New Mossberg 590, two questions.

J

Jonathan12

New member
Ok, I managed to get myself a brand new in box Mossberg 590 (not A1). Item number is #50665, it's the matte blue finish 590 with the speedfeed stock. I have a couple things I need to ask...

First, I need to know if the forend assembly (meaning the inner tube, the operating rods, everything) on the 590 is the same as the 500. Seems like an odd question, but I do need to know if they are interchangable (I need to order a second pump assembly). And I haven't been able to look at them side by side yet, but they look identical to my untrained eye.

Second, it's a 9 shot model. Which, if I'm not mistaken, means it has an 8 round magazine, as "x shot" generally means x = magazine capacity + 1 (chambered round) in shotgun terms. However, it will only hold 7 of my shells in the magazine. The shells I have are Sellier & Bellot 12 guage 00 Buck, listed as 2 3/4" shells, and they have an actual length of 2 1/2". Is there a reason the magazine will only hold 7 of these?

-Jonathan
 
1) no clue.

2) It may be an 8 shot model. my 500 had a dowl in it i had to remove to go from 3 shots to 6 shots, but i dont know why they would put one in there to hold off the last shot.

Are you positive its a 9 shot model?
 
Positive, item #50665, and in fact all the 20" 590's, are listed as being 9-shot. If I'm not mistaken, the dowel is only on 500's (except the special purpose models)...it would be quite pointless to insert a dowel that only knocked one shot off the count. Or I'd think so, anyway...then again 922r is pointless too but anyone with an "assault weapon" has to live by it.

-Jonathan
 
From havlin sales...
http://havlinsales.com/default.htm
beforeoldstyle.jpg

Comparison of action slide lengths: top 7-5/8”, bottom 6-1/2” Measure from top of threads to bottom of collar that holds the action bars. This measurement is critical to fit when ordering forearms or stock sets that include a forearm. For the most part, 20-year and older sporting shotguns and new tactical shotguns use the 7-5/8” slide. New sporting models have used the 6-1/2” slide for almost 20 years. There are exceptions, however. To be sure, measure!
I do not think the action bars are different but a call to Mr.Havlin will settle uncertainty as he is well versed in the Mossberg pump guns.
Brent
 
I do not own a 590, but I do own several shotguns including a couple of 20-21" Remington's with mag extensions. They are 6 and 7 plus 1 respectively. To get an 8+1 would require a 22" or longer barrel with a flush mag tube.

Each shell is 2.5 inches long unfired. 2.5 inches times 8 is exactly 20 inches. That would leave no room for the compressed magazine spring and follower. The math don't add up for it to be a 9 shot even though it is listed as such.
 
I'll see about contacting Havlin then about the slide. Thanks!

So the math would indicate that it has to be an 8 shot model...Mossberg needs to fix their website then, every 20" 590 is listed as being a 9 shot. Doesn't matter to me, but truth in advertising is always helpful.

-Jonathan
 
It has been awhile since I spoke with Federal, but as I remember 2 3/4 inch shells are measured before the crimping is done, and due to the wadding and the crimp the tactical rounds ened up being 1/8 inch longer then most other 2 3/4's....

I can get eight of the shorter rounds in my magazine and only 7 of the longer...


:)
 
In case some of you are scratching your heads wondering why. A pinch of history may clear things up.

Originally chambers were cut to accommodate brass cases. A full length, 2 3/4-inch brass shell had an uncrimped or lightly crimped wad restraining the shot. Next came paper hulls, they didn't have the strength to be lightly crimped like a metallic casing. So, the a roll-over crimp was used to restrain the over shot wad. Since the overall length was the same, the loaded length was reduced by the amount required for the crimp, around 1/8-inch. Both brass and paper shells were called 2 3/4-inch because they were intended for the same common chamber size.

With the advent of smokeless powders, it was no longer necessary to use the total capacity of the hull. Standard black-powder length hulls now required additional wadding to take up the space provided by smaller charges (in volume) of the new powders in a 2 3/4-inch case. Somewhere along the line, someone had a very bright idea: Use the folded star crimp we know today. The over shot wad can be eliminated as well as some of the filler wad -- quite an economical change. A third loaded length of 2 3/4-inch shells evolved, about 2 1/2-inches long.

Then there was the big change to the one piece plastic wad column, filler wads were no longer used to even up the shell length. By applying a roll crimp of variable length before forming the folded star crimp, variations in powder and shot volumes could be easily accommodated at the crimping station. Deeply crimped shells still start out as 2 3/4-inches cases, but their loaded length will be significantly shorter that their brass forefathers.

