Modified vs Cylinder bore

C

copeland

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Ok so I am interested in one of the 590a1's that have recently been brought in.

My curiosity is the difference in barrels all I can tell is that modified bore is choked about 10% more vs cylinder bore.

This does not affect 00 buck or slugs, though it will tighten up patterning to a certain distance. For a bush protection gun or short distance shooting at the range does this really matter? I think I've only ever shot cylinder bore, including my 20" 590a1.

The modified bore seem to sell faster, but does it really matter?
 
if you intend it for mostly slug shooting, go cylinder. But if you expect to be shooting any amount of shotshells, go with the modified.
Personally i would prefer an improved cylinder choke in a defense shotgun.
 
At 15ft, my CB (Cylinder Bore) 18.5" Road Blocker was punching 3 to 4" holes while my 14" CB had about a 5 to 6" spread (talking about the Entrance, no clue on the Exit). My point is, that the choke isn't the only factor - the length of the barrel is also a big factor. It wasn't that scientific, but I was having fun at the farm... posted this elsewhere. That Laminate table was about 1.5" thick. Whether this experience actually tells you much, I really don't know. All I know, that it was FUN and I wouldn't want to get hit even with the tiny 2 3/4 - 7.5's.

Had a little fun today with an old dining table on the farm... leaned it up to an earthen backstop and shot 10rds of 7.5 and 10 rds of 00 Buck from 15ft. Shot my Roadblocker from the hip so unsure if you'll be able to see the spread or any type of pattern. It was getting so dark I needed a flashlight to find my spent shells...

Entrance:

cc149877-a589-48e1-b24c-55f35d562919_zps27eb657a.png


Exit:

tableshotgun1_zps1c7470f0.png


Shotty's

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Majority opinion is that slugs will shoot well out of modified barrel as well.
Perhaps even better and more accurate than out of cylinder.

I personally am not sure about that and would like others to chime in on this subject as well.


Cheers,
Dan
 
So it really comes down to a modified choke compensating for the shorter barrel?

Ie. A 14" mod barrel should pattern similar to a 20" cyl barrel?
 
copeland said:
So it really comes down to a modified choke compensating for the shorter barrel?

Ie. A 14" mod barrel should pattern similar to a 20" cyl barrel?
Click to expand...

Unsure if what I experienced says that, but that the barrel length is definitely a factor. Someone with a 14" MOD and 14" CB should do some experiments... The longer barrel may have the shot coming out at a higher FPS as well and may effect the spread. Unsure about a smooth bore, but that's usually the case in a rifle to a certain point.
 
Well the pictures are pretty entertaining.

The only other option is guess would be a mod choke breacher to screw in. I'm a hair from pulling the trigger on cyl bore. Just want to make sure the mod choke won't give me regrets.
 
copeland said:
Well the pictures are pretty entertaining.

The only other option is guess would be a mod choke breacher to screw in. I'm a hair from pulling the trigger on cyl bore. Just want to make sure the mod choke won't give me regrets.
Click to expand...

There'd be a difference but whether it's significant enough to make a difference for what you plan on using the SG for is up to you to decide. If it's simply for sh!ts and giggles recreational purposes, stop fretting and buy it. You missed a fantastic deal already at SFRC.
 
Well guys its like this, fire 50 slugs through a modified choke, and I doubt that it will give you modified shot patterns anymore. A modified choke produces pretty nice buckshot patterns compared to an open choke though. I'm intending to get my 590 barrel threaded for choke tubes so I can have both modified and cylinder bore, and a choke that extends past the muzzle should protect it from dings on the rocks around here.
 
Regardless of barrel length, a chokes affect remain the same.
Slugs will preform well with all, increasing in accuracy the tighter the restriction. Modified being the peak reccomendation.
They will not wear out a choke. Its soft lead, being channeled through hard steel.
If you have the opportunity to buy a tactical shotgun with a modified bore, then I suggest you do. You will have more than ample time to buy open cylinder shotguns everywhere else.



 
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Also remember that the shotgun in question does not employ a choke "tube". The barrel has been bored and tapered by the manufacturer to the specifications and dimensions of a modified choke.
 
In a defensive type shotgun, a tighter choke makes for much more useful practice with birdshot IMO.
 
Boomer said:
Shotgun barrel steel cuts like aluminum, it'll wear, some choke tubes might be tougher than others though.
Click to expand...


It's Mossberg 590A1 compact, one of the toughest shotguns on the market, with extra heavy and thick barrel.
As mentioned there are no choke tubes, barrel is manufactured to specs of modified choke.
 
lanis said:
It's Mossberg 590A1 compact, one of the toughest shotguns on the market, with extra heavy and thick barrel.
As mentioned there are no choke tubes, barrel is manufactured to specs of modified choke.
Click to expand...

Most shotgun barrels seem to be of soft steel though, which might be one of the reasons they use so damn much of it on certain tactical models.
 
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