Choosing a Blank
Heated words are exchanged … a gun is pulled out of a jacket pocket … a shot rings out! And then the audience can’t hear the next five minutes of dialogue because of the ringing in their ears. How do you know what blank to use when you need an on- or offstage gunshot?
Although it may sound strange coming from a company that makes its money in part by selling blanks, the best sound effect for a gunshot comes not from a gun at all but from your soundboard. Of course, not your old reel-to-reel or cassette player. Taped sound is hard to cue-up and is unforgiving if there is any technical glitch. No, I’m talking about a good modern sound system that accepts an exact cue search from a CD or internal memory. Such a sound can be generated at the sound operator’s touch whenever it is required. With the right equipment a good sound designer can make the gunshot appear to come from any point onstage or off.
If, however, the choice is made to use an actual or live gunshot for the effect, please remember that less is more. Some directors and fight choreographers want very loud gunshots for nearly every show, so please remind such people that audiences need the impression of gunfire, not the real thing. As a matter of fact, most audiences prefer not to be deafened in order to experience verisimilitude. So what caliber should you use?
A brief explanation of caliber: again, it is a number that describes the width of a casing or bullet. In the English or American system it is listed in the hundredths of an inch diameter measurement of the inside of the gun barrel. So .22 caliber is a little less than 1/4 of an inch wide, 38 caliber is a little more than 1/3 of an inch wide, etc. Metric measurement is the same except listed in millimeters.
Caliber describes the diameter of a circle, not the area, so all things being equal a .32 caliber blank is not 50% louder, but over 200% as loud as a 22 caliber blank of the same height. What the caliber also fails to tell you is how long the blank is, so it tells you nothing about the volume of powder inside the cartridge. Ammunition manufactures can make a blank as long as they wish, and filled with as much gunpowder as they wish. For this reason, 32 caliber blanks are actually over six times as loud as the 22 caliber blanks made by the same company.
Some blanks come in volumes reduced from standard, and are called either half-loads or quarter-loads, but there is no industry-wide standard here, so the volume of a “full” load changes with each manufacturer. You would have to know what the standard is for that particular company’s brand of blank at that caliber before you can guess what the half load will sound like. A half tank of gas in a Hummer is going to be a lot more expensive than a half tank of gas in a Vespa. A half load .32 caliber blank from Winchester is about fifteen times as loud as a full load 22 blank from Pobjeda.
Notice that the term used is half-load, not half-loud. Having half of the powder doesn’t mean that the noise produced is going to be half of the full load, for there are other variables that affect the actual sound that the audience will hear. If both full and half loads are packed into the same size cartridge without adding any filler, the extra air in the half-load acts as a kind of shock absorber to the explosion, reducing the sound level considerably. On the flip side, some blanks use primers that make quite a bit of noise themselves, so going from half to quarter load can end up being not very different at all.
For most theatres, .22 caliber blanks are all you are going to need. This is good because they are the least expensive, and can be found at many sporting goods stores. However, there are three commonly found 22 blanks available nationwide and they have very different sound characteristics, even though they are all considered full-load. Your local sporting goods or gun store will usually carry only one brand.
By the way, there exist both rimmed and rimless ammunition in several caliber designations. On rimless ammo the base of the cartridge is the same diameter as the case. Rimmed ammunition has a base wider than the case, which keeps the cartridge from sliding too deeply into the chamber. Semi-automatic ammunition cannot have an exposed rim that would interfere with the loading mechanism, so rimless ammunition was designed for that use.
Why do you need to know this? If you are looking for blank ammunition for your stage gun, you need to know that the two styles cannot be interchanged, even if they are exactly the same caliber. 9mm rimless can’t work for your 9mm revolver.
Some common blanks:
shown in increasing order of loudness: #11 percussion cap, musket cap, 6mm, .22 cal crimped, .22 cal blackpowder, .32 cal blackpowder, 8mm, 9mm half load, 9mm full load, .45-.70 quarter load, 12 gauge, .303 British. The first two are not really blanks, but are shown here for size comparison. Also notice that the full load 9mm is actually a little smaller than its half load equivalent.
