mag extensions once again

[proven]

i did a lot of research before i added the wilson mag extension to my 870. i'vee been happy with it so far but have some questions about reliability or lack there of.

it seems that most people are of the thought that a standard mag tube is more reliable. why?? the extension is essentially just the same design only longer. is it because of the added pressure on the first round inserted due to a higher powered spring being compressed?? i remember hearing of a shell's crimp being split and the round jamming in the tube at gunsite, but IIRC, that was due to a defective metal follower.

i can understand the school of thought that it could be bent or dented and cause problems. honestly, the wilson extension is built pretty darn tuff and the sling mount design is what sets them apart from the others IMO. the mount sits ahead of the threads and is comformed snugly to the bbl. its seems to me that if it were dropped on the mag tube, the sling mount would prevent major stress from being applied to the threads, which seems to be the weakest point. now if something slipped over the end of the tube and pulled down away from the bbl, there might be a problem. i guess that is where the bbl clamp comes in, along with reducing vibration.

sorry to bring this up again, but i'm interested in first hand accounts of a mag extension malfuntioning, and the cause behind such.

any comments or opinions are welcome

brian

 

[dfariswheel]

My experience shows two possible problems with mag extensions.

First, while not limited to extended magazines, is the problem of shot sell compression.
Most people are concerned about guns kept loaded for long periods loosing magazine spring tension.

In fact, the real problem is shell compression.
When plastic shotgun shells were introduced, it was noticed that plastic shells left in a magazine for long periods developed bulges in the case.
This bulge appears between the shell head and the shot column.

This is due to spring pressure on the shells causing the plastic casing to slightly collapse, causing the bulge. This bulge can cause failures to feed.

While shells can bulge in standard magazines, it appears to be worse in extended magazines, probably due to increased spring pressure in the longer tube and strong spring.

The second problem is bending or knocking the extension off the gun's magazine tube.
While most extensions are very strong, the tube they're screwed onto is still a fairly thin tube, further weakened by the deep, coarse threads.

If the extension gets a bump, the extension can be bent, or even knocked completely off the gun.
In most cases I've seen, it's the gun's tube that suffers the damage, not the extension.
This puts the gun out of service, and requires a trip back to Remington for a replacement tube and a refinish of the receiver.

Other potential problems center around the joint where the gun's tube and the extension come together.

If either tube is out of round, screwed together so tightly pressure causes them to mis-align, or if there is a gap between them, shells can "hang up" at the joint.

It's been my experience that the major problem of shell bulge is the most common, and this can be eliminated by buying good quality American shells, which seem to be made of thicker or stronger plastic, and by shooting up shells that are in the tube for any longer period of time, BEFORE the shells start to bulge.

The "fix" for the bent or knocked off extension is simply to add a barrel clamp to the extension to stabilize and reinforce it.
When you get down to it, there is no real reason NOT to use a clamp, and the added security is worth any possible benefit to not using one.

The problem of tube misalignment can be eliminated by assembling the Remington factory extension properly, and by carefully inspecting other brands of extensions to insure proper manufacture by the factory.

 

[loudernhel]

I'm NOT trying to start a remmy vs mossy argument here, but one of the reasons I wound up with a Mossberg 590 is that it has a eight round mag that is all one piece. No extension to worry about.

But I think dfariswheel hit it on the head: properly install the mag tube with a clamp, buy good ammo and rotate ammo often.

Might also help to download by a round or two as well.

 

[Dave McCracken]

The HD 870 here has a two shot extension,and the mag holds 5 as SOP. No bulges, but I rotate ammo regularly.

When I was with the MD DOC, we found ammo developed bulges in a fully loaded mag in a couple months. We called it telescoping. Loading one less than capacity slows the process enormously.

 

[VG]

Or, one could ask, when has there ever been a case when a homeowner -lawfully defending himself or his family - had to fire more than five rounds?

There's a lot of tinkering with "tactical" shotguns here, not surprising for an enthusiasts forum. There is much less discussion of - as my friend highlights the security hierarchy - "lights, locks, dogs, guns."

Are there real world case studies that show how 8 rounds solved a problem that 5 would not? One FBI study I saw referenced said that the "average" gunfight had three rounds fired in less than four seconds at distances of 7 to 10 feet.

