The Box O’ Truth #45 – Shotgun Chokes and Buckshot Part Two

I have seen a few fellows say, “When using a shotgun for home defense, with buckshot, Modified Choke is best, because it will give the best patterns. Besides, Cylinder Bore spreads too much.”

Is this true? Let’s see.

I measured three of my shotguns today.

One is my Mossberg Maverick that I sawed off to around 19.5 inches.

It therefore has no choke at all, and is a true Cylinder Bore, or Open Bore.

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This type of bore is very common in defensive shotguns.

It should measure .73 inches, and indeed does.

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The next is my Remington 870, which is marked “Cyl”, or Cylinder Bore.

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It should measure .73 also, but it was a little tighter, and measured .724.

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The third is a Remington Special Field, which has interchangeable screw-in chokes.

I put the Modified choke in it.

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It should measure .71 inches, but actually was a little tight and measured .707 inches.

This brings up an important point in this discussion…

Different guns marked with the same choke size, will often have different actual bore sizes.

No really big deal, but just something we ought to know about.

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Well, let’s see if there is very much difference, or “improvement” with the Modified over the Cylinder Choke.

We will shoot the same rounds that we shot in part one, just to be able to compare the data.

I will shoot the three guns on the same target, with the Maverick (Open bore) on top, the 870 (marked Cyl) in the center, and the 1100 (marked Modified) on the bottom.

We will use the same ammo we used in Part One.

Time to get to work.

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We will shoot the groups at 10 yards, which is actually a long distance for most home defense situations.

First, the Wolf 00 Buckshot.

We can disregard the holes made by the wads, but notice the three patterns.

They are very similar in size and shape.

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How about some Remington Managed Recoil 00 Buck.

Again, not much difference in pattern size, but interestingly enough, the tighter choke in the 870 actually had a larger pattern than the Open Choke gun on top.

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Let’s try some Remington 0 Buck.

This load has 16 pellets, but the patterns were not much different in size.

Notice the wad stuck in the paper.

I hated to shoot up that 0 Buck, as it was the last that I had and it is hard to find.

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Lastly, let’s try some Federal Tactical 00 Buck with Flight Control Wad.

As you can see, these loads hold a very tight pattern and make almost one hole at 10 yards.

As you can see, these loads hold a very tight pattern and make almost one hole at 10 yards.

We also noticed that it had some kind of buffering material in the loads that made slight dents on the cardboard.

The Flight Control Wad, combined with the buffer, really makes for some tight patterns.

Here's a blow-up so you can see the dents caused by the buffering material.

Here’s a blow-up so you can see the dents caused by the buffering material.

I cut open a round of the Federal to see what the Flight Control Wad looked like.

Here's the parts as they come out of the shell.

Here’s the parts as they come out of the shell.

Notice that the wad does not have “petals” like other wads, that go all the way to the front of the wad, but is made to stay on the shot longer.

It also has a buffering material in the shell to protect the buckshot, which are hardened and plated to keep them as round as possible

The wad has three small petals that I pried open so that you can see how they work.

These petals just open enough to allow the wad to slow down and back off the buckshot as it is in the air.

This results in the very tight patterns we saw.

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Lessons Learned:
  1. There is almost no difference in the size of the patterns regardless of choke size at home defense distances. Might it make a difference at longer distances? Sure. But I am studying loads for home defense, not deer hunting. And at these distances, there is no real difference.
  2. Some folks said the Modified choke would have “better patterns”. I did not find this to be true.
  3. The main factor in group size seems to be the difference in the brands of ammunition. That means that if we want good patterns, there is no substitute for trying the different loads in your shotgun.
  4. Different shotguns marked with the same choke will often have variances in actual choke diameter. Not a big deal, but chokes are not extremely standardized.
  5. It’s fun to shoot stuff.

(Thanks to Vern for the help)