Keeping a pump shotgun fully loaded and its affect on the magazine spring?

[bubba in ca]

All very interesting. I just leave my HD shotgun with 1 round short in the magazine but 3 rounds in the elastic cuff. Not too hard to load another round as I pull it out of the safe.
The gun has the original factory 5 round magazine, so I presume the engineering is correct. I`d worry more with aftermarket add-ons. But then I don`t have aftermarket add-ons.

 

[Cop Bob]

Just my observations over the years...

We have found 45 Colt mags that were loaded for 40-50 years and still functioned fine...
My personal 870 has been in a loaded and ready state since the day I bought it in 1971, With a mag extension, works just fine..

Same with many AR mil spec mags.. no issues...

I cannot speak to the metallurgy of Mossbergs.. .

 

[withdrawn34]

I think a new magazine spring could be "weakened" by keeping it fully loaded - but I prefer to call that breaking it in. After that point, it doesn't seem to make as much of a difference, or at least, it shouldn't, unless Mossberg is using some seriously low quality metal in their springs.

As far as whether most popular pump shotgun designs are drop safe - excellent question. It's a question that has been debated quite a bit on gun boards. Unfortunately, what often happens is that people avoid the question entirely, and start replying with "oh well why not just load a round when you need it?" or "I never keep one in the chamber." Neither of these comments address whether a shotgun is drop safe.

I am of the belief that for the most part, a popular model pump shotgun isn't going to discharge if dropped from, say, 4 feet. But again, I can't make a really strong claim about that, because I really do not know. I don't believe there's any sort of firing pin or hammer block in a 500, 870, or other actions based on those actions.

I've thought about dropping my shotgun with a cocked hammer, safety off, and empty chamber, just to see if the hammer would fall, but didn't want to mess up my sights (yea... I know, maybe I'm a wuss, but I like my sights!). I have tried to slam it down on the ground on the buttend (of course, my recoil pad absorbed a good amount of that force, so I don't know if it really proved anything), tried dropping it on the side from about two feet, and just yesterday, rested the buttsock on a solid surface, then took a non-marring mallet/hammer and whacked the muzzle straight on several times with a good amount of force (the scenario most likely to produce an AD is dropping it straight on the muzzle). Nothing happened, but I don't know exactly how much force I was applying. I don't know if it was really equivalent to a fully loaded shotgun hitting concrete ground, muzzle first. I didn't want to beat it up more because at that point, I just felt like I was abusing it.

I currently don't keep my SG loaded at home, but if I did, I'm wondering whether it would work to have a shell "half" chambered, that is, drive the bolt closed, but leave it open about halfway. This way, if you need it, all you ahve to do is drive the pump forward just that bit. This should be very quick, and should alleviate most of the noise issue from a full working of the pump action, but should also leave the shotgun unable to fire accidentally... I'm assuming it can't fire it the bolt isn't fully closed. Maybe that is a bad assumption?

 

[Rustinthewheel]

OP, I do not leave my Mossberg chambered, but I do load to capacity.

A small tip for when its 0200 and some goblin decides to go wandering about causing harm, is to clear the gun, pull the trigger and then safety the gun prior to loading your tube. This removes the step of pushing in the action release prior to making ready.

Then again, that step is one more chance to consider who you're shooting at so YMMV.

 

[Ironclad]

rested the buttsock on a solid surface, then took a non-marring mallet/hammer and whacked the muzzle straight on several times with a good amount of force (the scenario most likely to produce an AD is dropping it straight on the muzzle)

I might be wrong, but I think this test is slightly flawed. The dropping muzzle down scenario requires that both the shotgun and the firing pin be moving in the direction of a firing pin strike. Then the gun comes to an abrupt stop while the inertia of the firing pin lets it continue, against the spring, to hit the primer.

This could be tested in reverse, with a sudden movement of the gun and shell smacking the the primer against the firing pin, which would be held momentarily stationary by inertia. However, it would require that the gun be allowed to move, and not be resting against a solid surface like in your test.

Also, this would not cause the hammer to fall, so the only way to test this would be with a primed hull.