Suppose you're the guy who determines how many shells a tube magazine can hold for the purposes of advertisement. Wouldn't you select the shortest 2 3/4-inch loaded shell you could find to define capacity? When the end user can get only 7 rounds in an 8 round tube, it's too late, he already owns the gun. If he complains, tell him he's using the wrong loads. Or, distract him with a discussion on the right and wrong ways to remove the factory duck plug (remembering to call it an environment sensitive limiter just to add to the confusion) so he's left thinking he messed up the mag capacity somehow when he pulled the plug.
 
My issued 590A1 20" holds 8 rounds in the mag tube.

The 2.75" ammo I use is usually Winchester, Remington, or Federal which is in the 2.34" length range. I recall having some S&B 2.75" 00 ammo some years ago and they were indeed longer, which accounts for not being able to get that 8th round in the original poster's mag tube.
 
Ok, now I see. So if the loads are smaller than the 2.5" ones I have now, apparently it will hold the 8 as advertised. That makes sense, as the last round did go in about half way. A small difference in size x8 shells should allow it to easily fit the last round.

Actually the shells I have aren't crimped at all...I would call it "plugged," to be more accurate. They are transparent, and have a plastic cap over the shot instead of the crimp you'd see on paper hulls.

-Jonathan
 
The Mossberg 590 is a 8+1 capacity shotgun with most shells. Some shells are longer than others. With the slightly longer shells you will only be able to get 7+1 capacity.

Standard unfired 2.75" shells measure 2.25". When fired they open up to 2.75" when fired. The crimp is longer.

Sellier & Bellot, Wolf and a few other 2.75" brand shells are roll crimped and are longer, about 2.5" before fired. They still open up to 2.75".

Here is the math:

2.25" x 8 = 18" That leaves just enough room for the spring to compress and hollow metal follower. If a shell is just 1/6" longer it adds up over 8 shells and you will loose a round capacity. Also if you change out the follower for a solid follower like a Wilson or Choate it will cost you a round. You can see the 20" BBL 590 shotguns are tight for tube space.

Try some standard 2.75" shells and you will be able to 8 in the tube.

I would take out the spring retainer and that will give you a little more room in the tube. If you do be careful when you remove the mag cap.


GC
 
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Jonathan12 said:
Actually the shells I have aren't crimped at all...I would call it "plugged," to be more accurate. They are transparent, and have a plastic cap over the shot instead of the crimp you'd see on paper hulls.
Click to expand...
Shell design has come full circle. The stiff transparent plastic restraining an over shoot wad is much the same as the old brass shells. Shells of this type date back to the 1960s when Wanda introduced an all plastic transparent hull. Herters also had transparent plastic hulls. If I recall correctly, some had a metal reinforcement washer in the shell head. Hulls incorporating over shot wads have not generally been popular with reloaders.
 
8+1 of remington 00 buck works in mine. Last one is a bit tricky occasionally but it goes just fine. Weighs one ton fully loaded.:)
 
Well, at least now I know. Truth be told I only keep 6 shells in it...any more and it starts to throw the balance off. But, I was curious as to why the 9 shot only held 7 shells in the magazine...only with shotguns could you get away with that much variation in the loads.

-Jonathan
 
only with shotguns could you get away with that much variation in the loads.
Click to expand...

It's has more to do with the variation in the different types of crimps and probably the length of the wads but I am not a reloader.


GC
 
I have the same weapon and could only fit 7 rounds in the mag tube as the rounds I was using were slightly longer than 2 3/4" and thus, when added up, brought me about 1/2" short of 8 rounds. Doesnt matter to me much as I only keep 5 rounds in the gun at all times anyway (for HD). I just like the longer tube for giving me more options when it comes to capacity vs. having to go with an extended tube assembly.
 
careful

take care with the new gun and full loading. the 590 has (reportedly) had problems with the mag spring binding and you may want to get it 'broken in' (whatever that means) before you try to stuff it full. Also, I think some 590 have dimples on the inside of the mag tube to stop the magazine follower from coming out that could bind up the follower at the end of the tube when loaded past capacity, whether it be due to longer cases or just trying to shove in extra shells.
 
590 mossberg

i just got a new 590, with a knox pistol grip. manual says it will hold 7+1, 3in shell's and 8+1, 2 3/4 shells... so far i've just put 7, 2 3/4 ...sucked em rite up...
 
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