Our friend Dennis Santiago was recently conducting training for a Southern California Police Department. During a training session one of the unit’s AR15s stopped functioning. The problem — the bolt in the AR rifle broke in half. Dennis states: “They ran the gun dry, broke for lunch, shot it again. They don’t like that. I personally like to flood the bolt wet with lube on training days. It prevents stuff like this. Given that, it’s a simple remove-and-replace fix.”
Here are some of the more interesting comments about this parts failure — an AR bolt that literally sheared in half:
“If I was a betting man [the steel] wasn’t made by Carpenter Steel. They are one of the few companies that use the correct [milspec-steel, C-158] called out on the drawing which they coincidentally developed. Most of the other companies that make [AR Bolts] use different steel with the same heat treat specification as what is called out which gives them the potential of being a little on the brittle side at the upper end of the tolerance. When it comes to the AR platform, bolts are probably the only part of the entire gun where I must admit to being a little bit of a brand snob.” David O’N.
[Editor’s Note: Actually Carpenter Steel does not make AR bolts. They are a steel supplier, and yes Carpenter did develop the original C-158 steel for AR bolts. Here is a contrary view, claiming that AISI 9310 Steel is actually stronger than milspec Carpenter C-158: 9310 Steel for AR Bolts.]
“Dry bolt and carrier shouldn’t cause that. Looks like a big pressure spike. What kind of ammo…?” Guy G.
Reply from Dennis: “55gr factory ammo.Piles of it.”
“Is that the new two-piece bolt everyone’s been talking about LOL?” — Darren R.
“Let me guess…the PD called you in cause they didn’t know why it stopped going ‘pew pew’?” — Jim O.
Reply from Dennis: “I was there today for qualifications. It broke during the rifle phase. Simple enough to fish the bolt parts out of the action. The training didn’t miss a beat. I have an armory full of the things.”
CCI and Federal Premium are both brands of Vista Outdoor. Most CCI rimfire is produced in Idaho, while other Federal-branded rimfire ammo is produced in Federal’s Anoka, Minnesota facilities. Here we feature videos from both CCI and Federal ammo plants. Watch and learn how rimfire ammo is made.
Field & Stream Tours Federal Ammo Plant in Minnesota
A reporter for Field & Stream recently got a chance to tour the Federal ammunition production facility in Anoka, Minnesota. This large plant produces both rimfire and centerfire ammunition. While touring the plant, the reporter was allowed to capture video showing the creation of .22 LR rounds from start to finish. This is a fascinating video, well worth watching.
Note to Viewers — After Starting Video, Click Speaker Icon to HEAR audio!
This revealing video shows all phases of .22 LR ammo production including cupping, drawing, annealing, washing, drying, head-stamping, priming, powder charging, bullet seating, crimping, waxing, inspection, and final packaging. We recommend you watch the video from start to finish. You’ll definitely learn some new things about rimfire ammo.
.22 LR Ammo Production in Idaho
Back in 2016, YouTuber 22Plinkster was able to tour the CCI Ammo plant in Lewiston, Idado. Here is the rimfire production video he produced.
The Manufacturing Process for .22 LR Rimfire Ammunition Shooting Sports USA explains: “Rimfire cartridge cases are the oldest self-contained cartridge in existence, having been in continuous production since the mid-1850s. Rimfire cases are drawn from a thin piece of brass and formed with a hollow rim. A priming compound is then forced into the case using centrifugal force, where it is charged with powder and a bullet is seated in the mouth of the case. The case is then crimped around the bullet to ensure sufficient push and pull when the round is fired. When the firing pin strikes the thin brass rim of the case, the hollow rim is crushed and the primer is ignited.” Source: SSUSA.org 9/2/2017.
Why You CANNOT Rely on the MV Printed on the Ammo Box!