 

[Virginian]

The stresses created in the steel in modern coil springs are way below the plastic range. Thousands of cycles may have an effect, but leaving one compressed does not. The older leaf springs operated at a much higher stress level and were much more likely to take a set from being compressed, and this was exacerbated by temperature changes. That's why coil springs were invented.
Pick up a copy of Shigley's Mechanical Engineering Design and all shall be made clear - if you can handle the calculus.

 

[Fred Fuller]

A military note/warning on shotgun drop safety - http://www.thehighroad.org/showthread.php?t=571938

lpl

 

[BigG]

I guess it's a little late for you but based on what Mossberg said as quoted above, I would not own a Mossberg that couldn't be stored loaded. jmtc Guns are tools. They are supposed to be useful. A gun that can't remain loaded is not useful.

 

[788Ham]

Go over on the pistol thread and ask those gents over there about the springs in their firearms. I'll bet they tell you the springs get weaker by loading and shooting the mags empty, not by storing them with ammo. Its the cycling of the spring, working it that weakens it. Springs were made to compress, correct? Then loader' up and stand it in the corner and wait for the BG to pound on the windows! I'll bet you can't tell a spring has weakened after 2 - 3 weeks of being loaded either! JMHO

 

[RobV]

Again, thanks for the thoughts that were directly associated with me and my question... especially the reference to the other forum link on drop safety, which seems to put that issue to rest, as to whether or not there was any risk, independent of SOP.

I really didn't expect such a response, but it was good to hear the different opinions as well as the different ways you handle your own guns, over time. It really helped me get a high level look at the entire issue.

I hit the range tomorrow and looking forward to getting comfortable with my new best friend and trying to wear out that spring by having some fun

 

[ants]

Has anyone talked about the different spring materials?

Nearly all industrial springs take a set. Some more than others, some almost none.
Nearly all industrial springs fatigue. Some fatigue quickly, some last a lifetime.
Nearly all industrial springs go flat. Some go flat by next Tuesday, some go flat next century.
It's all in the materials and material treatment.


Music wire springs do take a set early in their lives. Later, they shorten when they get fatigued.

Chrome silicon springs don't do that so much. They also cycle a million times more before fatiguing.




Most members of the gun manufacturing industry save two dimes per spring by using music wire springs. They don't last very long, then you have to buy a new one. A few spend the extra two dimes and use chrome silicon springs that last virtually your lifetime.

If one gun manufacturer warns about its product, probably because they know they use cheap crappy springs.
That doesn't mean EVERY manufacturer uses cheap crappy springs.


Here are a couple food-for-thought items for you.

• If all springs fatigue as badly as gun springs, then why does your automobile throttle spring last a lifetime without going flat? It gets cycled a couple hundred times each time you drive. Perhaps 10 to 20 thousand cycles per year for 10 or 15 years. Yet a gun spring goes flat after 2000 cycles.
• If keeping a spring under load causes it to go flat, why isn't your car sitting on the ground by now? The four springs have the entire weight of the car on them continuously, LITERALLY continuous, but they don't go flat at the end of the year like a gun spring. Hmmm.
• This entire two-page discussion might be helped by an examination of the materials and quality of common gun springs. (Hint: They are generally crap.)

 

[Owen Sparks]

There was a story a while back about someone in France finding a Sten gun and five fully loaded magazines hidden in a wall since the German occupation in WWII. They turned it over to the local police who took it to the range and found that it fired perfectly. They shot up all the live ammo and then put it in the local museum. The springs did not take a set after being fully compressed for over 60 years.

BTW, you can buy spare magazine springs if you are worried. I have a few because I shoot in compitition some and it is the constisnt losding snd unloading that wears springs out, not static compression. There are after all several other smaller springs in your shotguns mechanism that are under some level of compression all the time that don't take a set.

 

[Owen Sparks]

Let me add this: This belief that springs take a set is like a lot of other myths and legends in that it is based in something that USED to be true. Low carbon springs made in blacksmith shops and used in muskets used to have this problem back in the days before the Industrial Revolution. It was generally known that storing a gun cocked for a long time would weaken the spring. Modern spring steel is much more resiliant.

