Pump shotgun: What is "twisting or binding"?

[Persuader12]

I see in advertisements for pump shotguns that they have dual action bars to prevent twisting and binding. What does that refer to? I have an idea, but I want to make sure I'm understanding it correctly.

I did a little test to see how I can handle a pump shotgun under stress in a home defense scenario. I did some pushups and other exercises real fast to get myself worked up to simulate the stress of a defense scenario, and then grabbed my shotgun (unloaded, of course) and aimed and pumped it as fast as I could. I noticed that under stress, I tend to twist the forearm to the right, and that makes it about twice as hard to pump as when I'm not twisting it. Is that what is being referred to? The SG I have is a Mossberg Persuader (hence my username), and it has the 2 action bars that connect to the forearm and lead into the receiver.

 

[entropy]

Yes, and the twisting is more with single action bars. Some of the earlier pump shotguns had problems with this, particularly less expensive models. Early Mossberg 500's (the model your Persuader is) had a single action bar, and were more prone to twisting (and resultant binding), at least until the steel action bar wore the aluminum away enough so it didn't anymore.

 

[troy fairweather]

Two bars put even pressure on the carrier, plus ad more reliability.

 

[bearman49709]

Prior to the Remington 870 most if not all pumps had one slide bar, Winchester 12, Ithaca 37 and Remington 31 to name a few. None of these ever had twin slide bars and the Ithaca still doesn't.
Along come the 870, to make it as smooth as the others Remington had to add a second slide bar then they claimed if a shotgun didn't have twin slide bars it would bind. Old pump shooters knew better but new shooters fell for it hook line and sinker.
Mossberg came out with the 500 with one slide bar and it worked just like the others had for years, but the new pump shooters bought into the twin slide bar BS and Mossberg had to add a second slid bar to compete with the 870.
I've owned two 500's with one slide bar and still own one, sold the other to a friend for his grandson. Never had any problems with ether.

 

[entropy]

In moments with a high 'pucker factor', as the OP stated, it is possible to twist action bars (single or double) enough to cause galling on the bars and receiver. It can slow the action down, and possibly bind it to the point of malfunction. Because you, or I for that matter, have not had this happen, doesn't means it hasn't happened. Whether twin action bars are BS or not, the only pump shotgun made in recent memory with one action bar is the SPAS, and that is because it is a semiauto that can function as a pump by locking the forend to the bolt carrier via the action bar.

FWIW, I like single action bar pumps also. My HD shotgun is an Ithaca 37.

 

[bangswitch]

I see in advertisements for pump shotguns that they have dual action bars to prevent twisting and binding. What does that refer to? I have an idea, but I want to make sure I'm understanding it correctly.

I did a little test to see how I can handle a pump shotgun under stress in a home defense scenario. I did some pushups and other exercises real fast to get myself worked up to simulate the stress of a defense scenario, and then grabbed my shotgun (unloaded, of course) and aimed and pumped it as fast as I could. I noticed that under stress, I tend to twist the forearm to the right, and that makes it about twice as hard to pump as when I'm not twisting it. Is that what is being referred to? The SG I have is a Mossberg Persuader (hence my username), and it has the 2 action bars that connect to the forearm and lead into the receiver.

Consider that a loaded pump gun takes more effort to rack the slide than one that's unloaded.

 

[George P]

Yes, and the twisting is more with single action bars. Some of the earlier pump shotguns had problems with this, particularly less expensive models. Early Mossberg 500's (the model your Persuader is) had a single action bar, and were more prone to twisting (and resultant binding), at least until the steel action bar wore the aluminum away enough so it didn't anymore.

It wasn't just cheap guns; even the older Ithacas did that on occasion

 

[Persuader12]

Yes, and the twisting is more with single action bars. Some of the earlier pump shotguns had problems with this, particularly less expensive models. Early Mossberg 500's (the model your Persuader is) had a single action bar, and were more prone to twisting (and resultant binding), at least until the steel action bar wore the aluminum away enough so it didn't anymore.

From what I see, my Persuader has a bar on each side. Isn't that what's meant by dual action bars? I also have a Remington 870 that has a bar on each side.

 

[George P]

Correct, but not every pump; especially those form some years ago, had dual action bars - thus the possibility of binding if twisting the forearm as you pumped.

 

[skeeterfogger]

Little dry film lube can help.

 

[Carl N. Brown]

The old Noble 66 (reworked as the S&W 914) had a single action bar.
I recall my S&W 914 functioned OK, but I didn't twist the pumphandle either (I'd heard twist and bind stories).
The Mossberg 500 and 590 shotguns I have used seem a bit more stable with two action bars and just one

 

[jaguarxk120]

Some of those shotguns with "Twin Action" bars need them, if they did not
have them parts would fall out with the barrel off!

 

[bearman49709]

In moments with a high 'pucker factor', as the OP stated, it is possible to twist action bars (single or double) enough to cause galling on the bars and receiver. It can slow the action down, and possibly bind it to the point of malfunction. Because you, or I for that matter, have not had this happen, doesn't means it hasn't happened. Whether twin action bars are BS or not, the only pump shotgun made in recent memory with one action bar is the SPAS, and that is because it is a semiauto that can function as a pump by locking the forend to the bolt carrier via the action bar.

FWIW, I like single action bar pumps also. My HD shotgun is an Ithaca 37.

I failed to make myself clear.
I didn't mean to imply shotguns with only one slide bar would never bind, as you said even twin slide bars can bind under the right conditions. The BS part was Remington saying in print ads that shotguns with only one slide bar would bind, while implying their 870 with two would not.
I doesn't even have to be a self defense situation, it can happen when under any stress like a flock of ducks dropping into your block or that big buck you've been after for three years walking 40 yards in front of you.
I've never seen any pump bind but I have seen people empty their pump at a flock of ducks and never hit one only to look down and find three shells laying beside them without a mark on their primers because they forgot to take the safety off.