When figuring out your come-ups with a ballistics solver or drop chart it’s “mission critical” to have an accurate muzzle velocity (MV). When shooting factory ammo, it’s tempting to use the manufacturer-provided MV which may be printed on the package. That’s not such a great idea says Bryan Litz of Applied Ballistics. Don’t rely on the MV on the box, Bryan advises — you should take out your chrono and run your own velocity tests. There are a number of reasons why the MV values on ammo packaging may be inaccurate. Below is a discussion of factory ammo MV from the Applied Ballistics Facebook Page.
Five Reasons You Cannot Trust the Velocity on a Box of Ammo:
1. You have no idea about the rifle used for the MV test.
2. You have no idea what atmospheric conditions were during testing, and yes it matters a lot.
3. You have no idea of the SD for the factory ammo, and how the manufacturer derived the MV from that SD. (Marketing plays a role here).
4. You have no idea of the precision and quality of chronograph(s) used for velocity testing.
5. You have no idea if the manufacturer used the raw velocity, or back-calculated the MV. The BC used to back track that data is also unknown.
1. The factory test rifle and your rifle are not the same. Aside from having a different chamber, and possibly barrel length some other things are important too like the barrel twist rate, and how much wear was in the barrel. Was it just recently cleaned, has it ever been cleaned? You simply don’t know anything about the rifle used in testing.
2. Temperature and Humidity conditions may be quite different (than during testing). Temperature has a physical effect on powder, which changes how it burns. Couple this with the fact that different powders can vary in temp-stability quite a bit. You just don’t know what the conditions at the time of testing were. Also a lot of factory ammunition is loaded with powder that is meter friendly. Meter friendly can often times be ball powder, which is less temperature stable than stick powder often times.
3. The ammo’s Standard Deviation (SD) is unknown. You will often notice that while MV is often listed on ammo packages, Standard Deviation (normally) is not. It is not uncommon for factory ammunition to have an SD of 18 or higher. Sometimes as high as 40+. As such is the nature of metering powder. With marketing in mind, did they pick the high, low, or average end of the SD? We really don’t know. You won’t either until you test it for yourself. For hand-loaded ammo, to be considered around 10 fps or less. Having a high SD is often the nature of metered powder and factory loads. The image below is from Modern Advancements in Long Range Shooting: Volume II.
4. You don’t know how MV was measured. What chronograph system did the manufacturer use, and how did they back track to a muzzle velocity? A chronograph does not measure true velocity at the muzzle; it simply measures velocity at the location it is sitting. So you need to back-calculate the distance from the chrono to the end of the barrel. This calculation requires a semi-accurate BC. So whose BC was used to back track to the muzzle or did the manufacturer even do that? Did they simply print the numbers displayed by the chronograph? What kind of chronograph setup did they use? We know from our Lab Testing that not all chronographs are created equal. Without knowing what chronograph was used, you have no idea the quality of the measurement. See: Applied Ballistics Chronograph Chapter Excerpt.
5. The MV data may not be current. Does the manufacturer update that data for every lot? Or is it the same data from years ago? Some manufacturers rarely if ever re-test and update information. Some update it every lot (ABM Ammo is actually tested every single lot for 1% consistency). Without knowing this information, you could be using data for years ago.
CONCLUSION: Never use the printed MV off a box of ammo as anything more than a starting point, there are too many factors to account for. You must always either test for the MV with a chronograph, or use carefully obtained, live fire data. When you are using a Ballistic Solver such as the AB Apps or Devices integrated with AB, you need to know the MV to an accuracy down to 5 fps. The more reliable the MV number, the better your ballistics solutions.
We know you guys like taking photos of your rifles at the range. And, if you’re selling a rifle, scope, front rest, or rear bag, you need good photos to post in our Forum classifieds. Here’s a basic photography tip that can help you produce dramatically better photos. Use your camera’s ability to add “fill flash” even in daylight.
There’s plenty of light on a bright day. But bright light also means strong shadows. The shadows can leave parts of your subject literally in the dark. Daylight flash will help fill in those dark spots. In addition, if you are on a covered firing area, and want to include the range in your photo, you can benefit from using flash. This will prevent the foreground subject from being too dark while the downrange background is much too bright.
