Armory Sponsor
Joined:
May 2023
Posts:
417
EE: 0% (0)
USA
Posted: 5/3/2026 7:30:47 AM EDT
|
found this 500A in a pawn pretty reasonable for a home D shotgun , had the poly furniture but i had a old set that just needed refinishing , as i was fitting the fore arm which required some inletting , i assume the reason was it was off a older gun with a longer barrel and now is on a 18.5 , anyway i noticed the barrel nut that cinches into the mag tube leaves a gap , at first i thought it was hanging up in the receiver but barrel seats in the receiver perfectly should i shim this ? is this common? i found on another forum someone asking the same question but did not get a real/clear answer , i figured i would try here before giving mossberg CS a shot , will probably do so anyway  |
|
Does it do it with the original barrel? Seems like a black fender washer shim would take care of the gap - Nothing to worry about really but hard not to notice if you are bothered by it. The barrel is locked at the breach end by the locking lug in the bolt, holds it together under fire, If its not all lose it should be fine but not attractive. |
|
I think the gap is pretty common. Seems to vary from gun to gun, with some being more of a gap than others. I have read on a couple shotgun forums that it can place a downward flex on the barrel and can effect accuracy. I have a cantilever slug barrel on one of my Mossberg 500's and it had a slight gap. I ended up cutting out some shims out of some aluminum soda cans and stacked a few till it tightened down with no gap. Not sure if it really made much difference. But it I like to feel like it does. |
Joined:
May 2023
Posts:
418
EE: 0% (0)
USA
Joined:
May 2023
Posts:
419
EE: 0% (0)
USA
Joined:
May 2023
Posts:
420
EE: 0% (0)
USA
|
aesthetically it does not bother me , when handling it you really have to hit that sweet spot view to even notice it it so small, i had been working on it for a hour before i even noticed it while fitting the forearm my concern is since the lug and mag tube are not cinched tight that the threads now are absorbing most of the energy of the shotgun , where as if cinched the barrel lug carrys it |
Joined:
May 2023
Posts:
421
EE: 0% (0)
USA
|
no the barrel is not threaded for choke tubes , but i have a 18 1/2 that says Mossberg on the barrel that is not threaded either so that means nothing that i can think of anyway i think i will contact mossberg if they have shims for it thanks for the fast replies , all are /were appreciated |
Joined:
May 2023
Posts:
422
EE: 0% (0)
USA
|
Originally Posted By Migmaqman: well i pulled the barrel , loosened the shield and rotated it and it does NOT say Mossberg , has normal gauge info and address from Eagle Pass Tx ,no company name , so the barrel is aftermarket , this is disappointing , but at least it doesnt say made in china Eagle Pass is the location of the Maverick factory, owned by Mossberg. |
I sell firearms produced by the finest child labor in the world, be it Filipino, Muslim, Mormon, Arizonan, or Texan.
Joined:
May 2023
Posts:
423
EE: 0% (0)
USA
| yea i searched eagle pass TX + mossberg , and it said thats where a lot of their parts come from , didnt say Maverick but that tracks , thanks for conformation , i have a email in with CS so will see what they say , said it can take up to 3 business days for a response , will touch back with what they say |
| You could measure the gap, OP, measure the length of the magazine tube forward of the receiver, heat the mag tube, unscrew it, cool it, put some moar threadlocker on, and then screw it back in to the precise length for no gap. |
I sell firearms produced by the finest child labor in the world, be it Filipino, Muslim, Mormon, Arizonan, or Texan.
Joined:
May 2023
Posts:
424
EE: 0% (0)
USA
|
Originally Posted By Migmaqman: mossberg got back with me , they said it is perfectly normal , and fine , said it even says so in the owners manual which i do not have Think you can download that off their website. |
I sell firearms produced by the finest child labor in the world, be it Filipino, Muslim, Mormon, Arizonan, or Texan.
Joined:
May 2023
Posts:
425
EE: 0% (0)
USA
|
i do not think a O ring would address my original concerns that the take down nut threads are absorbing most of the energy of the shotgun by it not cinching tight , like i said earlier the small space itself does not bother me , if Mossberg addressed this in the owners manual then thats good enough for me that the gap is a non issue , if it was a large gap then i may persist with them over it i will not be loading it with slugs , it is a Home D gun , so if the gap is associated with accuracy issues like someone posted i do not think that will be in play , i have some #4 Buck i will have in it which will be fine for close quarter is ever needed , ive tested on frozen milk jugs of water , a smile was produced one thing that worried me about shimming is the potential of messing with head space , Mossberg's reply put all my concerns to ease ,and im satisfied 100% with my very nice , inexpensively obtained , "you picked the wrong house buddy" shotgun the wood furniture i had was mix matched ,so i sanded it down and refinished , just waiting for a hot day to take it back off and sprat a coat of matte clear over it i had a issue with the fore arm hanging up when it rode up towards the receiver , i think it was off a older ,longer barrel and the taper was more steep on the 18.5 barrel , so i took Vaseline and rubbed it all over the underside of the barrel about 4 inches down from the receiver , reassembled and racked the slide a few times , disassembled and the Vaseline showed me everywhere the fore arm was hanging up , removed material in those spots and badda bing badda boom , nice smoot operation  |
Joined:
May 2023
Posts:
426
EE: 0% (0)
USA
|
i redid my old 870 in 20 ga yesterday that i purchased back i 1993 , that old girl had seen a lot iof use over the years , the finish was all gone in spots and i kept finding rust because of it so in order to stop the rust cycle i stripped the metal parts , still have to do the trigger guard ,its metal coming from that time period , the lumber i did the same time i did this 500A furniture ,its nice seeing the old girl looking good again i have a Uncle Miles 1903 style sling for the 500A , i just put conditioner on it , i will let that absorb in and hit it again , will drill the stock stud and and get that installed , just have to dig one out of the parts drawers |
|
As others stated, very common. I have handled A LOT of 500s and seen this quite a bit. No worries, gun will function just fine. However, the first time I saw it, I was convinced I was sold a defective gun. I even wrote a letter to (yes, it was that going ago) Mossberg about it. Their response was “don’t worry about it”. |
Life is short. If you are waiting for “someday”, it’s here!
Armory Sponsor