Mossberg 500 locks all the way back

Jackmcgack · July 14, 2015, 10:11 AM

So I bought an older (1974ish) Mossberg 500 for a song, and I think I know why now. When rack it backwards, it often locks up and won't move forward without significant force. I've moved the bolt, bolt slide, and elevator around inside without anything else in place and the peices seem to slide easily enough. The gun also doesn't have a safety, and I'm not sure what that might affect. Any ideas?

Dixie Gunsmithing · July 14, 2015, 10:46 AM

That sounds like a problem with the carrier, or the carrier cam. The cam is spring loaded, and is mashed down by the bolt, when it is brought forward to close the action, in order to raise the carrier. I doubt it is the safety, and I bet it is just the button missing. They made those out of plastic, but you can get metal replacements. I'd try a thorough cleaning of the trigger guard and all the parts in it, especially the carrier.

Jackmcgack · July 16, 2015, 10:13 AM

Cleaned out the trigger group completely, installed all the parts needed... still no go. When you say the carrier cam, I don't know which part you're talking about. Do you mean the action bars?

g.willikers · July 16, 2015, 10:59 AM

Dixie might be using Remington terms and descriptions.
Carrier = elevator = lifter for other makes.
Not sure what the carrier cam is for Mossberg.

Jackmcgack · July 16, 2015, 11:26 AM

Ah, now I see. I went ahead and pulled the trigger group apart this time, and scrubbed the crud off every individual part... tada, it works. Still has a little hang once the bolt is back, but it's not horrible. I'm now up to Mossberg #5 for my collection

Dixie Gunsmithing · July 16, 2015, 11:49 AM

g.willikers, I screwed up, and didn't think when writing the post, that the 500 doesn't use a cam or spring, as it's carrier works like a 31 Remington. I figured it would be dirt causing it, though, and not the safety. Sorry about the mis-post, as I didn't catch that until I read your post.

Mossberg calls the carrier an elevator. I'm used to talking about Remington and Winchester so much, that I automatically use their nomenclature for all guns. Both use carrier.

Generally, that's about the only thing that will foul a bolt like that in a pump, on the rearward stroke; either the carrier broken, a spring, a cam, or just dirt fouling it up. It's dirt in about 90% of the cases. The cam is called a carrier-dog by Remington, but it is really a one-direction cam. Of course the 500 doesn't have it or the spring.

Another old-timers term for the carrier was a flapper-gate.

Dragline45 · July 16, 2015, 12:26 PM

Quote:

Still has a little hang once the bolt is back, but it's not horrible.

When you have the bolt out, look on the bolt and the inside of the receiver for any shiny spots, these will be your high friction areas. I use grease on these areas and it smooths things out tremendously and lasts alot longer than oil.

**4V50 Gary** · July 16, 2015, 07:42 PM

Flapper gate. I like that.

Dixie Gunsmithing · July 16, 2015, 08:25 PM

Gary, that was the term the hillbillies called it, whom were born in the late 1800's, and early 1900's. I think they got the name from the old self closing fence gates, and it stuck. Imagine having a customer call about his model 12 Winchester, and explain that its flapper gate wont work.

I knew one guy, who had an Ithaca semi-auto shotgun, that he pronounced the firearm companies name, along with his brother-in-law, as Itchit. You won't run into this as much anymore, since the WWII veterans are about all gone now. It could be a royal pain to diagnose a gun problem over the phone.

g.willikers · July 17, 2015, 11:09 AM

Years ago, I used to occasionally attend shotgun turkey shoots.
Shoot at targets win a frozen turkey type.
Between times to shoot there were naturally lots of conversations about shotguns.
Some of those old guys might as well have been speaking in tongues, though, with what they called stuff.

natman · July 17, 2015, 06:53 PM

When I was working in a gun shop, I had a customer come in and complain that the chamber wasn't moving smoothly on his shotgun. He opened the bolt to show it wasn't loaded, and said "see, the chamber moves roughly". I pointed out that the rough moving part was in fact the bolt. He said "Gee, I always call it the chamber.".

I informed him he could call it a red, red rose if he liked, but that wouldn't make it one and he would communicate with everyone else in the world much better if he called the part with the handle that moved back and forth the "Bolt" and the hole in the barrel where the shells ended up the "Chamber".

July 14, 2015, 10:11 AM	#1
Jackmcgack Junior Member Join Date: July 14, 2015 Posts: 3	Mossberg 500 locks all the way back So I bought an older (1974ish) Mossberg 500 for a song, and I think I know why now. When rack it backwards, it often locks up and won't move forward without significant force. I've moved the bolt, bolt slide, and elevator around inside without anything else in place and the peices seem to slide easily enough. The gun also doesn't have a safety, and I'm not sure what that might affect. Any ideas?

