Modified vs Cylinder bore

Any idea why slugs fly so high with short barrels? Is the slug just erupting out the barrel so early with such force that it's essentially volleying its way towards the target?
 
The US military has had a long history of the effective utilization of 12 gauge shotguns.
During the Vietnam War USN SEAL CWO Watson used a pistol gripped extended magazine Ithaca pump gun to initiate night ambushes of the VC along the Mekong Delta.

These days, many US military bases (I will not list them here) use 590/500 shotguns for their base security detachments. Sometimes in full public view, and sometimes just very close by, but hidden from prying eyes. Might seem a tad bit moot when one stares down a tank cannon barrel at traffic choke points! lol
 
^This one answer makes a lot of sense when you compare rifle iron sights, front and rear, to the relatively low mounted single bead sight of a smoothbore shotgun.
Especially so when you think about the our iron cheek weld, so low on the comb we place our sighting eye to dispel felt recoil from numerous shotgun discharges.
Maybe, just maybe this tends to sling that single projectile higher because of a triangulation effect of, low sighting eye, bead, higher POI???

Good thinking farmer47.
 
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Yes, the closer the bead is to the receiver, the higher you sit your sight picture to see it over the reciever. This increases the angle and moves POI up from POA.
 
2bad4u2 said:
I like the way you think. I fell in love at first sight seeing this...

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Damn I like the look of that.
 
EL34/6L6 said:
I wouldnt get too excited. There is often a large discrepancy with POA vs POI with GRs on short barrel shotguns. You'll be sacrificing accuracy for perceived low cost extras that won't add anything extra to function. A simple bead in this configuration is more effective.
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Unless the bead is on a pedestal to bring it up to the height of the receiver, the gun will shoot high with a bead. A ghost ring and post at least allows the gun to be sighted in, there isn't much that can be done with a bead mounted down on the barrel. Attempting to shoot just as you allow the bead to drop out of sight below the receiver, in an effort to put your pellets on target, isn't particularly quick or precise.
 
a heads up for you shooters that might be changing your stock to a pistol grip . i have read on the internet that you can damage the internals of the receiver if you screw the stock bolt in too deep . i am going from memory here and do not know if this is accurate information . maybe someone who is more knowledgeable on moss berg shotguns can chime in here. i would hate to see someone damage their new gun .
 
farmer47 said:
a heads up for you shooters that might be changing your stock to a pistol grip . i have read on the internet that you can damage the internals of the receiver if you screw the stock bolt in too deep . i am going from memory here and do not know if this is accurate information . maybe someone who is more knowledgeable on moss berg shotguns can chime in here. i would hate to see someone damage their new gun .
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Theoretically, I would believe you are correct and that this is true. However, I believe the only way it would be possible to screw the stock bolt in too deep is if you are using a bolt with improper length or a grip/stock that is out of spec. From factory, they are usually torqued on VERY tight in my experience.

Edit: sorry for derailing
 
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Brutus said:
^My few personal experiences too. I have a few Ithaca riot guns. Which seem to perform pretty good with buckshot or slugs with the cylinder choke.

However while small game hunting in the same shotguns, 1 7/8 ounce BB lead was killing by sheer luck of volume of shot, versus density of pattern.

At 30 yards one lonely pellet found the sitting hare, breaking foreleg and entering the chest cavity. I've had very similar results with #3 buckshot out of a Savage Camper 24-C with it's cylinder choke as well a long time ago.

Using the Ithaca riot gun at 35 yards on a ruffed grouse demonstrated a weak ineffectual pattern using old Canuck #4 birdshot.
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That's why all of my subsequent shotguns will have an adjustable choke system of some kind, anything that's not at least Light Modified is going to marginal at any kind of distance with cheap shot.

My IC choke barrel for my 870, which will throw respectable patterns even with cheap buckshot, is laughable with target loads.

Stuff that looks close enough to spit on is almost ignored by these huge patterns. My Mod choked Dlask barrel and Ithaca 37? Not so much.
 
Boomer said:
Unless the bead is on a pedestal to bring it up to the height of the receiver, the gun will shoot high with a bead. A ghost ring and post at least allows the gun to be sighted in, there isn't much that can be done with a bead mounted down on the barrel. Attempting to shoot just as you allow the bead to drop out of sight below the receiver, in an effort to put your pellets on target, isn't particularly quick or precise.
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Yes we were discussing this already in another thread. There I mentioned I had little problems seeing the bead on my 14" yesterday. I may invest in a taller bead, but ill see how my cheek riser works out first.
Slugs shot a bit hight at 30 yrds, so I compensated. At close range targets were easily acquired and on mark. GRs may be able to get sighted in, but for one distance. Then compensation is needed for anything further, just the same.
GRs are nice for slugs, but not needed if you know your gun. I d rather use my open cyl 20" 590 for heavy dedicated slug target shooting anyways. I also wouldn't want GRs for close range, which is what this gun is designed for. If I need to shoot a slug for predator defense with the bead 14" it likely will be closer than further away. Its all preference.
 
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farmer47 said:
a heads up for you shooters that might be changing your stock to a pistol grip . i have read on the internet that you can damage the internals of the receiver if you screw the stock bolt in too deep
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Non-issue if you have a correct stock made for the 500/590/88 and a proper length bolt. I swapped a bunch and had no problems. Usually the only problems you will run into is that you lose the ergonomics of the top mounted safety position with a pistol grip stock or the trigger assembly will not release until the new stock is loosened off (which can be fixed by taking off a little material from the stock).

The short PGO has it's own bolt that comes with it.
 
copeland said:
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?
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Actually it will affect the slugs - with modified you will be limited to soft lead slugs only
 
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