Mossberg 51M

[dh1633pm]

Just got a Mossberg 51M. Has the original sights. Boy was it dirty. Cleaned almost everything in my ultrasonic with some degreasers. I will post some pics after reassembly. I like that era Mossberg. Question that I can find answered is differences between an A and B model?

second best ways for cleaning inside the receiver?

 

[nhcruffler]

I don't think I've ever seen one of those. Not much info, On the web, on cleaning either. I d suppose once you remove the end cap you should be able to remove the bolt. From there I would be trying pb blaster and a toothbrush. Might have better luck on rimfirecentral.com. Either way you got a neat old .22

 

[Scooter22]

Go here for the most info on the web on old Mossbergs.https://www.rimfirecentral.com/forums/forumdisplay.php?f=51
There were 2 versions of the 51M. A "flat back" and later "cone back" referring to the receiver plug. They were different internally. Then the 51M evolved to the 151M series. Only use standard velocity ammo in any 51M series. I have a bunch of old Mossbergs. They are great rifles. Good luck.

 

[dh1633pm]

Scooter thanks for the info. I am in Central NY too just East of Syracuse. I had read about using standard ammo only. I will follow the link too. Those old Mossberg were very interesting.

I do have is disassembled fully. I took pictures so ensure reassembly. It was pretty dirty inside.

 

[indy1919a4]

Another wonderful website on Mossbergs, its a nice guide to help keep the dizzying number of mossberg models straight.

http://gun-data.com/Mossberg_models_years.html

 

[Merle1]

try here for additional info and parts

https://www.havlinsales.com/

 

[Scooter22]

Heres a link to the 51M specific info. Just scroll down. Many times with Mossbergs the a,b,c after the model number was just a change of sights over the years.
https://www.rimfirecentral.com/forums/showpost.php?p=6069449

 

[indy1919a4]

Those darn Mossbergs are so well built and quality that you can pick up excellent condition used examples today. They will be in the 200 dollar range and better then some of the 22s make today. I can never understand getting someone one of those crickets when there are older Mossbergs that will out live the receiver.

 

[dh1633pm]

Almost back together. Used PB Blaster to clean out the action. Didn’t notice a couple other problems. Bore is shines like new crime. Appears to be lead filled. The screws that hold the cap or whatever you call it are all striped, but the cap isn’t. I could find the parts anywhere so I got two stainless screws at true value. Same tread pattern as the screws you used for an outlet cover. Lastly there is a break in the rear receiver where the rear sight attaches.



You can see the stainless screw in the pic as well.

The action is now much smoother. Waiting for the inner mag tube from gun parts. They are very behind on orders.

 

[indy1919a4]

....Appears to be lead filled....

Tough luck on that break.. But what did you mean "Lead Filled"

 

[dh1633pm]

Bore looks like streaked lead. Reminds me of after a lead solder when you wipe the lead with a wet cloth.

 

[indy1919a4]

Ok, that I understand.. The way I read it it sounded like you were saying it was a good thing... And I was just confirming... Looks like you can get it out..??? Had one like that and some bore cleaner did it..

 

[22250Rem]

Years ago a friend got an old single shot 22 at a yard sale, ( forgot the make), that had a thoroughly leaded bore. Spent lots of time with a brush & Hoppes #9 but it eventually looked mint. He'd let it soak for hours before brushing again but after many repetitions of this it eventually cleaned up and shot great.

 

[indy1919a4]

Years ago a friend got an old single shot 22 at a yard sale, ( forgot the make), that had a thoroughly leaded bore. Spent lots of time with a brush & Hoppes #9 but it eventually looked mint. He'd let it soak for hours before brushing again but after many repetitions of this it eventually cleaned up and shot great.

Everyone know lead preserves the rifling

 

[dh1633pm]

It does. Have it soaking with wipe out. It will come out. I have this thing for old Mossberg 22’s. I am looking to get more than the two I have now. The other is a Model 46BT.

