Mulling idea of 870 build (but have limited 870 knowledge)

[Butcherbill]

Thanks for sharing information. I will likely go with an 18 inch barrel. I think I read somewhere before about the dimples.... yeah, I don't think I'd want to drill them out either. Swage or expand from the inside would be the preferred option. I know that my 1 round S&J extension for my Benelli was OK with the factory spring, I wonder if a 870 with a +2 extension would be OK to use a factory spring ?

My Rem factory +2 came with a longer mag spring, I can give you the length measurement if you need it. I swapped it for a S&J mag tube spring, they come long so you can trim to length for any gun. The +2 definitely has a longer mag spring than the one the standard mag tube comes with.

 

[Munkey1973]

My Rem factory +2 came with a longer mag spring, I can give you the length measurement if you need it. I swapped it for a S&J mag tube spring, they come long so you can trim to length for any gun. The +2 definitely has a longer mag spring than the one the standard mag tube comes with.

Thanks Butcherbill, if I go this route then I will likely do the same !

 

[manbearpig]

If I were to buy something like a 870 Express (1st photo) with a 4 round mag, could I use a mag extender (like one's sold by the good folks at S&J) to achieve that flush look ?

If its doable, are there any pitfalls to such a build.... or should I just keep watching the market to see what comes available for Marine/Police ?

The only real pitfall is that if you'd like your mag extension and barrel perfectly flush then you'll need to make sure you're ordering the right extension for your barrel. They're all different and for example an S&J +2 extension may be half inch longer than a choate +2 extension.
I'm pretty nitpicky about this as well (I think they look best when flush) so I ended up having to buy several extensions before I settled on one.

Also there is a massive difference between an 870 Police and the typical 870 Express. My 2005-ish Police cycles like butter. I have a recent production Express that I've spent hours polishing and hundreds of shells trying to smooth up and it's not even close.

 

[Munkey1973]

The only real pitfall is that if you'd like your mag extension and barrel perfectly flush then you'll need to make sure you're ordering the right extension for your barrel. They're all different and for example an S&J +2 extension may be half inch longer than a choate +2 extension.
I'm pretty nitpicky about this as well (I think they look best when flush) so I ended up having to buy several extensions before I settled on one.

Also there is a massive difference between an 870 Police and the typical 870 Express. My 2005-ish Police cycles like butter. I have a recent production Express that I've spent hours polishing and hundreds of shells trying to smooth up and it's not even close.

Yeah, I'm kind of getting general impressions that Express have some quality issues. I browsed over a post couple years ago that the quality control went right to sh#t with all 870 a few years back when Remington ran into financial difficulties.

 

[unstableryan]

figure I might have been able to do +7, but only found a +6. 870 super mag. Holds 11, or about 16 of the little shells. Can't remember. Clamp went missing at some point but it doesn't seem to notice.

 

[Butcherbill]

Yeah, I'm kind of getting general impressions that Express have some quality issues. I browsed over a post couple years ago that the quality control went right to sh#t with all 870 a few years back when Remington ran into financial difficulties.

I haven’t found that to be the case on the later years, they’re pretty well made. I’ve done some polishing of the action bars but that was by choice, not need. Chambers were all mirrors, no rusting issues but I make sure it dries fully if I’m out in the rain with it and it gets wiped with an oily rag after. The bare minimum that a blued gun needs, I think if it’s a Wingmaster most people take better care of it. They automatically think an express isn’t worth as much so less attention is given to them, unlike the holy Wingmaster lol.

 

[Butcherbill]

OP, here’s some good straightforward videos that run through most things 870.

https://youtube.com/playlist?list=PLzPVXnz7gkEXSPRg6bGdbquEwfJFupUYL&si=bJvY2NBLmOWd9jfT

And two from the above gallery that talks about extensions and springs as well as mag tube caps and spring retainers.

 

[Munkey1973]

View attachment 916874figure I might have been able to do +7, but only found a +6. 870 super mag. Holds 11, or about 16 of the little shells. Can't remember. Clamp went missing at some point but it doesn't seem to notice.

Ga-damn ! Thats a hella lota shells !!

 

[manbearpig]

Oh - I almost forgot to mention:
If you're as nitpicky as I am about the mag tube extension and barrel being perfectly flush, wait till you find out that all mag tube clamps don't hold all mag tube extensions perfectly parrallel

 

[99Solutions]

99Solutions, what nut are you talking about? The S&J extensions are a one piece construction .... there is no separate nut .....

The mag extensions for 870s have either 1 or 2 pieces.

I’m not talking about the tube portion.

I’m talking about the threaded portion that serves as a coupler between the tube on the action and the extension tube.

I’ve used a few. On some of them the nut itself can be finicky. If screwed in too far it can actually reduce one shell capacity, while screwing it out too far on some can cause the mag spring to catch on the edge and hang up.

It depends on the specific extension tube, but I suspect the one on this model may be longer. I haven’t handled one exactly like this model myself so I’m not speaking to this specific one. Just my educated guess.

 

[manbearpig]

It's been awhile - I had one years ago but ended up selling it, so I have no idea what recent production is like:
What he's referring to is that the S&J mag extension is machined from a solid piece of metal, there is no rotating nut. The extension is the nut.

 

[manbearpig]

Another option to consider:


Just get a barrel that is flush with the stock mag tube

 

[Ungrateful]

I have a +2 single piece extension on one of mine and really prefer it over the oem style 2 piece extension that needs the clamp. A single piece extension looks a bit weird without a clamp but it makes removing the barrel a lot easier. I have had the rim of a shell get hung up on the lip between the magazine and extension before but it’s rare and only ever happened while loading, not shooting. For some reason. I think I could solve the issue with a dremel if I were really concerned about it.