Many gun rental suppliers make their own blanks for their own stock, and there are a lot of casual jobbers who hand-load bullets of every caliber for hunters, and can make blanks as well if asked, therefore blanks can be found for every style of gun ever made and virtually any level of sound. But, as you can imagine, hand-loaded blanks are going to cost you. So your first step should be to find out if there are mass-manufactured commercial blanks available. Line up your source early on, for even these will run out on occasion. Blanks that come from foreign manufacturers can experience export delays of several months. American manufacturers, such as Winchester, survive because of military contracts, not the civilian market. So when there is a hot war (for example the prolonged Iraq and Afghanistan actions), all production is focused on fulfilling government contracts. Making blanks for track meets, dog training and theatrical productions is low on their priority list.
Some of the more common varieties include:
• The 6mm Pobjeda and Flobert brands are crimped blanks from a variety of importers, and packaged in a variety of other brand names. They are manufactured in Bosnia Herzegovina and Germany respectively (yes, they will fit in a .22 handgun). At one time they were made by a company called Precise, and they are still commonly referred to by that name. They are only as tall as they are wide, come 100 to a canister, and look like tiny little acorns, which is also their common American nickname. They produce the least amount of sound you can get in a commercial blank because there just isn’t room for much gunpowder. This is about as much sound as you can get away with in 50 to 150 seat houses, especially if the first row is close to the actors. The one drawback is the quality of the sound produced – it has only high register notes so tends to sound “tinny”.
• The CCI brand short .22’s come in boxes of 100, but are about twice as tall as the acorns. Since more powder can be packed inside, they produce a slightly deeper and louder sound. From 100 to 500 seats, this will give a reasonably effective gunshot. The same factory also packages the same blanks under the Remington name.
• Please be very careful here – don’t simply go by the brand name. CCI and Remington also make a full line of .22 caliber blanks made for construction nail guns, but these have much harder cartridge casings that can ruin the inside of a starter pistol or real gun. Found at most hardware stores, avoid these “power loads” at all costs.
• Winchester brand short .22 blanks come fifty to a box and use not modern gunpowder but old-fashioned blackpowder. This gives a wonderfully rich sound with deep resonance and leaves a nice cloud of smoke hanging around the gun for a few minutes. It is considerably louder than the CCI blank, and for houses of from 200 to 800 seats or more, this is an excellent effect. Blackpowder is much dirtier than modern gunpowder, and the residue is more corrosive than that of regular powder, so scrupulous cleaning after every performance is a must. Winchester periodically threatens to permanently discontinue production of these blanks, and one day they may actually do so.
All .22 blanks are rimfire, meaning that the gun has to strike the edge of the primer, not the center. If you have a .22 caliber centerfire revolver (which would be a real gun, not a starter pistol, so you shouldn’t be using it in a theatre anyway), you’ll need to find specialty .22 caliber centerfire short blanks (very expensive, since they have to be hand loaded and no one wants to handle these tiny things). You can always try to use the rimfire in your centerfire gun, but the misfire rate will be quite high.
There was a time when all ammunition was rimfire, but except for .22 caliber all are now centerfire. Centerfire systems are more reliable than rimfire, and cause less damage to the gun over time. So why are .22’s still rimfire? Because they are tiny cartridges, and it gets really hard to set in a primer on a casing that less than a quarter inch in diameter.
Because rimfire blanks are struck along the edge rather than the center, the hammer strike deforms the shape of the cartridge. For that reason, rimfire cartridges are never reloaded, unlike centerfire cartridges.
Note that the .22’s are designated “short”. The reference is in regard to the length of the brass cartridge. There are .22 caliber long rifle blanks available, but these are too long to fit into the chambers of starter pistols.
• I’m going to repeat myself here to remind you that there is another style of .22 blank that is commonly available in hardware stores. “Power loads” are designed for use in some nail-driving guns and also for a machine called a “decoy launcher” (used for training hunting dogs). These blanks come in different loads and are packaged in different colored boxes to help in distinguish between them. They must never be used in firearms of any kind, real or theatrical. These things are not built to make noise; they’re built to propel an object with far more force than even a real bullet would. The machines that they go into have barrels with very thick walls to be able to withstand the explosion. Your starter pistol doesn’t. The use of these blanks in a starter pistol or stage gun will destroy your gun, and it puts the user and bystanders in danger of being hit by fragments when the pistol finally explodes like a hand grenade. I know that it’s tempting to use them, especially since finding proper blanks can be difficult and these power loads are cheap and right down the street. But don’t do it. Not even once. I once had a beautiful Remington lever-action rifle that had its receiver destroyed by just one shot from one of these “power” loads. If you have some of these in your collection, throw them out.