 

[Sport45]

It's a shame gun makers don't use the same material used in automotive valve springs. Those seem to function fine for millions of cycles and can set in a compressed state for decades without loss of function.

But then again, maybe they do....

 

[Effigy]

I'd rather take a chance on having to replace the mag spring than take a chance that my gun is unloaded when I really need it. It's not like a pistol that takes only a second to load.

 

[Virginian]

Maybe some manufacturers do use as good or better alloys as the car manufacturers. I have a few Remingtons from the 60s and 70s, one was a skeet gun for a long time, and all the springs are original and work fine. My 1973 Ruger works fine. A 1960 something High Standard 22 still works well, too.

 

[Carl N. Brown]

I have seen one shotgun tube magazine spring that weakened due to being left loaded for long periods of time. I do suspect that it may have been an improperly tempered spring. A properly tempered spring is worn out by cycling, not by sitting. Still make a point of loading my shotgun 4 rounds in a 5 shot magazine. My other shotgun is a five shot tube plugged to two rounds so even "fully loaded" the spring is not overworked..

 

[catnphx]

I have a few responses:

1) Shotguns have been around for along time and most people that use them for HD keep fully loaded in the tube. If springs were a problem the industry would have either fixed it or we'd be hearing much more about said problem. I've not heard anything on this issue for my 48 years of life nor have I experienced any malfunction because of a weakened spring.

2) If a spring (or any part) wears out you replace it. It's not a big deal. What is a big deal is if you are in an encounter with a BG and you need the extra ammo but don't have it because you didn't want to put pressure on your spring. Doesn't make much sense to me.

3) A gov't drop test will not stop me from keeping one in the chamber ... I'll take my chances.

Obviously, each person makes decisions that are best for them and these are my opinions and decisions for my 590A1.

 

[AJumbo]

Mag springs are relatively inexpensive, and should be replaced periodically. I keep a round chambered in my HD shotgun (no kids in the house), with a full magazine.

 

[swinokur]

Wonder if I need to put my car on jack stands at night to prevent spring set?

 

[wally]

Our home defense shotgun (Winchester 1300 Marine) has sat fully loaded for about 10 years. Wife wanted to shoot it a few weeks ago. No issues. I keep it loaded with 5 2.75" shells and the last one (first one in) is a 3" magnum.

 

[Ironclad]

Wonder if I need to put my car on jack stands at night to prevent spring set?

Nope. but would you leave your half ton pickup loaded with a thousand pounds of bricks for months at a time? It's designed to carry that much, but it probably accelerates suspension wear.

 

[Ironclad]

I have seen one shotgun tube magazine spring that weakened due to being left loaded for long periods of time. I do suspect that it may have been an improperly tempered spring. A properly tempered spring is worn out by cycling, not by sitting. Still make a point of loading my shotgun 4 rounds in a 5 shot magazine.

Wait a second... you understand engineering principals but still trust yourself over the science when something fails? Is that even allowed?

 

[Guns and more]

I guess the same applies to the clips to my 92 as well.

When I was new to THR, I used the term "Clip" and was severely chastised.
I guess I'd seen too many movies.
Now, It's "magazine" for me.

 

[withdrawn34]

I might be wrong, but I think this test is slightly flawed. The dropping muzzle down scenario requires that both the shotgun and the firing pin be moving in the direction of a firing pin strike. Then the gun comes to an abrupt stop while the inertia of the firing pin lets it continue, against the spring, to hit the primer.

This could be tested in reverse, with a sudden movement of the gun and shell smacking the the primer against the firing pin, which would be held momentarily stationary by inertia. However, it would require that the gun be allowed to move, and not be resting against a solid surface like in your test.

Also, this would not cause the hammer to fall, so the only way to test this would be with a primed hull.

Great points. I agree. Ultimately, that particular test did nothing to convince me, since I felt that it probably wasn't truly reproducing the "drop" scenario - as your post points out.