• Mossberg Owners is in the process of upgrading the software. Please bear with us while we transition to the new look and new upgraded software.

Has anyone actually put a Maverick 88 Trigger Group in a 590 Shockwave?

Has anyone done it to verify that it really is compatible?

Having the obvious safety where it "wants to be" is the issue here.

But has anyone actually done it? Don't want to buy one, only to find it is not compatible.
 
Guess the first question would be why would you want to do this?

Beyond that, "theoretically" you should be able to swap the trigger group; however, i don't see how the original tang safety will function without the original connector?

But IMO, you're building in a potentially hazardous situation for anyone who picks up the gun and based on their training and longtime use, believes the gun is safe when they engage the Shockwave tang safety. Certainly, couldn't sell the gun in this configurtion.

Maybe someone here has actual experience on swapping trigger groups. Doubt it but you should discuss with Mossberg service before attempting a swap. They are the experts! Let us know what they recommend.

If you want a Shockwave type weapon with a Remington style trigger guard button safety why not simply sell the Mossberg and buy a TAC 14?

Regards
 
When fitting this, which keeps the shockwave longer than 26.5 inches (actually makes it a little longer than the bird's head grip), the tang safety is "not within easy reach".
https://blackhawk.com/knoxx-breachers-grip-gen-iii/

The recoil reduction is a significant advantage, so the swapping of the trigger group is one solution to the awkward safety location, for those of us who were taught that the safety is on until one intends to shoot, and is immediately one once again after shooting.

But I did not ask for opinions on WHY I might want to do this, or for alternative options one might consider, I asked if anyone has actually tried the replacement, and verified that it is swappable.
Clearly, one would remove the tang safety switch if fitting the Maverick trigger group, so the concern about the safety of the safety is misplaced. One would see the gaping hole where the safety once was, and this should be sufficient.
 
I myself have not swapped trigger groups,,,,But if I remember right a few years ago there was a member here that did it. He took out the 500A trigger group and safety from a 500A and slipped in a Mav88 trigger group with no problems.
He was searching for ideas how to close up the hole in the receiver from the old safety. His reason for swapping them was the first trigger group broke and he had a spare Mav for parts.
Keep us posted.
 
You may not have asked for opinions, but you are sure to get them. This isn't the first time where you've been mucking with the gun buying aftermarket parts and it's giving you problems and you come here asking for guidance. No one here is going to tell you to redesign the gun so you can use aftermarket part A, B, or C. I'm not sure if you're being for real or trolling at this point.

But OK. I'll see how far this goes.

The tang safety isn't within easy reach. Of the aftermarket grip that you're wanting to use. Gotcha.

The non-lit go gauge follower isn't working right.

I bet it's not as easy to release the slide lock with a grip either. Or if it is, you'd probably have to turn the gun somewhat sideways and off target to use it. You going to move that too?

I'm sure that changing parts out to stuff in the wrong models would surely void any nuance of warranty that you may have as well. I know I wouldn't touch a gun that had been altered as much if I were the manufacturer. And no self respecting FFL is going to take it in for a trade or sale either.

I bet even Chevy wouldn't warranty an impala with a hummer motor in it either, despite both being produced by general motors.
 
Just a helpful hint to the OP.

It would be extremely helpful if you fully described in detail what you were trying to accomplish up front in your original post vice adding something totally different after the fact.

While I know you're new to the forum and certainly welcome, it's important to ask complete questions up front and respect the feedback members provide. We have decades of experience on this forum not only with the Mossberg products but with a broad spectrum of brands. There are members here who have three to five decades of experience in law enforcement and in the military. Most are absolutely willing to help anyone and everyone as long as the help is appreciated and accepted in kind. Enough said.

Please take this advice in the positive spirit which it's given. It's a learning process for all.

Again, welcome to the forum and hope you will continue to participate. And good luck with your project

Regards
 
Modifying a gun in that way may work against you if you end up in court. Just something to think about if using the gun for home/self defense.

That said, I have not seen it done.
 
Thanks for the helpful advice in dealing with people Ernst, but I thought I did describe in detail what my goal was. I will add more detail, as so far, I've gotten nothing but flak and insults, with only ONE account of swapping, answering my purely technical question.

