Magazine Spring for 870 Express

[Homerboy]

I have the 870 Express with the +2 extension factory installed. Last week, it flew off when I was shooting. Tightened it again and fired 15 rounds today. Held together, but while reassembling it after cleaning, the extension will NOT stay on. I have it pefectly lined up, and the barrel clamp is rock solid. When I screw the nut to the tube, it continues to turn until it is off the extension and onto the tube. Give it a tug, and it comes right off. I spent way too much time trying to get it right, so I am chucking the whole thing. I just ordered a new mag spring and mag cap with sling stud. Then i see a mag spring retainer. Didn't need one on the extension, so I look it up in the manual. I see the standard mag cap needs one. The one I got from Midway says it fits the "newer 870 Express". Is there a newer version of the Express? Mine is 3 years old. Do I just pop the retainer into the mag cap, pop in the spring, and screw it in?

 

[dfariswheel]

That's not how you assemble the factory extension:

Put the barrel on the receiver.

Screw the collar onto the gun until it's just snug, then tighten ONE more "click". (You should be able to unscrew the collar with just your fingers).

Insert the magazine spring, then screw the extension on until it just seats against the guns magazine tube. (If you tighten the extension too tight, the stress may make the tubes misalign and the gun may jam. If you don't screw it on until they touch, there will be a gap which will cause jams.)

Install the barrel clamp and snug the screw down tight.

If you want to go to a standard 4 shot gun, buy the OLD STYLE magazine spring retainer and a standard length spring.
Install the spring then press the retainer into the end of the magazine tube.
Make sure the retainer's cupped end faces INTO the magazine.
The Old Style magazine spring retainer is a split steel "Spring cup" device, NOT the long plastic tube type retainer as used on the standard magazine Express models.

 

[Homerboy]

So I have to unscrew the barrel clamp and seperate the extension from the barrel everytime I clean it? Then remove the collar from the extesnion, attach it to the mag tube, then thread the extension onto it? Then clamp it to the barrel?

 

[swampboy]

So I have to unscrew the barrel clamp and seperate the extension from the barrel everytime I clean it? Then remove the collar from the extesnion, attach it to the mag tube, then thread the extension onto it? Then clamp it to the barrel?

Yep. That's what I do. dfariswheel hits all the main points. Follow his instructions & you should have no more problems.

 

[Homerboy]

Eh, I'll give it a try, but it sounds like a lot of trouble just to clean a barrel! My range only allows 3 shots anyway, so I'm thinking I'm gonna go to the 4 round capacity.

 

[swampboy]

Eh, I'll give it a try, but it sounds like a lot of trouble just to clean a barrel! My range only allows 3 shots anyway, so I'm thinking I'm gonna go to the 4 round capacity.

Do what you will, but in my opinion, you don't need to take it apart very often. At all. I've got an 870 in that configuration and here's what I do to clean it. Rack it open, grab a bore snake or Otis setup or a hunk of T-shirt tied to a string and go to town on the bore. Hose the action out with some brake cleaner, run an old toothbrush around in there if it makes you feel better, re-lube and you're good to go. I've gone months-and-months with countless rounds fired using nothing but this method. Once every 3.265 eons, I'll completely disassemble and clean everything, including the trigger group and inside of the mag tube.

Seriously, with a working shotgun, "clean enough" is clean enough. We ain't talkin' 'bout no match-grade target rifle here. That's just my NSHO.

 

[Homerboy]

Yeah, but I'm a clean freak. I shot 15 rounds yesterday, and spent over an hour cleaning it. The rest of the shotgun takes no time at all, but the barrel takes some time. Had it soaking in Hoppes for an hour and used the tornado brush. I run a boresnake through every gun I have after the cleaning as a final wipe.

 

[Snarlingiron]

Had it soaking in Hoppes for an hour and used the tornado brush.

For 15 rounds?

Dood.

I don't spend that much time cleaning the entire gun after 500 rounds. I can have the barrel cleaner'n a Safeway chittlin' in about 10 minutes.

 

[Homerboy]

What do you do? I soak the barrel in Hoppes, hit it with the brush, then follow with patches until they are clean. Funny thing is that I can get a clean patch, the I hit it again with the brush, then send another patch down there and it comes out with black. I've used Hoppes #9, Hoppes Copper Solvent, Hoppes Elite Cleaner, SLIP 200, etc.

 

[dfariswheel]

Funny thing is that I can get a clean patch, the I hit it again with the brush, then send another patch down there and it comes out with black.

The solvent is reacting with the residue left by the bore brush. Whenever you run a bore brush through a bore, it leaves a coating of bronze residue.
A solvent soaked patch lifts and removes that residue, making the patch dirty.

I suspect Homerboy's shotgun is going to be in better condition in 20 years than the guns that don't get cleaned as well.
I have several guns I've owned for over 30 years and they still look like new. That's because I too am a "clean freak".

 

[swampboy]

dfariswheel wrote:

That's because I too am a "clean freak".

Nobody will ever accuse me of being that. All my vehicles have clean oil/fluids on the inside, but the outside is usually a little dingy. I actually had a neighbor years ago who regularly waxed his LAWN MOWER Well, it WAS a John Deere........