 

[Painkillers]

Another option to consider:
View attachment 916988

Just get a barrel that is flush with the stock mag tube

 

[Leg]

A +1 mag extension is flush with a 14” barrel, the +2 flush with the 18-18.5” barrel and the +3 extension is flush with a 20” barrel.

The only part of this that holds true is the 14”. How can a +2 be flush with an 18” and 18.5” barrel?

The fact is that it is very much dependant on what brand extension is being used along with whether it’s a factory 18” or 18.5” (2008+) barrel.

The Remington +2 has always extended past the 18” barrel a half inch from when they started making them in the 50s. Most aftermarket +2 extensions were made to be flush with an 18” barrel and were shorter than the Remington factory extensions.

Then Remington cocked it all up in 2008 by making their barrels 18.5” so it was flush with the factory extension. The barrels continue to be referred to as 18” in length by Remington (not confusing at all). From that point on most aftermarket extensions were now a half inch shorter than the new factory barrel.

It’s kind of ironic to me that the OP likes the look of the Marine Magnum with the factory extension flush with the end of the barrel, but they’ve only been made that way since 2008, and some long time Remington 870 fans would consider the factory extension sticking out past the muzzle to be more correct. Some retailers website photos to this day still show the shorter 18” barrel with the extension sticking out past the barrel. Even the Remington website did this for years after the change.



For the OP, as you’re looking to refinish this yourself I’d be inclined to purchase the extension that you like and cut the barrel down to be flush with it before plating.

 

[manbearpig]

It’s kind of ironic to me that the OP likes the look of the Marine Magnum with the factory extension flush with the end of the barrel, but they’ve only been made that way since 2008, and some long time Remington 870 fans would consider the factory extension sticking out past the muzzle to be more correct.

It has nothing to do with being "period correct", it's simply personal preference.
Mag extension sticking past the barrel is visually unappealing to me. I prefer them either perfectly flush, or the mag extension at most a half inch shorter than the barrel.

Mag extension not being perfectly parrallel to the bore drives me absolutely crazy, yet several mag extension and clamp combos end up this way.

This is how I prefer my mag extensions to look:

IIRC this is a Choate extension. Not my first choice at all - I'd have much preferred to keep the S&J - but this combo ended up looking the best (to my eyes).

 

[Leg]

It has nothing to do with being "period correct", it's simply personal preference.
Mag extension sticking past the barrel is visually unappealing to me. I prefer them either perfectly flush, or the mag extension at most a half inch shorter than the barrel.

Mag extension not being perfectly parrallel to the bore drives me absolutely crazy, yet several mag extension and clamp combos end up this way.

This is how I prefer my mag extensions to look:
View attachment 917073
IIRC this is a Choate extension. Not my first choice at all - I'd have much preferred to keep the S&J - but this combo ended up looking the best (to my eyes).

Yes, certainly personal preference. My comment was more because he liked the particular look of a Marine Magnum, but it looked different than that throughout most of its production life.
I also prefer my extensions to be flush with the muzzle unless it has Remington extension, then I prefer the older look extending past. I‘m not a fan of extensions that are half inch shorter than the barrel, as most are these days.

 

[Butcherbill]

The only part of this that holds true is the 14”. How can a +2 be flush with an 18” and 18.5” barrel?

The fact is that it is very much dependant on what brand extension is being used along with whether it’s a factory 18” or 18.5” barrel (2008+).

The Remington +2 has always extended past the 18” barrel a half inch from when they started making them in the 50s. Most aftermarket +2 extensions were made to be flush with an 18” barrel and were shorter than the Remington factory extensions.

Then Remington cocked it all up in 2008 by making their barrels 18.5” so it was flush with the factory extension. The barrels continue to be referred to as 18” in length by Remington (not confusing at all). From that point on most aftermarket extensions were now a half inch shorter than the new factory barrel.

It’s kind of ironic to me that the OP likes the look of the Marine Magnum with the factory extension flush with the end of the barrel, but they’ve only been made that way since 2008, and some long time Remington 870 fans would consider the factory extension sticking out past the muzzle to be more correct. Some retailers website photos to this day still show the shorter 18” barrel with the extension sticking out past the barrel. Even the Remington website did this for years after the change.

View attachment 917060

For the OP, as you’re looking to refinish this yourself I’d be inclined to purchase the extension that you like and cut the barrel down to be flush with it before plating.

Thanks for the explanation, as I’ve seen both variations so many many times. As well as the 18” & 18.5” lengths, hard to keep track of what was made over the lifespan of the 870 lol.

 

[Leg]

Thanks for the explanation, as I’ve seen both variations so many many times. As well as the 18” & 18.5” lengths, hard to keep track of what was made over the lifespan of the 870 lol.

No problem. It is confusing depending on year and factory vs aftermarket. Below is a picture of an older Scattergun Tech 870 with 18” barrel. It’s flush with the barrel.




Vs a newer 18.5” barrel.

 

[old303]

The Remington bankruptcy a few years back put a serious damper on the supply of new guns and spare parts, barrels, etc, and had downstream effect with customizers like Dlask and Tacord not being able to get guns to gunsmith and third-party accessory makers seeing sales drop to a smaller number of people with an 870 to customize. I'd really like to see all that come back, and Remington does seem to be making some new guns again, but I'm not seeing anything like a full recovery yet.