I have a 5' 6" 118 lb wife. Covid has occasionally left her alone at our country place when I have been forced to travel, and it looks like we are not going back to the City anytime soon. She expressed concern, so I bought her a Shockwave, as it was the smallest and lightest legal Not-A-Shotgun one can find, and it was a Mossberg, not a "Freedom Group / Cerberus Capital Management" piss-poor QA product.

But... recoil. So, looking at options, the Knoxx Breachers Grip Gen III seemed best.
But, it makes the safety.... awkward, and my practice for a solid 50+ years of shooting shotguns has always been to consistently make the sounds "Click, Boom, Rack, Rack" in that precise order, so the safety stays on until weapon is being aimed at target.
So.... move the safety.
And, lo and behold, the Maverick 88 puts the safety on the trigger group exactly where it "should be" for the Knoxx grip.

Do I care about resale? No! The old trigger group can slide back in any time for resale, just as the birds-head grip can bolt back on.
Do I care about warranty? No! See above, the gun can go back to "factory stock" in 10 minutes, as I can disassemble and clean a Mossberg in my sleep by now.
Do I care about "court"? No! If the gun is ever used, there will be a dead person on the floor, and a wife who fired only because she was unable to run away. We are not about to use a gun to protect "stuff".
Do I care about the "hole" where the tang safety went? No! I can 3D-print a smooth flush black cover plate to fill the depression, and put a nut and washer inside the receiver to keep it in place. Again, the stock safety can bolt back in any time.
Do I care about staying short AND legal? Yes! Why else would I pay the premium for a Shockwave, when I could have just started out with a far less expensive, and "otherwise identical" Maverick?

So, that was my question - I'd rather not spend yet another $30 or so on a Maverick Trigger group, and I figured that I couldn't be the first to come to the obvious conclusion that a Shockwave might need some recoil reduction, or the only guy to have a shawty who is a shorty.

I'm not a cheapskate here, I've already added the usual fittings one wants in a "home defense" weapon: Streamlight TL Racker, Crimson Trace LS-250G green saddle laser, composite heat shield, and I even drilled and tapped the heat shield to move the bead onto the heat shield "just because". Oh yeah, and the Delrin follower... why? Because a physicist like me looks at a stamped sheet-metal component with a spring behind it, and thinks "that sucks". I've had Delrin followers since they were first offered in my other Mossberg pump, feels much nicer.

What is my wife going to actually DO? She'll shoot at ground targets with this every other month or so to keep skilled, out at the Hudson Farm complex in NJ, and maybe, just maybe, she'll do some skeet shooting now and again with break-open double-barreled "real shotguns", either with me, or one of the all-ladies gangs that have formed out there. But over the short term, or if she is not so social about shooting, recoil is the thing that will limit her willingness to practice shooting.

But the shockwave is a single-purpose weapon, and will only be used under a very stressful scenario when lots of s**t has unexpectedly gone lateral, so lots of practice will be needed, and every possible "ease of use" factor needs to be addressed.

I do hope this helps the far more experienced and far wiser subscribers to this interwebnet thingy who were so helpful with their many suggestions and comments to understand exactly where I am coming from.
 
After all is said and done swap it out and you can fill the hole with a "hole plug".
hole plug..jpg
 
Mr. Fischer, I don’t know jack about Delrin, trigger groups or followers, and I’m SURE your wife has far more shotgunning experience than I do,but I have shot my Shockwave and nothing is gonna tame the recoil except the load and the grip technique. Because both Mossbergs I’ve owned had the top mount safety, I just got used to them, like you did with the 88 configuration. I have the laser saddle on mine also and was thinking of getting the Shockwave brand fore end/ heat shield so I could grab the whole dang gun to control the kick up. (something about an explosion and a bunch of steel balls a 32nd of an inch from my fingers is, um, disquieting lol) But they said that was a no go with the saddle, blocking the beam with the heat shield. I have a mental picture of a custom shield that doesn’t mess with the beam and also allows the ambidextrous grip my home defense scenario requires. I would be interested to see a pic of your work around.
 
James, couple of additional thoughts for your consideration.