 

[dh1633pm]

A little lead to smooth things out might not hurt too much. Lead city has to go. I am not a bore scrubber on my rim fires til they shoot poorly.

 

[dh1633pm]

Got it all cleaned out. Parts arrived from Gun Parts. Slow processing. I checked it for function by loading the mag. It cycled just fine. I removed a bullet and dumped the powder on a round of .22. Shot it in the basement. It went bang. A muffled bang, but it was a bang. Have the rear site bit the second screw hole is goofed up. Might have to fix that. Otherwise this is what it looks like all cleaned up.

 

[indy1919a4]

Got it all cleaned out. Parts arrived from Gun Parts. Slow processing. I checked it for function by loading the mag. It cycled just fine. I removed a bullet and dumped the powder on a round of .22. Shot it in the basement. It went bang. A muffled bang, but it was a bang. Have the rear site bit the second screw hole is goofed up. Might have to fix that. Otherwise this is what it looks like all cleaned up.

View attachment 937255 View attachment 937256

That is a darn pretty stock

 

[NIGHTLORD40K]

Got it all cleaned out. Parts arrived from Gun Parts. Slow processing. I checked it for function by loading the mag. It cycled just fine. I removed a bullet and dumped the powder on a round of .22. Shot it in the basement. It went bang. A muffled bang, but it was a bang. Have the rear site bit the second screw hole is goofed up. Might have to fix that. Otherwise this is what it looks like all cleaned up.

View attachment 937255 View attachment 937256

Good score!

My Dad has several 51 and 151s, shot the snot outta them as a kid. Im sure we shot lots of HV ......

Originally there would have been a shroud around the front sight posts, which really improves the picture. IMO worth seeking out if your so inclined.

 

[dh1633pm]

I will look for the shroud. I also need to repair the rear screw hole for the target sight.

 

[dh1633pm]

Shot this today. It did terrible. Failure to cycle, jams, double shots. I cleaned it really good. Assembled it carefully and correctly. Will break it down again to see if I can figure it out. On the good side my Other two Mossberg’s shot great!

 

[indy1919a4]

Shot this today. It did terrible. Failure to cycle, jams, double shots. I cleaned it really good. Assembled it carefully and correctly. Will break it down again to see if I can figure it out. On the good side my Other two Mossberg’s shot great!

Hey before you do to much work, you may try a different brand of ammo.. I have fixed a few issues with different ammo. What is a double shot???

 

[dh1633pm]

Yeah it shot twice once. I liked that part. Figured I would take one of my others apart and take a look see. Since the seem to have the same action. Could be the ammo, but the other two did great on it with similar actions.

 

[NIGHTLORD40K]

Shot this today. It did terrible. Failure to cycle, jams, double shots. I cleaned it really good. Assembled it carefully and correctly. Will break it down again to see if I can figure it out. On the good side my Other two Mossberg’s shot great!

Ya, thats the same action as my daughters vintage Plinkster. They are kinda unique in that they "fling" new rounds out of the tube magazine as the bolt is retracting rather than push/strip them as the bolt is going forwards. Watch closely as you pull the bolt back and you will see it shoot a round out of the mag into the chamber.

Hers is quite picky with regards to bullet profile. It will not feed truncated cone bullets reliability. It actually likes el-cheapo Remington Thunderbolts the best!

It also requires a good cleaning every 500 rounds, and even so jams are not unheard of. That tiny ejection port and the tube magazine dont make clearing them easy, either.

Speaking of the tube, IIRC, some of them had a feed angle adjustment. If the angle of the tube isnt right, then the ammo wont hit the chamber mouth squarely wich can lead to problems.

All of that said, though, hers is very accurate, so I put up with its issues, lol.

Slam-firing on that gun is probably the result of a binding firing pin, Im thinking........

 

[dh1633pm]

Going on a motorcycle ride this morning but before I go I am going to put wipe out in the bores of all three for a good cleaning. I will tear the 51M down to parts again. I will look at it’s tube mag for any issues. Put things back together tomorrow.