View Full Version : mossbeg 500 18 in

December 7, 2010, 03:53 AM
hey yall i just picked up the home defense 18 in barrel for my mossey 500.... when i got home i noticed that it wont fit on the standard magazine tube.... is it ment for the 8 shot tube???

Sportsman 12
December 7, 2010, 09:59 AM
Define how it doesn't fit?

December 7, 2010, 10:02 AM
I, too, have a Mossberg 500 which I fitted with an 18-inch barrel. Mine fit. If the takedown screw is too far away from the magazine, then you may be right that is is for the 8-shot

The distance from the end of the barrel's flange that slides into the receiver to the inside edge of the flange holding the takedown screw is 15-13/16 inches on my 18-inch barrel.

Smitty in CT
December 7, 2010, 10:13 AM
If it's an 18-1/2" barrel it's made for the standard 5 shot mag tube....

If it's a 20" barrel, then it's made for the 7 shot mag tube....

What is stamped on the barrel???

December 7, 2010, 10:41 AM
Measure the distance from barrel tip to lug, I will do the same on mine...

The action is open when installing correct? "Capn' She won't go no further..."


December 7, 2010, 11:53 AM
Set it next to the old barrel---if the lug spacings are even remotely close--I'd have to say operator error.

December 7, 2010, 06:07 PM
Take a look at this barrel chart. I aam newbie to this but have been figgering out what barrels I can add to what, and I don't think there is a Mossberg 18" barrel. There is an 18 1/2" and a 20". BTW there are also Maverick 88 barrles that will fit Mossbergs. I am guessing you got a 20" barrel for a 535 Mossberg security.


December 7, 2010, 07:46 PM
18 1/2 is called the 18.

Sportsman 12
December 8, 2010, 10:37 AM
Pump it half way, line it up. There will be a 1/8 or so gap after you tighten the screw.

If you have the 7 + 1 shotgun or barrel, it won't even be close. More like 5inches difference.

May just be operator error in installing.