View Full Version : Mossberg 500 disassembly

April 17, 2007, 10:43 PM
I bought a 20" barrel and 7 shot magazine combo for my Mossberg 500. I don't have an owner's manual. Will I need a takedown manual to manage this conversion or is it easy enough to figure out for someone who is mechanically inclined?

April 18, 2007, 12:44 AM
Next, place the safety on and clear the action (make sure it not loaded)
Then the knurled lever in front of trigger guard, depress it and then bring the forearm slowly back to mid-position.
Now turn the magazine cap down to release tension on the barrel and clearing the projecting pin (on mag cap) from the barrel lug.
Pull barrel slowly forward till rear clear the receiver front.
Replace with new barrel and reverse procedure.

chris in va
April 18, 2007, 01:57 AM
He needs to know how to replace the magazine too though. I understand it simply unscrews, but defer that to someone in the know.

April 18, 2007, 03:34 AM
Yup the tube unscrews right off. DO NOT use pliers or anything like that to remove it or attatch the new tube because the tubes are VERY thin walled and will dent and be useless. Do it by hand and no tools.

Gabby Hayes
April 18, 2007, 12:24 PM
You can download Mossberg manuals:

April 18, 2007, 07:33 PM
Thanks guys. Barrel and forend were pretty straight forward. That mag tube though - getting that out is a bear. I shot it with some WD-40 and still haven't gotten it out. Has anyone over had to use a strap wrench on one of these?

April 18, 2007, 09:50 PM
applied at the receiver front will loosen the threadlocker compound and allow removal. Turn a wood dowel to fit ID to prevent collapsing, if using strap wrench

Caution: Some states when hunting only allow 5 shots in mag and MAY not allow extended mag for hunting. Check with your Game officials.

April 18, 2007, 10:40 PM
Well a pair of padded visegrips at the end of the tube where the barrel screws in was able to coax it out without damage. The new magazine is smooth but the old one has two metal bands around it. Both are about one third from each end of the tube. Between one band and the threaded end of the tube there is also a flat piece of steel in the shape of a spring that goes around the barrel but is moveable. Should I be worried about these dissimilarities? Jroth you mentioned thread locker. Do I need to apply some to the new tube? Do you recommend the blue or red threadlocker? No worries, I don't hunt much and I use my Beretta AL-2 for the skeet shooting.

April 18, 2007, 11:01 PM
did you use heat. I'd love to get mine off but can't.

April 18, 2007, 11:22 PM
No heat. I shot it with WD-40 around the threads first. Make sure the WD can actually get to the threads so clean out any gunk that may have accumulated there. I let it set for a minute or so then gave it a couple of good whacks on the receiver, on both sides, with a rubber mallet. Hit it right where the threads attach, but don't hit the tube. Don't be gentle, you wont hurt it. Let it sit for a couple of minutes to let the WD penetrate. Then I whacked it 2 more times and put the visegrips on the very end of the tube and twisted. Voila!

April 19, 2007, 06:45 PM
dang. I've been trying for a year.

April 19, 2007, 07:17 PM
I hadn't shot or cleaned this gun in a REALLY long time, so it might work for you. Let us know how it pans out.

April 19, 2007, 08:56 PM


April 19, 2007, 10:16 PM
CALNRA - thanks for the video it's great. I was able to get it all apart with the manual, but I may need the video to get it all back together. It's all cleaned up now and ready to reassemble. Do I need to put threadlocker on the magazine before I install it?

April 21, 2007, 04:06 AM
you bet. the video is fantastic since it shows you how to line the bolt and the shell carrier up so you can fit the bolt plate on it without cursing anyone's mother, that is the hardest part of the whole ordeal

as far as the mag tube go I think a really heavy torque would do it, although some blue locktite wouldn't be bad(I think it's blue, the non-permanent one). The Mag tube should stay put since there isn't much of a force acting upon it during the operation of the shotgun.

Not trying to say you should abuse your mossberg, but I have two mossbergs, one with 3-4 thousands round through with lots of slugs in there, never cleaned, and one that is my home-defense gun that has seen maybe a few hundred rounds, and they feel exactly the same after I pour some oil into the action of the field gun. They are of the identical basic synthetic model and just keep on working. You shouldn't need to clean the gun too often.

Have fun.

April 25, 2007, 08:19 PM
Mossberg 500 (rebadged as a Westernfield) transformation complete.

Before - 26" C-Lect Choke w/ 5 shot mag

After - 20" Cylinder Choke w/ 7 shot mag and a lot cleaner

Grand total $150 for the kit and shipping via ebay.

I'm thinging about adding a Knoxx Copstock and Synthetic forend but I kinda like the old school riot gun vibe for now. Just needs a recoil pad for sure.

Thanks to the forum for the help especially CALNRA.

BTW how do I get these to post as photos right into my post instead of icons. It would've made for a better before and after. And I apologize for the pic quality - taken in haste.

April 26, 2007, 12:17 PM
Green Loctite, which is for scopes and delicate instruments, is what I use on mag tubes. The blue Loctite usually requires heat to break it and I think it's too strong for the thin walled tubes. The auto box stores usually carry the green but if your in a smaller town it may be an order item.