Photo without Flash
The photo above was taken without flash. As you can see, the rifle is too dark so details are lost. At the same time, the background (downrange) is over-exposed and washed out. The second photo below is taken with daylight flash. The difference is dramatic. Now you can see details of the rifle, while the background is exposed properly. Note how much easier it is to see the the targets downrange and the colors of the front rest. NOTE: these two photos were taken at the same time — just seconds apart.
Photo with Daylight “Fill-Flash”
Be sure to click on the larger versions of each photo.
How to Activate Daylight Flash
Most digital cameras have daylight flash capability. Some cameras have a separate setting for “auto fill flash”. On other cameras, you’ll have to set the camera to aperture priority and stop down the aperture to force the flash to fire. Read your camera’s manual. On many Canons, a menu that lets you set the “flash output”. For “fill flash” we like to set the flash at 30% to 50% output. This fills in the shadows sufficiently without “killing contrast” or creating too much reflection on shiny metal. Below is a photo taken with 30% flash output. Note the rich colors and how the exposure is balanced between foreground and background. Without flash the sky and target area would be “washed out”.
Here’s another tip for Canon owners. If you like deep, rich colors, use the “Vivid” setting in the effects menu. This punches up saturation and contrast.
SUMMARY: Powder can have a very long shelf life. You need to watch for changes in smell and color. A reddish tinge, almost like rust on the powder, is a bad sign, as is a foul odor, not to be confused with a normal chemical smell. Either of these signs indicate it is time to dispose of your powder by means other than shooting.
Ever wondered about the stability of the propellants in your reloading room? There are some important things you should know about powder storage, to ensure consistent powder performance and safety. On its website, Western Powders (vendors of Accurate, Norma, and Ramshot powders) published an informative Q & A series entitled Dear Labby: Questions for our Ballistics Lab. Here are some excerpts that pertain to powder storage and shelf life. Worried that your powder may be too old? Western’s experts explain how to check your propellants for warning signs.
Proper Powder Storage
Q: I live in southern Arizona where it is very hot. I am told powders will become unstable if stored in an area not air-conditioned. My wife says no powder or primers in the house. Can powder be stored in a refrigerator? What about using a fireproof safe? I would appreciate your ideas. — M.C.
Lab Answer: SAAMI guidelines are pretty clear on issues of storage. They recommend storing smokeless powder in containers that will not allow pressure to build if the powder is ignited — ruling out gun safes and refrigerators.
In their original containers smokeless powder’s lifespan is quite long, even in your hot, arid climate, typically longer than the average handloader would need to store them. Stored safely in a garage or outbuilding, your powder should last years. If you see the powder developing a reddish tint, or giving off a foul odor, it is time to discard it.
Clumps in Powder Container
Q: I ordered some of your Accurate 1680 powder back about in December. I just now opened it … and it is full of clumps. My knowledge tells me that means moisture. Am I wrong? I just now broke the seal and it has been stored in a ammo can with desiccant packs around it and a dehumidifier running 14-16 hours a day. I can’t imagine this being my fault, if this does indicate moisture. I don’t know if the pink part on the label is suppose to be red or not, but it is definitely pink, so if it was red I am wondering if I was shipped an old container? I hope that this isn’t bad and I am stuck with it…
Lab Answer: All powder contains a certain amount of moisture. When the powder is stored or during shipping, it can go through temperature cycles. During the cycling, the moisture can be pulled to the surface and cause clumping. Clumping can also be caused by static electricity if too dry or the powder has limited graphite content. You can break up the clumps before metering and they shouldn’t be a problem. This will not affect the powder performance, so your product is fine. Accurate 1680 labels are designed in Pink. As a side note, specification for testing powder is at 70° F and 60% humidity.
There is nothing more frustrating (or embarassing) than sending a live round into your expensive new chronograph. As the photo below demonstrates, with most types of chronographs (other than the barrel-hung Magnetospeed), you can fatally injure your expensive chrono if it is not positioned precisely.