Apparent Shockwave recoil is a combination of things including the type of ammo you choose. Your shockwave, being a pump, will run on about anything from these new mini shells, low recoil full size shells, regular power 2 3/4 shells and up to full powered 3 inch magnum bear loads. You didn't mention what type of ammo your wife is planning to keep loaded but that selection likely has more impact on felt recoil than anything else you do.

Secondly, you might consider the dynamics of the two grips. Short barreled shotguns traditionally for years had "pistol" grips which when fired put the recoil force directly into your wrist. And the wrist, being a weak point in your arm, suffered pain plus many folks, especially those with weaker wrists, had problems controlling the muzzle rise. The advent of the "birdhead" grip changed the total dynamic and impact of recoil on the body. The shockwave recoil move straight through your wrist and down your forearm which actually makes shooting a shockwave reasonable pleasent.

My situation is totally different from yours in that my biggest threat is bears and with a shockwave birdheads grip I can shoot Brenneke 3 inch Black Magic Magnum Bear Loads. And yes, the recoil is excessive but something I'd not do with a pistol grip short barreled shotgun.

Suggest you try several types of ammo to test the differences in recoil and patterning of the shot before selecting your everyday HD load.

Again, welcome to the forum and good luck with your project. Please show us a final configuration picture.

Regards
 
Last edited:
If the lawyers have left the room, I'd like to mention that as a gun eNthUsiasT, I am also curious about the difference in the 88 vs 500 trigger groups & safeties. We're all big boys and girls here so I think we recognize the "danger" such a swap would present and will act or not act accordingly... :)
 
But they said that was a no go with the saddle, blocking the beam with the heat shield.

I have a heat shield on a Shockwave, and it does not block the beam of a CT-LS250. It is the very common cheap polymer type sold for Mossbery 500/590, and while one needs to elongate the holes in the outward direction a few mm in the bottom "clamp" to accommodate the thick barrel of the shockwave, and allow the screws to thread (1/2" screws are needed here, as the short ones that come with the heat shield will be too short) it otherwise works and looks fine.

Now, I went overboard (of course) and installed a #5-40 set screw sticking up out of the in the threaded hole where the muzzle bead was, and partly drilled into the underside of the heat shield so that it would fit over the protruding set screw, so that the heat shield would have something more than just friction to keep it from twisting/rotating around the barrel. I also drilled and tapped the heat shield itself for the same bead removed from the barrel, moving the bead slightly further towards the muzzle to avoid the aforementioned set-screw. Blue Loctite on both the setscrew and the bead threads, of course - you don't want that setscrew protruding down into the barrel. (I need to consider epoxy for the metal bead threaded into the polymer heat shield, but the Loctite seems ok.)

So, go for it - worked for me!
 
Last edited:
James, couple of additional thoughts for your consideration.
Apparent Shockwave recoil is a combination of things including the type of ammo you choose....

Yes, of course, but to be blunt - the sole intent of this weapon is to be used once - when running is not possible, and my wife has no other option. So, while I could handload (or just buy if they ever get them back in stock!) some "Federal Shorty Shells" with a limited number of OO buck pellets, and create a "reduced recoil shell", I think it would be better if she was able to shoot a normal OO shell, given that firing the weapon implies that she has run out of options with someone who is presenting a clear threat to her life.

So, the recoil reduction is an issue for training, even if we work her up from minishells with birdshot, to regular shells with birdshot, and so on. The issue of recoil is only a concern for training, once she gets the hang of the whole "push-pull", the bridshead might go back on the thing, it would be up to her. After she shoots a few hundred shells, she will have her own opinions.
 
I have a heat shield on a Shockwave, and it does not block the beam of a CT-LS250. It is the very common cheap polymer type sold for Mossbery 500/590, and while one needs to elongate the holes in the outward direction a few mm in the bottom "clamp" to accommodate the thick barrel of the shockwave, and allow the screws to thread (1/2" screws are needed here, as the short ones that come with the heat shield will be too short) it otherwise works and looks fine.