July 16, 2015, 10:59 AM	#4
g.willikers Senior Member Join Date: September 28, 2008 Posts: 10,442	Dixie might be using Remington terms and descriptions. Carrier = elevator = lifter for other makes. Not sure what the carrier cam is for Mossberg. __________________ Walt Kelly, alias Pogo, sez: “Don't take life so serious, son, it ain't nohow permanent.”

July 16, 2015, 07:42 PM	#8
4V50 Gary Staff Join Date: November 2, 1998 Location: Colorado Posts: 21,838	Flapper gate. I like that. __________________ Vigilantibus et non dormientibus jura subveniunt. *Molon Labe!*

July 17, 2015, 11:09 AM	#10
g.willikers Senior Member Join Date: September 28, 2008 Posts: 10,442	Years ago, I used to occasionally attend shotgun turkey shoots. Shoot at targets win a frozen turkey type. Between times to shoot there were naturally lots of conversations about shotguns. Some of those old guys might as well have been speaking in tongues, though, with what they called stuff. __________________ Walt Kelly, alias Pogo, sez: “Don't take life so serious, son, it ain't nohow permanent.”

July 14, 2015, 10:46 AM	#2
Dixie Gunsmithing Moderator Emeritus Join Date: April 27, 2013 Location: Ohio Posts: 1,923	That sounds like a problem with the carrier, or the carrier cam. The cam is spring loaded, and is mashed down by the bolt, when it is brought forward to close the action, in order to raise the carrier. I doubt it is the safety, and I bet it is just the button missing. They made those out of plastic, but you can get metal replacements. I'd try a thorough cleaning of the trigger guard and all the parts in it, especially the carrier.

July 16, 2015, 10:13 AM	#3
Jackmcgack Junior Member Join Date: July 14, 2015 Posts: 3	Cleaned out the trigger group completely, installed all the parts needed... still no go. When you say the carrier cam, I don't know which part you're talking about. Do you mean the action bars?

July 16, 2015, 11:26 AM	#5
Jackmcgack Junior Member Join Date: July 14, 2015 Posts: 3	Ah, now I see. I went ahead and pulled the trigger group apart this time, and scrubbed the crud off every individual part... tada, it works. Still has a little hang once the bolt is back, but it's not horrible. I'm now up to Mossberg #5 for my collection

July 16, 2015, 11:49 AM	#6
Dixie Gunsmithing Moderator Emeritus Join Date: April 27, 2013 Location: Ohio Posts: 1,923	g.willikers, I screwed up, and didn't think when writing the post, that the 500 doesn't use a cam or spring, as it's carrier works like a 31 Remington. I figured it would be dirt causing it, though, and not the safety. Sorry about the mis-post, as I didn't catch that until I read your post. Mossberg calls the carrier an elevator. I'm used to talking about Remington and Winchester so much, that I automatically use their nomenclature for all guns. Both use carrier. Generally, that's about the only thing that will foul a bolt like that in a pump, on the rearward stroke; either the carrier broken, a spring, a cam, or just dirt fouling it up. It's dirt in about 90% of the cases. The cam is called a carrier-dog by Remington, but it is really a one-direction cam. Of course the 500 doesn't have it or the spring. Another old-timers term for the carrier was a flapper-gate.

July 16, 2015, 08:25 PM	#9
Dixie Gunsmithing Moderator Emeritus Join Date: April 27, 2013 Location: Ohio Posts: 1,923	Gary, that was the term the hillbillies called it, whom were born in the late 1800's, and early 1900's. I think they got the name from the old self closing fence gates, and it stuck. Imagine having a customer call about his model 12 Winchester, and explain that its flapper gate wont work. I knew one guy, who had an Ithaca semi-auto shotgun, that he pronounced the firearm companies name, along with his brother-in-law, as Itchit. You won't run into this as much anymore, since the WWII veterans are about all gone now. It could be a royal pain to diagnose a gun problem over the phone.

July 17, 2015, 06:53 PM	#11
natman Senior Member Join Date: June 24, 2008 Posts: 2,607	When I was working in a gun shop, I had a customer come in and complain that the chamber wasn't moving smoothly on his shotgun. He opened the bolt to show it wasn't loaded, and said "see, the chamber moves roughly". I pointed out that the rough moving part was in fact the bolt. He said "Gee, I always call it the chamber.". I informed him he could call it a red, red rose if he liked, but that wouldn't make it one and he would communicate with everyone else in the world much better if he called the part with the handle that moved back and forth the "Bolt" and the hole in the barrel where the shells ended up the "Chamber".