I note from a thread here or on shotgunworld.com that a lot of LEA use plain old Remington 870 Wingmasters, replacing parts as required during maintenance. Few departments have the kind of tricked-out weapons that some people have here, for cost, training, and effectiveness considerations.

I took my recently acquired Remington to the range last weekend, and after seeing what the target and target frame looked like after round of either 00 buck or #4 (Federal Tactical 00 and Speer Lawman#4), I don't see the need for any magazine extension - which also makes the gun heavier and increases the swing weight.

 

[444]

I remember Louis Awerbuck had a couple things against magazine tube extensions but I only remember one and that was problems caused by the magazine tube extension not being straight: either from the factory or because it got bent.
Personally, I like the feel of the gun a lot better without the extension tube. But, I just put an extension on my main 870 just because it is a PITA not to have it. I have taken two defensive shotgun classes with that gun without an extension and I kinda wished I had an extension. On the other hand, I was kinda glad I didn't. On the one hand, obviously you have to reload the gun more often with the short tube. But, at the same time, you get REAL tired, holding that gun at the low ready and more weight is worse. I also tried a couple "action" type matches with this same shotgun and was at a severe disadvantage because of the short tube. In most cases though I was competing against true "gamers" who were using 26"-28" barrels with 10 shot extensions so I guess it wouldn't have really mattered whether I had an extension or not. I am getting ready to take another shotgun class with Louis at Denny Hansen's range in about two weeks, so I put on the extension for the class. I will see if I leave it on after I try it out in the lcass.
Bottom line, I don't think any of this stuff matters on a home defense shotgun. Weight isn't an issue. And, I don't think that having the extra rounds are an issue for the homeowner. A situation where the extra shells would be nessessary would be pretty hard to imagine. But, you can never have too much ammo.
" i remember hearing of a shell's crimp being split and the round jamming in the tube at gunsite, but IIRC, that was due to a defective metal follower."
That was me, in my Gunsite 260 class. As you say, the problem had nothing to due with a magazine extension. The problem also wasn't a shell splitting: it was the business end of a shell being hammer into the follower resulting in the shell being stuck to the follower.

 

[proven]

444

if you don't mind me asking, do you use the mag/bbl clamp with your extension??

also, give us an update after your class as to how the mag extension worked for you.


thanks
brian

 

[Fred Fuller]

proven,

I have used magazine extensions on 870s since the late 1970s with no problems to report. I started using Choates and switched to TacStars and Wilsons. I have never used a factory Remington extension.

That said, I do not make it a habit to leave shotguns fully loaded. I have long known of the problem with shotgun shells developing bulges if left in fully loaded magazines, and clearing that sort of jam can be--- not fun. The advantage I see of shotgun magazine extensions is to allow a magazine to be loaded to normal capacity (4 rounds) with 'slack' still in the magazine spring, plus room to top off the magazine with a different kind of ammo if the situation requires it.

My personal preference is for an 18" barrel with a two round extension. I _always_ use clamps (save on long recoil mechanism autoloaders) and usually locate them near the back of the extension close to the joint with the magazine tube. I also use the clamp as the base for the front sling swivel.

My wife, however, is a petite lady without huge amounts of arm strength. Thus our two 'house gun' 870s are configured to fit her. They have 20" smoothbore barrels with factory rifle sight bases fitteed with tritium inserts, stocks cut to 12 1/2" lenght of pull, full length field style forearms, detachable lights (M3s) and 4- round SideSaddles. They do not have magazine extensions and thus are loaded with only three rounds (two loads of low recoil 00 buck and one round of birdshot), the SideSaddles carry two more rounds of low recoil 00 and two reduced recoil 1 oz. slugs.

Good extensions properly mounted and properly maintained should be as reliable as the original factory magazine setup. Proper maintenance includes proper cleaning, lubrication and inspection and replacing magazine springs with the proper replacement when needed (I use Wolff). The only problems I have seen with magazine extensions came from improperly removed dimples in Express models, from 'gee whiz' magazine followers or from using old, tired, kinked or improperly sized magazine springs.