Now, I went overboard (of course) and installed a #5-40 set screw sticking up out of the in the threaded hole where the muzzle bead was, and partly drilled into the underside of the heat shield so that it would fit over the protruding set screw, so that the heat shield would have something more than just friction to keep it from twisting/rotating around the barrel. I also drilled and tapped the heat shield itself for the same bead removed from the barrel, moving the bead slightly further towards the muzzle to avoid the aforementioned set-screw. Blue Loctite on both the setscrew and the bead threads, of course - you don't want that setscrew protruding down into the barrel.

So, go for it - worked for me!
Thanks. I was going to just get the $50 kit from Shockwave with the heat shield, fore end and the tool to pull everything apart. Guess I’ll put it back on the list. Gonna have a new toy in a week, to play with first. The wife is handing over her un fired S&W shield 9 that I got her last year. Lol Her medical issues made the slide too hard to rack, even with the cheater, so she’s going back to her Derringer..yay me. as far as shorty shells, I’ve got a few hundred Aguila’s in buck and slug by just watching Ammoseek periodically. Mix and match 8 in the tube and your wife will be a happy camper. ( with the Opsol, of course)
 
Last edited:
Thanks. I was going to just get the $50 kit from Shockwave with the heat shield, fore end and the tool to pull everything apart.]

That may not be the same part - what I got was verified as being non-interfering by the shopkeeper at http://www.shotgunheatshield.com
But it may be the same actual heat shield. Polycarbonate, slides over the barrel with a friction-fit 7/8ths band at the receiver end, and comes with two half-circle clamp-bands for the muzzle end, which screw on from below, with (gack) Phillips-head screws provided that are too short, and crafted from the most inexpensive pure Chineseium. (The correct screws would be #4-40 1/2 inch button-head screws, like this https://www.ebay.com/itm/174918450156 ) You only use the endmost band, as the inner one would get in the way of the magazine cap. You also need a wood clamp to compress both the heat shield and the clamp-band to get them to fit around the thicker Shockwave barrel.

So many little fiddly details over a stupid hunk o' plastic, but it ends up staying put, making burns almost impossible, and looking competent. Loctite two #4-40 1/4 inch button-head screws (same vendor as above) into the unused brass inserts provided for the clamp-band you could not install, and the brass inserts won't show. It is amazing how much garbage is sold as "gun accessories".
 
Thanks. I was going to just get... fore end and the tool to pull everything apart.

You don't need a forend wrench. The flat metal wrench one uses to tighten the nut on a table saw blade works PERFECTLY, as would any flat and sturdy hunk of scrap steel. But you must first remove the forend from the receiver, which is something one should to learn how to do, and more importantly, how to reassemble correctly. The only problem is holding the cartridge stop and interrupter against the inner surface of the receiver so that the trigger group slides in nicely, and that is just a knack that takes a half-hour of frustrating practice to teach yourself how. You have to clean it, and cleaning means disassembly, and there are lots of videos to show the steps. The ONLY hard part with a Mossberg is the aforementioned stop and interrupter. (I'd leave the trigger group together if I were you, as there is no need to disassemble it for cleaning, and there are too many parts for most people to manage.)
 
This is, without a doubt, one of the most interesting threads we have ever had.
 
You don't need a forend wrench. The flat metal wrench one uses to tighten the nut on a table saw blade works PERFECTLY, as would any flat and sturdy hunk of scrap steel. But you must first remove the forend from the receiver, which is something one should to learn how to do, and more importantly, how to reassemble correctly. The only problem is holding the cartridge stop and interrupter against the inner surface of the receiver so that the trigger group slides in nicely, and that is just a knack that takes a half-hour of frustrating practice to teach yourself how. You have to clean it, and cleaning means disassembly, and there are lots of videos to show the steps. The ONLY hard part with a Mossberg is the aforementioned stop and interrupter. (I'd leave the trigger group together if I were you, as there is no need to disassemble it for cleaning, and there are too many parts for most people to manage.)
Ahh, I see we are on different pages. You have mounted your shield to the barrel. I want mine mounted to the fore end so they move together, allowing me to grab the whole mess and hold the barrel down when firing. My quick mock up is a chunk of squashed exhaust pipe which lets the laser shine through the inside, maintaining my design goal of being ambidextrous. 7C6F6F72-A8CF-4948-860B-156ADA1C1C58.jpeg
 
Last edited:
Back
Top