Shotgun Ammunition Information

This article originally appeared on The Firearm Blog.

In this article, we’ll take a look at some curious and relatively lesser-known facts as well as some handy tips concerning the shotgun ammunition. There is no actual criteria as such. I just gathered some thoughts, random facts and other interesting information that I hope will be useful for you and let you learn something new. So let’s see what we have:


You’ve probably noticed on a shotshell box a marking saying “Dram” or “Dram Equivalent”. It is usually right between the hull length and shot weight markings.

It comes from the days when shotshells were loaded with black powder. So “dram” is a weight measuring unit, which was used to measure the black powder weight. Dram is equal to 1/16 of an ounce or about 27.3 grains. Obviously, shotgun shells loaded with black powder are virtually obsolete today. Modern smokeless powders are much powerful at a given weight. If you weigh as much smokeless powder as black powder and load it into the shell, you’ll end up blowing up your gun or severely damaging it. Let alone how dangerous it can be for the shooter.

So, why then they put that marking on the boxes? That’s where the word “Equivalent” comes in. The number of dram equivalent on modern shotshell boxes indicates the amount of power level that particular ammunition is loaded to compared to black powder weight. In other words, by printing the dram equivalent value on the ammo boxes, manufacturers try to say that the shotshell is loaded with smokeless powder, which will generate as much power/pressure as the printed amount of black powder would do.

It is somewhat weird, isn’t it? Why don’t they just put the type and weight of the smokeless powder that is loaded in any particular shell? It is hard to tell. This system was definitely useful when smokeless powder was newly introduced and not all shells were loaded with it. In that period of time, both smokeless and black powder loads were available. So it was useful to have some sort of a comparison reference to have an idea concerning what to expect from the ammunition loaded with the “new” smokeless of powder. Today it seems to be a rather non-practical tradition or maybe it is a requirement for some legislations or sporting federation rules.

Here is a video by Federal Premium Ammunition explaining the meaning of “dram”:


As you know the shotgun gauge number indicates the amount of equal diameter balls that can be cast from one pound of pure lead. However, in the case of .410 bore shell, the “.410” is the actual bore diameter. So it is more like caliber designation of rifled firearms. In order to calculate the gauge knowing the bore diameter and vice versa, there are a couple of formulas, which look like so:

In the above formulas, dn is the bore diameter and n is the gauge.

So from the second formula, placing .410 instead of dn we get 67.57. It means that if .410 bore had a gauge designation, it would be 67 or 68 gauge.

Now, this is just a curious fact and it has no use. If you don’t like this kind of stuff, then skip the next point – it is even more impractical, yet interesting.


Let’s see what bore diameter matches the gauge number. In that case, n will be equal to dn . So using the same formulas we get the approximate number of 46.5. Which means that a .465 caliber (bore diameter) would be equal to 46.5 gauge!


Birdshot has number designations. If you are an experienced shooter you probably already have an idea of what size each birdshot number matches. But for many people, especially for new hunters and shooters, it is hard to remember what sizes have the numbers of birdshot. However, you don’t have to keep in mind that numbers. There is a simple trick to quickly calculate the shot diameter of each birdshot number. All you need is to subtract the birdshot number from “17” and you’ll get the diameter in hundredths of an inch. For example, to calculate the pellet diameter of say #9 birdshot, you need to subtract 9 from 17 (17-9=8) and the answer 8 will mean that #9 pellets have a diameter of .08 inches.


I learned a couple of DIY tricks while watching a Russian hunting YouTube channel, which host was telling about his grandfather’s experience. There were not too many advanced shotgun ammunition offerings in the Soviet Union. Things like special wads that decrease the spread patterns and buffering media were pretty much nonexistent. But the problems and need to solve them still existed, so people had to invent DIY solutions. I talked to a couple of long-time hunters (and researched other sources) and they pretty much confirmed the legitimacy of these tricks (with minor differences).

So, instead of the birdshot buffer (to decrease the pellet deformation), they used potato starch. Sounds interesting, isn’t it? What they did is poured potato starch into the shell right on top of a couple of rows of birdshot. Then they shook the shell to allow the starch to find its way into the column and fill the voids between pellets. Then added a couple of more rows of birdshot and repeated the process until the necessary amount of birdshot was loaded and the starch had no more place to go in. For some unknown reason, they used only starch and nothing else with similar density (no salt, no flour, nothing else).

Next trick helped to decrease the spread pattern of the buckshot load. So what they did is poured melted candle wax into the hull, which filled the voids between the buckshot pellets. You may think that it would form a wax slug, which is exactly what I thought first. However, it turns out that because buckshot pellets are much larger and have greater individual mass, they separate from each other unlike the birdshot, which forms a wax slug. However, they separate with a delay of a fraction of a second which makes the buckshot patterns tighter in normal shotgun hunting distances.

TAOFLEDERMAUS YouTube channel earlier tried to make a wax slug made of buckshot and it worked for him as a slug. So I guess it is all about what type of wax to use or maybe the technique of applying candle wax to make the buckshot pellets separate with a delay.

I have to say that I haven’t tested these methods and I DON’T RECOMMEND you to try them. I am just sharing with our readers the interesting information that I came across. Now I warned you … if you try them and blow your gun, don’t blame me 🙂

If you are an avid hunter then you were probably aware of most of the subjects discussed in the article. Moreover, you may know about more interesting things which could be a good addition to this article. So, if you do know something like that, please share it with us in the comments section.

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