• 9mm rimmed blanks are made for the Italian 9mm blank-fire revolvers, and are also accurately called .380 blanks, so these can be used in 38 caliber revolvers. [Revolver is the key word, for these blanks do not fit into 9mm semiautomatic pistols.] They come in full and in half load, but again half load does not mean half as loud. The half load cartridge is the same height as the full-load, so the powder is packed more loosely. This means that the powder burns more slowly, so ends up being equivalent in sound to the .22 blackpowder blank. The full load is ten times as loud, and in an indoor theatre it sounds like a cannon going off. It seems to work best for outdoor venues or if you really need to simulate a chest-shaking explosion. Make sure that the actor firing the gun doesn’t have to hear anything you say for about five minutes after firing. Either that or give him full hearing protection.
• There are blanks made for .38 caliber revolvers, but as these are designed for real guns, the casings are too long to fit into theatre starter pistols. A lot of theatres accidentally buy them, and then leave them in the props cabinet for some future props master to deal with. If you have nothing better to do with your time, you can always trim off the excess brass with a small diameter pipe cutter.
• .32 caliber is somewhere in between the loudnesses of .22 and .38 (9mm), and would be a good compromise sound if it weren’t for the scarcity of .32 caliber blank-fire pistols. The blanks are made both by Winchester in a very loud blackpowder version, and in modern “smokeless” powder by Pobjeda/Precise.
• Blank-fire semi-automatic starter pistols are only available in 8mm. The great thing about the 8mm blanks is that they are only made for these pistols, and these pistols can only take these blanks, so no real gun ammunition can ever be accidentally loaded into one. The drawbacks are many: stovepiping, jamming, availability, and that the 8mm blank is extremely loud, almost as much as the 9mm – deafening. Half loads are not available, and would only cause more problems in your gun even if they were.
• Shotgun blanks are readily available in 12 gauge, and the sound is deafeningly loud. Because the casing is made of plastic, it is fairly easy to reduce the load. But an especial care should be taken with shotguns. Shotgun blanks are not made for stage, therefore usually have a lot of inert material that comes out of the barrel, which can be deadly if anyone gets in the way. And that inert material is flammable and can still smolder after landing on the ground, with a very real fire danger. Shotgun blanks have another drawback in that they are the same size and shape as real shotgun shells. It’s only too easy for someone to inadvertently stick a real shotgun cartridge into the replica and end up causing an awful lot of damage.
When a very strong sound is required, obviously the higher calibers can provide enough noise to simulate cannon-fire even in a 2000 seat outdoor amphitheater. The basic equation doesn’t change: more sound means more powder burning and creating more very hot gasses leaving the gun.
As I said, if a gun is chambered for let’s say .45 caliber, it can use only .45 caliber, but can fire effectively with a half or quarter load (or even just the primer with no powder at all) of that same caliber – with one important exception. Semiautomatic pistols and their blank-fire stage equivalents (8mm) require the force of a full-load in order to kick out the spent cartridge and bring up the second round automatically. Reducing the amount of gunpowder in the blank by even a small amount will mean that the gun will fire only once and then have to be reloaded manually for each subsequent shot. For several shots from a semi-auto, it’s full load or nothing. And full load from an 8mm in a small house is simply too much sound. [We’ll talk about the other problems with semi-auto’s in a later section.]
One way to get around that is to use a replica made to look like a semi-auto but really is just an empty casing with a .22-caliber starter pistol revolver inside. It looks close enough like a semi-auto, but since it is really a revolver, it can fire full, half or quarter loads without difficulty.
The quality of the sound produced by any particular blank will vary with each show, for the angles of the set will direct the sound in different directions, and the materials used in construction will either reflect or absorb sound as well. Test fire some blank choices once the set is in place to hear how it affects the house. [Always use ear and eye protection when firing blanks.]
What if the sound is too loud? Well, if you’re not dealing with a semi-automatic (see above), you can try to remove some of the powder within the blank and it won’t affect the performance of the gun. Don’t try to remove the primer; your time is more valuable than that, and you run a high risk of exploding the blank. Instead, simply dig into the other end of the blank with an awl or large nail to create a hole big enough to tap out the amount of powder you want to, then seal it up again. [Because the casing is brass and will not spark, I usually just bore right into the end of the blank using an electric drill, although this freaks everyone out. I consider this relatively safe, since at the very low speed of the drill the brass does not heat up anywhere near the point where it would need to set off the gunpowder, but then again I don’t ask anyone else to do the job for me. I do make sure not to drill all the way down to the primer, which then could indeed ignite from the friction of the drill bit, and that in turn would ignite the powder. This has happened to me once, and I was very grateful for the quality of safety glasses I was wearing]. NOTE: if you seal up the hole on your newly reduced blank with hot glue or rubber cement, expect to clean out the gun a little more aggressively than normal, for you’ll need to clear out the melted plastic from the works.
