Side by Side Doubling

[Frontier Lone Rider]

I have a 12ga Stoeger Coach Gun Supreme which has started firing both barrels at the same time or doubling.  Last week it doubled four time in six stages.

 

What would make this happen and what would be the correction or fix to stop the shotgun from firing both barrels at the same time?

 

Frontier Lone Rider

[Perro Del Diablo]

Is it single trigger? I have seen them double when not tight enough in shoulder.

[Larsen E. Pettifogger, SASS #32933]

First thing to do is remove the stock and open the barrels and cock the hammers.  Pull the trigger and look for anything obvious.  E.g., dirt, stray piece of shot, broken or out of position spring, etc.  Your description is too vague to ID the problem.  When was the last time the action was thoroughly cleaned?

[Tarheel Doc]

I had this happen to me. The cause was loose forearm screws. Once I tightened the double firing stopped 

[The Original Lumpy Gritz]

Do a deep internal action clean and check EVERY screw for tightness. 

[Beartrap SASS#57175]

Perfect for when (as Biden says) you need to just step out on the balcony and fire 2 blasts in the air!

[Frontier Lone Rider]

On 7/10/2024 at 4:03 PM, Perro Del Diablo said:

Is it single trigger? I have seen them double when not tight enough in shoulder.

It is a double trigger.

[Frontier Lone Rider]

On 7/10/2024 at 4:47 PM, Larsen E. Pettifogger, SASS #32933 said:

First thing to do is remove the stock and open the barrels and cock the hammers.  Pull the trigger and look for anything obvious.  E.g., dirt, stray piece of shot, broken or out of position spring, etc.  Your description is too vague to ID the problem.  When was the last time the action was thoroughly cleaned?

It was cleaned right before the match.

On 7/10/2024 at 4:47 PM, Larsen E. Pettifogger, SASS #32933 said:

First thing to do is remove the stock and open the barrels and cock the hammers.  Pull the trigger and look for anything obvious.  E.g., dirt, stray piece of shot, broken or out of position spring, etc.  Your description is too vague to ID the problem.  When was the last time the action was thoroughly cleaned?

I will give this a try.

[Larsen E. Pettifogger, SASS #32933]

The double triggers are usually pretty reliable.  Some areas to check would be:

 

The sear surfaces and engagement to make sure they have not worn.  Purple arrow.  These would be the last things to inspect as they are not visible when installed in the gun.

 

The sear springs.  Yellow arrow.  Make sure one of them has not bounced out of its location on the top of the sear leg.

 

Dirt or lead pellet under one of the triggers.  Green arrow.  This could prevent the sear from fully engaging.

 

[Roger Rapid]

1) Do you know which trigger causes this? If not remove the rear stock and test one trigger and then the other. You can clearly see the hammers drop (Ideal to have snap caps in chambers to arrest the fall of the firing pins). But you don't have to keep cocking the gun to test this - the focus should be on which or both sears that get lifted when one trigger is pulled.

2) Check the single pin that holds both triggers in place and see if both triggers appear to hinge properly (they both hang on the same pin). If the pin broke or slid sideway (not likely) then the one floating trigger could lift both sears. You could have a faulty split-pin (also not likely but possible).

3) Check that each trigger lifts its corresponding sear (If not, you could have either a faulty trigger that is not aligned properly to its sear, or a faulty sear that is not aligned properly to its trigger. 

4) As Larsen suggested, check that both sear springs are resting over the sears and that one has not slid sideways and resting on both sears. On the Stoeger double-trigger models the sear springs rest somewhat precariously on a little notch on the the sears and could slip off (on the single-trigger models, the sear springs are bent at right angles and latch securely over the sears).

5) It is also possible that you have a broken sear spring. The sears are heavy enough, and balanced such that a sear could properly engage - but not securely - in the hammer's notch. In this case, the recoil would be sufficient for sear to lose contact with the hammer and cause a double detonation. (If you do have to order new springs, note that while the springs look very similar, the left and right springs are different.)

Roger

[H. K. Uriah, SASS #74619]

The other thing it's good for, if doubling, is for dispatching gruesome monsters at close range with a single shot, or large clusters of zombies as they are rushing you.  

DOOM!

[watab kid]

sounds like an exciting event depending on your load - i only did this once when i was favoring an injured trigger finger - got a bit confused on one stage which substitute finger i was using and caught both triggers ........dunb me - but the target was definitely down , had extra shells in the slide luckily , 

[Frontier Lone Rider]

19 hours ago, Larsen E. Pettifogger, SASS #32933 said:

The double triggers are usually pretty reliable.  Some areas to check would be:

 

The sear surfaces and engagement to make sure they have not worn.  Purple arrow.  These would be the last things to inspect as they are not visible when installed in the gun.

 

The sear springs.  Yellow arrow.  Make sure one of them has not bounced out of its location on the top of the sear leg.

 

Dirt or lead pellet under one of the triggers.  Green arrow.  This could prevent the sear from fully engaging.

 

Thank you for your time and information.  This will give me some place to start.

[Frontier Lone Rider]

11 hours ago, Roger Rapid said:

1) Do you know which trigger causes this? If not remove the rear stock and test one trigger and then the other. You can clearly see the hammers drop (Ideal to have snap caps in chambers to arrest the fall of the firing pins). But you don't have to keep cocking the gun to test this - the focus should be on which or both sears that get lifted when one trigger is pulled.

2) Check the single pin that holds both triggers in place and see if both triggers appear to hinge properly (they both hang on the same pin). If the pin broke or slid sideway (not likely) then the one floating trigger could lift both sears. You could have a faulty split-pin (also not likely but possible).

3) Check that each trigger lifts its corresponding sear (If not, you could have either a faulty trigger that is not aligned properly to its sear, or a faulty sear that is not aligned properly to its trigger. 

4) As Larsen suggested, check that both sear springs are resting over the sears and that one has not slid sideways and resting on both sears. On the Stoeger double-trigger models the sear springs rest somewhat precariously on a little notch on the the sears and could slip off (on the single-trigger models, the sear springs are bent at right angles and latch securely over the sears).

5) It is also possible that you have a broken sear spring. The sears are heavy enough, and balanced such that a sear could properly engage - but not securely - in the hammer's notch. In this case, the recoil would be sufficient for sear to lose contact with the hammer and cause a double detonation. (If you do have to order new springs, note that while the springs look very similar, the left and right springs are different.)

Roger

These are very detailed instructions.  I will be attempting to make any corrections I might find.

[Frontier Lone Rider]

I knew I could rely on the vast knowledge you pards have.  Could one get any better advice if they shot in any other type of competition.

[Roger Rapid]

Frontier Lone Rider... Please do post your findings...

RR