Post subject: Installing A Mossberg Heat Shield On A Mossberg 500?

Purchased a Mossberg Heat Shield Kit for my Mossberg 500. Directions are pretty clear except for the part about what to do with the spacer......directions do not say anything about cutting it but at the lower corner of the directions there is a picture of the spacer showing 'A' & 'B' lengths.....A= 1 & 5/16' (500 6 shot) & 'B' = 1 & 7/8' for 590...etc......am I supposed to cut the spacer to a length of 1 & 5/16'? Just want to make sure before I do anything cutting.......thanks

Post subject: Re: Installing A Mossberg Heat Shield On A Mossberg 500?

the spacer needs to be trimmed so it fits against the front lug on the barrel. This keeps the heat shield from sliding forward under recoil.

Post subject: Re: Installing A Mossberg Heat Shield On A Mossberg 500?

Thank you......makes sense now.........

Post subject: Re: Installing A Mossberg Heat Shield On A Mossberg 500?

Yeah, check your manual, too. I remember there being something about the heat shields and spacer in my Mossberg 500 manual.

Post subject: Re: Installing A Mossberg Heat Shield On A Mossberg 500?

Well, everything was going fine with the installation till I got to the part where you 'squeeze' the rear clamp together a little bit with a vise or a 'C' clamp so the two bolts will fit through the clamp and while doing that the clamp 'popped' off the shield........contacted Mossberg and they are sending me a new one.......looked like of the 6 spot welds only 2 or 3 'took'....the others all had a 'oily' film over them.........so will see how the new one works out.............

Post subject: Mossberg M590A1 heat shield install fact vs myth

Hi, my first post so I know my words prob don't mean spit but I'm writing this for ANYONE who as asked the quetion:
Will the Mossberg heat shield fit my heavy walled barrel 590A1?
The answer is yes, it fits perfectly. I have a model 51660, this is just a bead sight model and the shield slides into place very easily. No scratching, no banging, no nothing. There is no difference at all between installing this on a 590, or a M590A1. The A1 barrel is a smaller inside diameter towards the end of the bore, thus making it thicker. This is why it also, will hold a tighter pattern than the standard 590. That in itself is something to think about.
The main reason I am writing this is because I looked hi and low for a clear answer, but mostly found text book answers that did not sound real life. I hope this will help someone avoid the time wasted looking for this answer.
Edit:
And yes, it looks BAD-ASS on a M590-A1!!! May not be functional, just intimidating. Like a P40 Fighting Tiger? Hmmm? Anyone? yup

Post subject: re: Mossberg M590A1 heat shield install fact vs myth

The 590A1 does have a heavy wall barrel and is larger in diameter than other standard Mossberg barrels. Both start out about the same diameter from the receiver but the standard barrel wall thickness tapers more towards the muzzle. The bore diameter stays the same until it gets to the muzzle where it depends on what choke the shotgun has. The bores of 12-gauge guns can vary anywhere from .720 to .740 inches among various manufacturers. The Mossberg heat shields will fit the 590A1 but it will have to be modified to fit.
Sounds like your 590 has a standard barrel on it and is not a 590A1. It should say 590A1 on the side of the receiver.
The 590A1 comes with cylinder bore choke.
Read this so you understand about bore diameter and choke constriction and why some shotguns pattern different with the same choke. It is good read for all.
Right choke for your shotgun Link:
http://www.wildfowlmag.com/tips_strateg ... un_062304/
GC

Post subject: Re: re: Mossberg M590A1 heat shield install fact vs myth

He said he has a 51660, which is a M590A1 model, so he probably does have a heavy barrel, albeit with a bead sight rather than GR.

Post subject: Re: re: Mossberg M590A1 heat shield install fact vs myth

Yep, you are correct. It is a good 'ol M590A1, and there is no mistaken the thickness of this barrel. It does say so on the left side of the reciever also. The Mossberg heat shield does not have to be modified in any way to fit this barrel. Just put it on last night, not even a hint of a tight squeeze.

Post subject: Re: re: Mossberg M590A1 heat shield install fact vs myth

Thanks for the link, it's always good to review the basics. It did not, however, explain to me how to load the darn thing. J/K

Post subject: Re: Mossberg M590A1 heat shield install fact vs myth

You wrote this above which is not right. That is the reason I suggested you read the link. The bore diameter is the same on the standard 590. The wall thickness is different. They are both cylinder bore. Some shotguns of the same make and model and the same bore diameter and choke constriction will pattern different with the same ammo. It's all in the link.
GC

Post subject: re: Mossberg M590A1 heat shield install fact vs myth

Sorry MAX100, I did not mean to sound disrespectful.

Post subject: re: Mossberg M590A1 heat shield install fact vs myth

Thanks for the info on the heat shield. I am sure many on here will find it useful. Mossberg tells everyone that they won't fit that shotgun.
GC

Post subject: re: Mossberg M590A1 heat shield install fact vs myth

Yes, that had me very hesitant at first. I threw the dice and ordered one anyways expecting to have to do all kinds of crazy things to make it fit. Such was not the case thankfully. Even the provided screews were plenty long enough. I used vise grips insted of a c-clamp also (i cheated).
I just mic'ed my barrel:
.722' id muzzel
.950'OD muzzel
.950'od where front heat shield mounts

Post subject: re: Mossberg M590A1 heat shield install fact vs myth

That is a heavy barrel. The Mossberg standard barrel OD at the muzzle is about 0.860'.
GC

Post subject: re: Mossberg M590A1 heat shield install fact vs myth

Jermflux, et al...
Sorry to bump this old thread, but I need some help.
After reading Jermflux's post, I ordered up the heatshield to go on my 590.
After 3 hours of consternation, bending and stretching metal with a vice, a few scrapes on the barrel... it's half a$$ mounted.
I'm pissed.
It don't fit like Jermflux suggested... at all. The barrel seems like it's too wide.
I have a though. I believe the 590 A1 ONLY comes with the heavy barrel on model 51663 (which is what I have). It's the only model that says 'hvy brl' on the Mossberg site, and this would explain why Jermflux was able to mount the heatshield with easy, and why I'm having such trouble.
That said, any other thoughts on why this thing don't fit...?

Post subject: Re: re: Mossberg M590A1 heat shield install fact vs myth

Sorry, kennedy, but I don't think that is correct. The 51xxx series model numbers are the heavy walled barrel version of the 590 and the the 50xxx series are the regular barrel 590s. Just because the current offering on the website only lists the 51663 that doesn't mean there aren't other 51xxx heavy wall barreled M590A1s out there, which there are. If you read this thread it was confirmend by both the model number and actually measuring the barrel.
That said I am unsure what the problem is with your installation is. I do know there are some heat shields out there that are specifically for the heavy barrel, but I also know others here have successfully installed regular heat shields. Mayby they will read this and post. Try searching as I recall someong posting, M24 I think, very specific step by step instructions.

Post subject: re: Mossberg M590A1 heat shield install fact vs myth

Maybe it's the barrel length that's causing the difference.
For example, the heat shield will fit the 20' barrel, but not the 18' barrel due to where the barrel tapers.

Post subject: re: Mossberg M590A1 heat shield install fact vs myth

http://www.shotgunworld.com/bbs/viewtop ... highlight=

Post subject: Re: re: Mossberg M590A1 heat shield install fact vs myth

It was M24! And from almost a year ago, no less! Maybe I don't have CRS (Can't Remember S**t) Disease after all.

Post subject: re: Mossberg M590A1 heat shield install fact vs myth

I went ahead and bumped it because I've gotten three questions on that this week.