The reported worry over shell stops not being able to withstand the pressure of extra rounds and stronger springs has been around for a long long time. Yet magazines have been extended on tubular magazine slide action shotguns for over a century- the earliest I know of was the Winchester Model 1897. Any number of market hunters and old time lawmen had extensions fitted on these guns, and many of them increased the ammo capacity of the gun up to 11 rounds.

Remington began seriously considering magazine extensions for the 870 in response to the conflict in Vietnam, starting their Military and Police Shotgun Development Program in the early 1960s. Various experiments were carried out and some new patents issued covering various components of the new concepts in fighting shotguns. High on the list of desires for a fighting shotgun was increased amunition capacity, and magazine extensions were the easiest answer. A number of 870s had been purchased by the British in 1954 for use in fighting the insurgency in Malaya, and an extensive report on the use of combat shotguns was produced aftter the fighting was over. This study came to be influential in the production of different features from different designers as the American involvement in Southeast Asia became more extensive.

Magazine extensions have been around for a long time and have been a part of Remington's design efforts for the 870 since the 1960s. Properly installing a good aftermarket extension should cause no degradation in reliability. Simply put, take care of your shotgun's tubular magazine, with or without an extension, and it will take care of you.

lpl/nc

 

[sm]

If I may ask...

Dave, Lee, 444, SapperLeader...Denny....whomever...

In regard to the mag follower , the old 870 used a metal one, the current one is orange plastic, from my experience I have not had problems with these "original " designs. Many other shotguns use a similar design. I have heard problems exist with the smaller diameter, and shape of "newer" aftermarket designs.

What say Awerbuck , and what has been experiences in real world applications?

My personal thinking runs to original metal, and same - though orange, being less prone to fit inside crimp of pellet loads, and starting a bulge.

Personally , for my needs, I don't use a mag extension. Reliability and weight considerations.

I have used/ kept the "increased" mag count ....from factory . Ithaca 37 , 870s , the Police versions.

 

[Fred Fuller]

Steve,

I haven't heard/read any comments by Awerbuck specifically regarding followers. He may have opinions, I just am not familiar with them.

I too liked the old style Remington metal followers. I think they were stamped, not machined, but it makes little practical difference because they are no longer in production. You can (or could) get machined followers from Brownells and from Uncle Hans Vang if you want one. I am not a great fan of the current plastic followers, but I still use them- I have never heard of one failing by breaking (as Choate used to threaten in its literature, plugging its own solid cast followers). But I have seen a lot of them in used guns that were so rough as to threaten function. Of course the plastic follower was rough because the mag tube was full of grit and sand or had problems with rust from lack of maintenance, thus compounding the feeding problems.

For guns with extensions I like the green 'short tail' follower that Wilson sells, for standard magazine guns I use whatever follower came in the gun. I go over a lot of "Cinderella" 870s in the stores, and won't get one with dimples any more no matter how good a buy it is. There are too many older guns around to have to mess with dimples. The 870 Express at hand right now (in the corner by the computer desk) is the 'turkey gun' I got recently (21" VR barrel, RemChokes, double beads, sling swivls, $145 out the door). It has the issue black plastic follower with the bump in the middle along with the spring-steel magazine spring retainer. I looked at the inside of the mag tube in the store before I bought it, had the follower been chewed up it would have been a reason to inspect a lot closer and likely turn the gun down. This one has no mag extension and likely won't have one, but the lack of dimples makes adding one easy. It might not always be me making the decision and there are a few extra 2- and 3-shot extensions in the parts box.

I confess not understanding the insistence a lot of people place these days on having absolutely bulletproof parts in absolutely every piece of personal gear. _Anything_ can break if mishandled or abused enough, and most shooters are never going to approach the wearout/breaking point of any good modern firearm. Yet they insist every detail has to be built like Ahhhnold. I just don't get it. The worst most of these folks face is a home invasion, maybe once in five lifetimes are the odds I'd guess on that. A couple of my friends are armorers for the specops folks, and I know for a fact the secret squirrel operators themselves are not as paranoid about their hardware as a lot of folks whose worst experience is a flat tire on the way to their desk job. Beats me...