When setting up a chrono, we always unload the rifle, remove the bolt and bore-sight to ensure that the path of the bullet is not too low. When bore-sighting visually, set up the rifle securely on the sandbags and look through the bore, breech to muzzle, lining up the barrel with your aim point on the target. Then (during an appropriate cease-fire), walk behind the chronograph. Looking straight back through the “V” formed by the sky-screens, you should be able to see light at the end of the barrel if the gun is positioned correctly. You can also use an in-chamber, laser bore-sighter to confirm the visual boresighting (see photo).
Adjust the height, angle and horizontal position of the chronograph so the bullet will pass through the middle of the “V” below the plastic diffusers, no less than 5″ above the light sensors. We put tape on the front sky-screen supports to make it easier to determine the right height over the light sensors.
Use a Test Backer to Confirm Your Bullet Trajectory
You can put tape on the support rods about 6″ up from the unit. This helps you judge the correct vertical height when setting up your rifle on the bags. Another trick is to hang a sheet of paper from the rear skyscreen and then use a laser boresighter to shine a dot on the paper (with the gun planted steady front and rear). This should give you a good idea (within an inch or so) of the bullet’s actual flight path through the “V” over the light sensors. Of course, when using a laser, never look directly at the laser! Instead shine the laser away from you and see where it appears on the paper.
Alignment of Chronograph Housing
Make sure the chrono housing is parallel to the path of the bullet. Don’t worry if the unit is not parallel to the ground surface. What you want is the bullet to pass over both front and rear sensors at the same height. Don’t try to set the chrono height in reference to the lens of your scope–as it sits 1″ to 2″ above your bore axis. To avoid muzzle blast interference, set your chronograph at least 10 feet from the end of the muzzle (or the distance recommended by the manufacturer).
Rifles with Elevated Iron Sights
All too often rookie AR15 shooters forget that AR sights are positioned roughly 2.4″ above the bore axis (at the top of the front sight blade). If you set your bullet pass-through point using your AR’s front sight, the bullet will actually be traveling 2.4″ lower as it goes through the chrono. That’s why we recommend bore-sighting and setting the bullet travel point about 5-8″ above the base of the sky-screen support shafts. (Or the vertical distance the chronograph maker otherwise recommends). NOTE: You can make the same mistake on a scoped rifle if the scope is set on very tall rings, so the center of the cross-hairs is much higher than the bore axis line.
TARGET AIM POINT: When doing chrono work, we suggest you shoot at a single aiming point no more than 2″ in diameter (on your target paper). Use that aiming point when aligning your chrono with your rifle’s bore. If you use a 2″ bright orange dot, you should be able to see that through the bore at 100 yards. Using a single 2″ target reduces the chance of a screen hit as you shift points of aim. If you shoot at multiple target dots, place them in a vertical line, and bore sight on the lowest dot. Always set your chron height to set safe clearance for the LOWEST target dot, and then work upwards only.
Other Chronograph Tips from Forum Members:
When using a chronograph, I put a strip of masking tape across the far end of the skyscreens about two-thirds of the way up. This gives me a good aiming or bore-sighting reference that’s well away from the pricey bits. I learned that one the hard way. — GS Arizona
A very easy and simple tool to help you set up the chronograph is a simple piece of string! Set your gun (unloaded of course) on the rest and sight your target. Tie one end of the string to the rear scope ring or mount, then pull the string along the barrel to simulate the bullet path. With the string showing the bullet’s path, you can then easily set the chronograph’s placement left/right, and up/down. This will also let you set the chrono’s tilt angle and orientation so the sensors are correctly aligned with the bullet path. — Wayne Shaw
If shooting over a chrono from the prone position off a bipod or similar, beware of the muzzle sinking as recoil causes the front of the rifle to drop. I “killed” my first chronograph shooting off a gravel covered firing point where I’d not given enough clearance to start with and an inch or two drop in the muzzle caused a bullet to clip the housing. — Laurie Holland
The Berger SW Nationals is coming up in a couple weeks. At that match, the sling shooters and F-Class competitors need to haul lots of gear from parking lot to the firing line, and then move from yardage to yardage. Along with their rifles, shooters need to bring mats, front rests or bipods, spotting scopes (with stands), rear bags, ammo boxes, log sheets, tool kits, and heavy coats (for the sling shooters).