 

[RMc]

... I have seen people empty their pump at a flock of ducks and never hit one only to look down and find three shells laying beside them without a mark on their primers because they forgot to take the safety off.

Interesting. Those people must have been well practiced at pressing the action release button!

 

[Fine Figure of a Man]

Operator error and cheap pump guns are the reasons for binding.
There is not a smoother operating pump gun than the Winchester Model 12 with its single bar. If you can make one bind, it's you not the gun.

 

[jaguarxk120]

And many of the binding, miss-feeds, fail to eject, and lock up's are due
to cheap shells.
Even the best of guns will fail with the ValuePack shells. It becomes even
worse on the $169 guns with poor machining and finish.

And the armchair gun smiths always recommend honing out
the chamber!!!

 

[Oldshotty]

I have seen people empty their pump at a flock of ducks and never hit one only to look down and find three shells laying beside them without a mark on their primers because they forgot to take the safety off.

Wait a minute, what?

 

[entropy]

And many of the binding, miss-feeds, fail to eject, and lock up's are due
to cheap shells.
Even the best of guns will fail with the ValuePack shells. It becomes even
worse on the $169 guns with poor machining and finish.

And the armchair gun smiths always recommend honing out
the chamber!!!

Because it usually works. Re-reaming it would be more correct, but on a shotgun, honing is sufficient.

The BS part was Remington saying in print ads that shotguns with only one slide bar would bind, while implying their 870 with two would not.

It did stretch it some, yes.

I've never seen any pump bind but I have seen people empty their pump at a flock of ducks and never hit one only to look down and find three shells laying beside them without a mark on their primers because they forgot to take the safety off.

As RMc said, they would had to have pushed the action release lever up three times for that to happen. While not impossible, the probability of it happening that way unintentionally is extremely small.

 

[jaguarxk120]

And why does the buyer have to finish the gun? When coming from the factory those guns
should function with all makes of shells!

I have several Ithaca 37's and a couple of Wingmaster's and they function perfectly
with factory and reloaded shells.

 

[bearman49709]

This was in 1975 or 76, I know one guy had a Mossberg 500 but he is the only one besides me who killed any ducks, one had Ithaca 37 since he was left handed and his brother I think had a 870. There was one other but I can't remember what he had. I think it was one of the brothers and the other guy that did it that time.
The next time was in the late 1980's or early 90's and I can't even tell you who was with me that time but he said the same thing about the gun jamming and how he had to push the release button to get it to work.
The funny thing is all three said they felt the recoil every time they pulled the trigger.

Interesting. Those people must have been well practiced at pressing the action release button!

 

[entropy]

And why does the buyer have to finish the gun? When coming from the factory those guns
should function with all makes of shells!

I have several Ithaca 37's and a couple of Wingmaster's and they function perfectly
with factory and reloaded shells.

I agree with you. But it is what it is. Shotgun shells should not have steel bases, but far too many do.

This was in 1975 or 76, I know one guy had a Mossberg 500 but he is the only one besides me who killed any ducks, one had Ithaca 37 since he was left handed and his brother I think had a 870. There was one other but I can't remember what he had. I think it was one of the brothers and the other guy that did it that time.
The next time was in the late 1980's or early 90's and I can't even tell you who was with me that time but he said the same thing about the gun jamming and how he had to push the release button to get it to work.
The funny thing is all three said they felt the recoil every time they pulled the trigger.

You do realize none of these shotguns will do what you claim without the shooter pressing (or pushing) the action release. If the Ithaca was an older gun then, it could have fired the rounds by just holding the trigger back, but then the primers would certainly have dents.
Perhaps 45 years have changed events as you remember them.

 

[George P]

Because it usually works. Re-reaming it would be more correct, but on a shotgun, honing is sufficient.



It did stretch it some, yes.



As RMc said, they would had to have pushed the action release lever up three times for that to happen. While not impossible, the probability of it happening that way unintentionally is extremely small.

I would not say "honing", but more like giving it the final polishing the factory didn't take the time to do

 

[bearman49709]

You do realize none of these shotguns will do what you claim without the shooter pressing (or pushing) the action release. If the Ithaca was an older gun then, it could have fired the rounds by just holding the trigger back, but then the primers would certainly have dents.
Perhaps 45 years have changed events as you remember them.

I've used pump shotguns for over 45 years and still own three, so I do realize they all work just as I wrote it.
You ether missed or didn't understand the part where all three claimed they felt the recoil each time they pulled the trigger,each time they shot the gun jammed and they had to press the release button to get the forearm to release so they could eject the empty and load a new shell into the chamber.

The strange part is that not only did the two from the mid 1970's but the one from late eighties early 90's all said the same thing when they found out what had happened, had it only happened with the first two I would have still believed as I did when it happened that they just agreed with whatever the other was saying to save face.
When the same thing happened years latter and this guy saying the same thing I now believe that their mind may be telling them they are shooting the gun and the guns will not eject the empty without pressing the release button kind of like the phantom pain some feel from missing limbs.

 

[mjsdwash]

I would not say "honing", but more like giving it the final polishing the factory didn't take the time to do

I honed mine, full break hone. Runs 19.88$/100 as smooth as a Win1200 with AA's

 

[entropy]

When the same thing happened years latter and this guy saying the same thing I now believe that their mind may be telling them they are shooting the gun and the guns will not eject the empty without pressing the release button kind of like the phantom pain some feel from missing limbs.

The term for that is "operator headspace and timing".