What I _do_ see happen a lot is people taking a perfectly functional firearm and then modifying it to extraordinary degrees, and bolting on all manner of bells and whistles until the poor beastie simply ceases to run reliably. Then of course it's the manufacturer's fault, soandso builds crap, mine never has run right blahblahblah. Granted there are a few lemons in any mass produced item, but a lot more lemons are made by owners in the firearms world than are born on assembly lines.

Re. any of the above, YMMV- worth exactly what you paid for it.

lpl/nc

 

[proven]

great posts Lee Lapin.

thanks much


brian

 

[greyeyezz]

My experience with a Choate 3 shot extension on my 870 was an occasional bind using the stock plastic follower, probably getting hung up at the junction. No more spring pressure on the rounds, a very bad thing. My theory was the plastic follower would tilt slightly because of its short length. I went to a longer steel follower from Quality Parts and no more binding, the plastic follower went in the ????-can.

I now have a Wilson 2 shot, 7 rds total, with the long green follower, its been 100%, less muzzle heavy too.

 

[9mmMike]

I have factory plus three extensions on all my Remington's (870's & 1100) with the exception of the 16 ga. WM (wife's) and 20 ga. 1100 Special Field (wife's) and one of the 870's in 12 ga. that is actually mine.
I have never had any trouble with them. They all use clamps and the mag springs are of various lengths yet have never given me trouble. I even measured them once (couldn't sleep that night) and posted the info on TFL.
Point is, I have not had to do anything special with mine. I clean my guns after every shoot and that's a lot. The guns are pulled apart every time so the extensions go on and off every time. No troubles.
I had one that seemed like the threads were slightly off though. I bought them all used and it was one of the MM extensions that was a little odd. I swapped the threaded nuts (factory extensions are all two pieces) and it worked fine.
My HD gun is downloaded by one and I shoot the mag every once in a great while. I have not noticed any bulging or feed problems. The HD ammo is all Federal "tactical" LE stuff - 00, 000, and slugs.
I currently use all aftermarket followers, some Wilson, some Vang, some Brownells stainless. I had a Wilson that hung up but it was in an x-dimple gun and I worked a little harder to smooth it up and it was fine after that, I may have also swapped to the Vang follower. I don't remember.
As far as handling goes, the extensions certainly heavier, especially with a full mag but they are not much of a problem if you only load four and it is always nice to have that extra room in the mag if you needed it.
What does this mean? Beats me.
Mike

 

[sm]

Lee , Thank you .

dfarris - as always good to see you post . Hope is all is well with you and yours sir.

444....I was curious on Awerbuck's take - thank you.

I have not had a problem with the OLD style followers. I have yet to encounter a problem with the Factory orange ones.

I have seen the problems with some other makes, the follower fits inside the crimp, add extended storage times - or - the recoil of repetititve heavy loads.

Part of this falls into "inspection and maintenance" , I mean one should rotate ammo and inspect. IME the factory metal followers, even loaded up for extended times, never caused a problem, I rotated ammo...

A few folks have gone to the expense to have a machinist make one like the original.

Makes one wonder if perhaps going back to a card instead of 8 point crimp might be a bit of insurance....

I and some others are running some guns stock and see how they hold up. So far , so good. Some are ON purpose being run through the mill over and beyond "normal and expected use". And yeah - we are not fans of plastic...

Just thinking out loud. WE all learn .

Thanks all....

 

[Dave McCracken]

A couple things....

Mag extensions are not essential. As was said, few crises show up that 6 or 7 rounds of shotgun ammo will handle but 4 will not. T'were Wonderful Wife a shotgunner, the HD one here would not have one, for WW is a Pixie and extensions put too much weight forward for easy manipulation by wee folk. She prefers her Colt.

A stock 870 right from the box is a fearsome and reliable close range weapon. All the bells and whistles add little to the effectiveness.

A shotgun is merely a device to direct a cloud or slouds of shot(Or a slug) to a target and to do so comfortably to the shooter. Any accessory or modification that aids that is worthy. Anything else is just Bling.

