# Convert 870 express to 870 supermag?



## Longhairedkuntryboy

Can u convert a remington 870 express to a supermag. I have an express I'm wantin to build a turkey gun with. I would really like to be able shoot 3 1/2 shells.  I was thinkin about it and all I would think u need to do is change the barrel. Am I right? Can I just slap a 21" supermag barrel on there an be good to go?


----------



## polaris30144

NOPE....your receiver will not handle 3 1/2" shells....the ejection port is not long enough nor is your receiver designed to handle the power...if it was that easy, no one would ever buy a super mag. I'm not even sure a supermag barrel would mate up to an express action....


----------



## Buck111

Sell the express and put that money toward a supermag.


----------



## Longhairedkuntryboy

Thanks. Thats what i wanted to know.  My dad had a supermag and i was gonna try to see if the barrel would fit and if the receiver would cycle a shell. Was a little skeptical about tryin to shoot it tho


----------



## Twenty five ought six

Suit yourself, but the 3 1/2 inch is greatly overrated for turkey hunting, where lead shot is still legal.  The 3" is ballistically superior to the  3 1/2 in every way except the amount of shot --- which is irrelevant at normal turkey ranges.  

The only reason the 3 1/2" was ever created was for the increased shot capacity with steel shot for waterfowl hunting.

Also, try touching off a few 3 1/2" shells in a pump gun before making a decision.  Been there, done that, sold the gun.


----------



## Big7

They hurt REAL BAD from an H&R single shot short
gun too...


----------



## jo_dawg69

most of the regular plain jane super mags that i have looked at aren't even chambered for 3.5'' shells. only 3''. but then again i haven't looked at the turkey guns either. i know for a fact that the ejection port on them is way too small for the 3.5's. and they seem to be too small for the 3's too.


----------



## ryano

jo_dawg69 said:


> most of the regular plain jane super mags that i have looked at aren't even chambered for 3.5'' .



are you positive it they were super mags?  thought ALL super mags were chambered for 3.5" 

I have a super mag with a 24 inch bbl but really it seems like overkill. My gun actually seems to patterns a lot better with the 3" and its easier on the shoulder. They kick like a mule.

Call me a wuss but i shot a 3.5 through it once. NEVER again.


----------



## ctmoore

*Convert 870 express to 870 supermag*

Look here now!  Recoil is directly proportional to ammunition power or energy.

The 3 1/2 inch magnum is a whole lot more powerful than the little 3 inch shell.  Just fire one of each.  The 3 1/2 has more recoil than a .458 magnum elephant gun round.

If you were hunting T-Rex or Kodiak Bear with a shotgun, the 12 gauge 3/12 inch slug would be the shell you wanted. 

10 gauge, 3 1/2  magnum would be even better but you can't find buckshot or slugs there.  Afterwards, you might need a little physical rehab.


----------



## jo_dawg69

yes I am 100% positive that they were Super Mags.  I looked at about 5 of them at HiCaliber about 3 days ago, and they all said 3''. I thought all supermags were 3.5'' too, but these weren't.


----------



## chase870

jo_dawg69 said:


> yes I am 100% positive that they were Super Mags.  I looked at about 5 of them at HiCaliber about 3 days ago, and they all said 3''. I thought all supermags were 3.5'' too, but these weren't.



All super mags are 3.5 inch guns, you were looking at express magnums, or a supermag reciever with a 3 inch barrel on a super mag reciever. All the 870 parts are interchangeable. You can but a barrell with a 3 inch chamber on a standard 2 3/4 inch reciever and be alright provided you only shoot 2 3/4 inch shells in it


----------



## stevetarget

ctmoore said:


> Look here now! Recoil is directly proportional to ammunition power or energy.
> 
> its really the amount of weight your trying to move down the barrel that causes the extra heavy recoil.
> 
> heres somthing I found on the subject.
> The idea behind the 3 1/ 2 when it was introduced by Federal and Mossberg back in 1989 was to increase case capacity to hold more bulky steel BBBs and Ts for pass shooting geese, and it worked. Because steel is light, the payloads weren’t very heavy, and recoil was tolerable.
> Had 3 1/ 2 inch loadings remained steel-only, all would have been well. Unfortunately, someone looked inside the new hull and said “Hmmmm. I wonder how much lead fits in there?” The answer is up to 2 3/8 ounces. As you increase payload, you increase recoil, and 3 1/ 2 lead loads are awful.


----------



## bfriendly

Twenty five ought six said:


> Suit yourself, but the 3 1/2 inch is greatly overrated for turkey hunting, where lead shot is still legal.  The 3" is ballistically superior to the  3 1/2 in every way except the amount of shot --- which is irrelevant at normal turkey ranges.
> 
> The only reason the 3 1/2" was ever created was for the increased shot capacity with steel shot for waterfowl hunting.
> 
> Also, try touching off a few 3 1/2" shells in a pump gun before making a decision.  Been there, done that, sold the gun.



The 870  12ga is a freakin cannon already..........I just got one not long ago.........after telling my buddy how well I shot some slugs out of it at 50 yards, I asked him......"Why in the world are we shooting these CANNONS"?  Same goes for those 3"high brass turkey loads I am shooting.....WOW!

Of course, when that hog walks out and you put a cannon slug in its shoulder, we remember why we absorb such torcher


----------



## ejs1980

The 3.5 inchers are better for turkey/deer. They have a denser pattern. Granted the shot string is so long it won't be much better for shooting fast moving targets. For stationary targets like deer and turkey the length of the shot string doesn't really matter. To me it's not worth the extra recoil because with the proper load and choke you can have decent patterns all the way out to where penetration becomes a limiting factor. Having the 3.5 shells doesn't increase velocity because they pack in so much extra lead. Like any other magnum they aren't bad when shooting once in the field but those days spent shooting patterns and trying different loads to figure out close you'll have to get the old tom before pulling the trigger you'll wish you had not went with the magnums.


----------



## GAMHUNTER35

yea an i found out with mine that  it will hold 4 2 3/4 shells with the factory plug in it. g/w let me off with a warning the other morning on a dove shoot. so i made me another plug now it will only hold 3 3 1/2 s an 3  2 3/4 shells.


----------



## 10gaugemeow

yeah 12ga 3.5 do have one bad kick to most people i had a stoeger p350 it only weighed 6.4 lbs that thing had 86 ft lbs of recoil with 2 1/4 loads now i shoot a 10 ga . better pattern less recoil


----------



## DeepweR

reckon how the folks back in the ole days got by with only 2 3/4 shells? lol...... i'll never shoot another 3.5in shotgun shell. bout broke my sholder.


----------

