I have long been a fan of the Mossberg 500 shotgun. Readers may recall that back in early January I had a perplexing, intermittent failure-to-fire problem with an almost-new Maverick 88 that I picked up for a song (probably because the owner knew that it had problems but didn't tell me). For the uninitiated, the Maverick 88 is a less costly to manufacture, simplified version of the Mossberg 500 shotgun. As I wrote at the time:
Some months ago I got an inexpensive used Maverick 88 for my daughters' apartment at college. Having stripped the thing, the trigger group (indeed, the entire weapon) seems near new with little usage, but right now, even with a variety of ammo, it is failing to fire 3 times out of 20. If I remember right from my old Mossberg 500, the rear of the firing pin ought to be able to be depressed (using your thumb) by pressing on the back so that you can, without pain, make the business end of the firing pin peak out the front of the bolt face. Either the pin is binding or the spring is too stiff because I can't do it without pushing it against a solid object. Anybody else had this problem? What fix did you use?
That problem has now been solved. As I suspected at the time, the factory firing pin spring was far too stiff. In fact, even calling it a "spring" may be a misrepresentation. Rarely have I ever seen a spring less springy. Replacing the spring turned it into a 100% weapon.
I also did one other thing at the time to upgrade the Maverick -- I replaced the cheap Maverick slide bar & forend assembly (which is made all in one piece as seen above) with an older, stronger and much more reliable Mossberg 500 slide tube & bar assembly. (See below, without forend.)
My gunsmith had an extra one (minus fore grip) laying around and he charged me just $10.00 for it. We went ahead and swapped it out after replacing the spring, and even though it had no fore grip on it, it still worked perfectly. Now all I have to do is find a new Mossberg 500 foregrip that I like.