 

[SapperLeader]

I have two 870s and both are set up for home defense roles. The one is my main hd gun and is the one I used in my recent tactical shotgun one course with Awerbuck. It is a synthetic HD model and came with the +2 extension and clamp already on the gun. The other gun has no extension, just the 4 round tube with dimples. Both models came with the factory orange follower, and I have had zero problems with the guns while shooting. The 870 hd with the extension though, did run into some small troubles with loading drills during a recent shotgun course. When I failed to push a shell all the way into the tube, I was only able to load five rounds in a six round tube due to the follower binding the spring. I would then fire one or two shells, and would regain the ability to load to full capacity. Not a huge deal, and most of the time I just pushed the shell in properly, but it was one I wanted to rectify. Another guy in the class had a similiar problem with a jury rigged mag extension, orange follower and no clamp, but his would only let him load two or three rounds.
Awerbucks recommondation was to use one of an extended followers, but mentioned no preference on which one to use. He only said use the factory orange with a standard tube, and get a extended follower with a extended mag tube. I purchased a wilson green extended follower, because I liked the raised button in the middle of the shell. I havent installed it yet do to wanting to take the gun to the range for testing purpouses when I do the installation. Ill let everyone know how it goes once I do.
Is the button in the middle of the follower going to cause problems with hitting shells? Is this what causes bulged shells? As for the shell bulging problem, this is the first Ive heard of this. I recently started loading my tube to full capacity(last 5 weeks), and havent seen any bulges in ammo yet. Is this more of a problem in guns being jostled around in cars or while the gun is being fired? Im not sure what I should be looking for on the shells.

 

[dfariswheel]

Shot shell compression isn't caused by the follower shape, it's caused by spring pressure.

When you take a relatively soft tube like a plastic shell and subject it to spring pressure over a period of time, the plastic tends to compress, causing a bulge.

The bulge looks like a rather narrow, ring-like bulge below the shot area, and above the steel shell head.

Tellingly, the bulge is between the steel shell head and the shot column.

The shot reinforces the shell in that area, and the bulge forms in the unsupported area lower down.

If the follower were to have any effect on this, the bulge or deformation would be near the case mouth.

Factors that cause compression are:
Spring pressure.
Time. (How long you leave the shells in the magazine.
Shell construction. (Cheap shells, especially foreign brands seem to be weaker).
An added factor is the police practice of putting shotguns into upright shotgun racks in police cars. The constant bumping and jarring caused by the car tends to increase bulging.

The best way to eliminate the problem is to use high-grade American shells, and to shoot up the shells loaded in the magazine fairly often.

NOTE: rotating the shells is NOT effective. Once a shell does start to bulge, it will NOT "recover" and un-bulge. Once the shell is replaced in the magazine it immediately resumes bulging, more or less where it left off.

 

[444]

"....give us an update after your class as to how the mag extension worked for you."
I can give you that information right now. The class was cancelled. After posting notice of the class on several boards, they were only able to get two people to actually follow through with it. The other internet/armchair warriors had nothing but excuses why they would rather watch TV than train with perhaps the best defensive shotgunner out there. Typical.

"I confess not understanding the insistence a lot of people place these days on having absolutely bulletproof parts in absolutely every piece of personal gear."
The concept is very simple. Gun owners love gadgets and gear. They love to read about, discuss, and think about gear. As a result, they spend a lot of money and time buying gear that is probably unnessessary. I think at least a little bit of this comes from spending far more time playing with gear rather than shooting. This causes people to buy a lot of gear that is not practical, or gear that is totally unnessessary but they don't know any better because they don't have enough experience with the gun. Some of this stuff is a definite upgrade to the existing platform. It might not be needed, but it is better than the part that was on there. I see nothing wrong with modifications like that.

 

[AirPower]

Is the Remington factory mag extension best solution and most robust for 870?

Also, is Remington factory extension +2 or +3, or both?

 

[9mmMike]

I would not say that the factory is more robust. I've seen a few, the Wilson and Vang Comp ones come to mind, that are certainly beefier.
I like the factory extensions because of the factory clamp and two piece design. They fit well and do their job. They also look cooler!
The factory extensions come in +2 or +3 flavors. My are all +3 because I use 20" barrels.
The best solution? Too subjective for me to answer but I do like them.
Mike