Tapping out half of the powder will not necessarily mean that you’ll get half of the sound, because the amount of gunpowder is only one variable that determines the amount of sound. For some blanks, the primer itself is so loud that you can tap all of the powder out and still have quite a pop. On others the primer is almost silent. On some blanks the sound volume can be reduced by simply stirring (loosening) the compacted powder and sealing it up again. Experimentation is required, but use safety goggles, ear protection and gloves.
How Loud is Too Loud?
[There is a lot of information below, but I don’t want you to miss the main point. Protect your ears! If a sound causes pain, it is causing damage.]
Below are the results of readings we’ve taken on several of the commercial blanks we’ve provided. When possible, we tested the blanks in three ways:
First we fired the blanks with the decibel meter at a distance of only two feet from the gun. This way we can get an idea of what the shooter experiences when he or she fires the gun with arm outstretched.
Then the same type of blank was fired in a typical blackbox style theatre at a distance of ten feet from the meter. In smaller houses, we figured that this is what another actor sharing the stage, or even the first row of the audience, would hear. Blackbox theatres are not only small, but the sound is also contained – a lot of the sound is bouncing off of the walls and coming right back at the audience, heightening the perceived sound level.
Finally, we shot off some blanks in a 600 seat theatre with the sound meter fifty feet away from the pistol. We were going for “middle-of-the-house” perception. Thinking of it now, it’s a completely arbitrary distance, but there you are. We wanted to demonstrate the effect of the inverse square relationship of sound (if the distance from the source is doubled then the intensity is quartered). But remember that a lot of things affect the sound that reaches the audience’s ears, starting with the shape of the set.
As you can see, the further you are from the gun, the lower the decibel level.
Stage Gunshots:
Percussion cap only
– shooter – 2 ft 85 dB
– blackbox – 10 ft 83 dB
– proscenium – 50 ft 72 dB
Percussion w/ 1 tbsp powder
– shooter – 2 ft 92 dB
– blackbox – 10 ft 88 dB
– proscenium – 50 ft 75 dB
6mm (.22 cal) crimped
– shooter – 2 ft 88 dB
– blackbox – 10 ft 85 dB
– proscenium – 50 ft 75 dB
.22 cal crimped
– shooter – 2 ft 88 dB
– blackbox – 10 ft 87 dB
– proscenium – 50 ft 78 dB
.22 cal blackpowder
– shooter – 2 ft 95 dB
– blackbox – 10 ft 90 dB
– proscenium – 50 ft 85 dB
.32 cal blackpowder
– shooter – 2 ft 115 dB
– blackbox – 10 ft 113 dB
– proscenium – 50 ft 93 dB
9mm (.380 cal) crimped
– shooter – 2 ft 135 dB
– blackbox – 10 ft 128 dB
– proscenium – 50 ft 100 dB
9mm crimped half-load
– shooter – 2 ft 96 dB
– blackbox – 10 ft 93 dB
– proscenium – 50 ft 85 dB
9mm primer only
– shooter – 2 ft 86 dB
– blackbox – 10 ft 85 dB
– proscenium – 50 ft 72 dB
Keep in mind that the decibel system is a logarithmic scale, in this case in multiples of 10, much like the Richter scale for measuring earthquake intensity. Something at the lowest level of hearing perception is designated as 0db, something 10 times as loud as 10db, 100 times as loud is 20db, 1,000 times as loud is 30db, and so on. But that’s not what we perceive. Compared to our other senses, we’re really bad at measuring loudness. We can differentiate between loader and softer, but not in the amount of the difference. The softer 22 caliber blanks are not really all that loud, even in a small theatre. But the suddenness of the sound can still shock the audience … more than the volume. We’ve done decibel checks on both firing live blanks and also taped sound, and found that the audience will perceive a live blank-fire to be louder than even a higher-volume taped gun-shot. I believe that it is because there is a faint background buzz or hum that comes out of the speakers just before the taped sound effect is heard. That faint sound prepares the audience’s hearing, albeit subconsciously, to expect some sort of sound change. Live fire, on the other hand, catches them completely by surprise.
