s."

I've serviced a lot of 1100's over the past 40+ years and never seen one, or heard of that feature for export guns. Thanks for sharing - I just learned something new.

 

[eastbank]

did they enlarge the ports? if not the blocking screw would have no effect on low power shells. I would think the blocking screw would be more for shooting heavier than normal loads. as its a 2-3/4" chamber and rated for all factory high brass baby 2-3/4" magnums, it would only help on heavy reloads by reducing the gas to the action. eastbank.

 

[mnrivrat]

If Virginians information is correct they would have had to enlarged the ports as you say. That would be the only way to increase the gas for lighter loads.

 

[Blue68f100]

A thought. Try using just a short screw that will not block any gas and see if it works on the light loads. If this works you may only need to install it for the heavier loads. Or partially block 1 port.

Do you know what the size is, SAE, Metric?