Perceptions of Increases in Decibel Level
“Imperceptible Change” 1 dB about 50% louder
“Barely Perceptible Change” 3 dB about twice as loud
“Clearly Noticeable Change” 5 dB about three times as loud
“About Twice as Loud” 10 dB about ten times as loud
“About Four Times as Loud” 20 dB one hundred times as loud
Since decibel numbers mean nothing without putting them into some sort of context, here are some readings from other sources (measuring sound is notoriously difficult – the same examples from different sources vary by as much as 20 decibels).
Environmental Noise
Whisper (3-5′) 20 dB
Normal conversation (3-5′) 60-70 dB
Busy Street Traffic 75 dB
Telephone dial tone 80 dB
Level at which sustained exposure may result in hearing loss 90 – 95 dB
Average television setting 75 – 95 dB
Power mower 107 dB
Power saw 110 dB
Pain begins 125 dB
Pneumatic riveter at 4′ 125 dB
Noisy squeaky toy at 2′ 135 dB
Jet engine at 100′ 140 dB
full-load 12 gauge shotgun at 2 ft 158 db
“real” pistol shot (.38 – .45 caliber) 154 – 165 dB
Ear drum can perforate 160 dB
Death of hearing tissue 180 dB
Loudest perceived sound possible 194 dB
And keep in mind that gunshots are sound spikes, not sustained sound levels. The longer you are exposed to a loud sound, the more damage it causes. The Occupational Safety and Health Administration has set limits on the level of sound that can be allowed in a workplace, based both on loudness and duration.
OSHA Daily Permissible Noise Level Exposure (hearing protection not required)
Hours per day Sound level
8 90 dB
6 92 dB
4 95 dB
3 97 dB
2 100 dB
1.5 102 dB
1 105 dB
30 minutes 110 dB
15 minutes or less 115 dB
single sound spike 115 dB
What does this all mean? Wear ear protection. Ear plugs are pretty inexpensive, but be sure to read the information that’s on the package before you buy. Different plugs and headphones reduce sound by different amounts, and they are listed as ER-5 to ER-25. The number after the ER- is the amount of decibels that will be reduced when you wear the device. Make sure that the plugs you hand out are enough to reduce the level of anticipated sound to a safe range.
Notice that OSHA does not allow 120 db sound spikes at a work environment unless the workers are adequately protected. Beginning at 125 db, a single sound spike can cause hearing damage. Most of the .22 caliber blanks fall below that threshold, but under the right circumstances can still be painful to the ears. How are you treating your actors?
Black-box theatres
Most theatre throughout the world takes place in spaces that hold fewer than 150 seats. These spaces are usually converted from other uses, but even when built specifically for live performance, they are by their nature intimate spaces with close proximity of the actors to the audience. Projection for the actors is usually not a problem, for every seat can hear every whisper. Imagine what a gunshot sounds like.
Obviously we need to keep the sound as quiet as possible, which means at most using .22 caliber, and the softest variety of those that you can find. Even then, the sound can be so “bright” or “sharp” as to be painful for some listeners. So get creative. Perhaps the sound can come from behind a flat, or from the wings, or piped in from the sound system.
Powerful vibrations caused when a gun is fired:
For every action there is an equal and opposite reaction. In a real gun it means that however much force is transmitted to the bullet, the gun and the shooter have to absorb it on the recoil. That recoil travels in a straight line in the opposite direction of the bullet. Now when you hold most guns, the barrel rides a little higher than your hand. When the shot is fired, the gun wants to move backwards, but the grip gets blocked by the skin between your forefinger and thumb. The barrel still wants to travel backwards, so the gun starts to pivot at your hand. If you have a firm grip on the gun, that’s what makes your hand jump up a bit after the shot. If you don’t have a good grip, the gun merely spins out of your hand and flies over your shoulder (or hits you in the face).
In a block-barreled stage gun, however, the force isn’t even transferred to a bullet, so most of that force is slammed into the gun frame, forward of the blast. That’s why firing a stage gun has almost no recoil – the blast is pushing the gun frame both forward and backward simultaneously. But that abuse causes stress fractures to build up in every part of the gun, far more than a real gun would ever have to endure. On very well-built firearms [those costing over $450] the individual components are of sufficiently strong material to withstand the constant battering. The less expensive guns used for stage simply are not manufactured to such demanding standards, and can be expected to first loosen and then break down simply from normal use. Some of the cheapest barely survive even one production.