To do the hauling, you can certainly purchase a factory-made, purpose-built cart that folds up and has all the bells and whistles. The Creedmoor Sports CRC-1 (photo right) is a proven, quality product that works great. You’ll find these used by top shooters at Camp Perry. But the Creedmoor CRC-1 cart costs $499.95. For a fraction of that price ($55.99), plus a few dollars more for do-it-yourself enhancements, you can have a heavy-duty cart that will haul all your gear just fine, though it doesn’t fold up. In the top photo is a Harbor Freight Welding Cart we saw at the Berger Southwest Nationals. This rig is carrying a rifle in hard gun case, bipod, folding chair, shooting mat, tripod, spotting scope, rear sand-bag, and ammo box — that’s a lot of gear!
Check out the Harbor Freight Welding Cart, item #65939. This cart is ON SALE right now for just $59.99. Overall size is 29-1/2″ L x 20″ W x 49″ H, and width between side rails is 18″. The wheels (with tires) are 20 3/4″ in diameter for smooth rolling. Consider that, if you made your own cart from scratch you could easily pay $30.00 or more just for the large-diameter wheels and axle. Do note — this cart has air-filled tires. Be sure to inflate before you go to the Range!
This Cart is now on sale for just $55.99 — GREAT DEAL!
As sold, the Harbor Freight Welding Cart can benefit from upgrades for range use. But with a few bungee cords (and some creativity), the cart can be adapted pretty easily to hauling your gun gear. If you want to enhance the basic cart, it’s easy to add plastic side-panels on the bottom unit, and fit a barrel-holding system on the cross-tube. This ensures rifles and gear won’t flop forward. (A small piece of wood under the bottom panel provides a bit of extra lift that will keep the bottom plate out of the dirt and gravel.)
This helpful video from our friend Kirsten Joy Weiss explains how to avoid “scope bite”. This can occur when the scope, on recoil, moves back to contact your forehead, brow, or eye socket area. That’s not fun. While common sense tells us to avoid “scope bite” — sooner or later this happens to most shooters. One viewer noted: “I have come close. I had a Win Model 70 in .375 H & H Mag and I was shooting over a large rock in a strange position. The scope hit my eye glasses hard enough to bend the wire frames and cause a little pain on the bridge of the nose from the nose piece. [That] made a believer out of me.”
Kirsten offers a good basic principle — she suggests that you mount your rifle-scope so that the ocular (eyepiece) of the scope is positioned at least three inches or more from your eyeball when you hold the rifle in your normal shooting position. From a technical standpoint, optical eye relief is a property of the scope, so you want to purchase an optic that offers sufficient optical eye relief (meaning that it allows you to see the full circle of light with your head at least three inches from the eyepiece). Then you need to position the optic optimally for your head/eye position when shooting the rifle — with at least three inches of eyeball-to-scope separation (i.e. physical eye relief).
NOTE: You should mount the scope to provide adequate eyeball-to-scope separation for the actual position(s) you will be shooting most of the time. For an F-TR rig, this will be prone. For a hunting rifle, your most common position could be sitting or standing. Your head position will vary based on the position. You can’t assume the scope placement is correct just because it seems OK when you are testing or zeroing the gun from the bench. When shooting from a prone or kneeling position you may find your eye considerably closer to the eyepiece.
Don’t have time to neck-turn hundreds of cases? Don’t want to invest in your own annealer? Want to try a Dasher or 6 BRA but don’t like the hassle of fire-forming? Then give Darrell Jones at DJ’s Brass a call at 205-461-4680. He can handle all the difficult brass forming/brass restoration chores efficiently and affordably. And Darrell’s turn-around time is typically very fast.
Hydro-Forming News — .284 Shehane, 6 PPC, 6 BRA, 6 Dasher and More
NEW for 2019! Darrell also just got a custom hydro die for the .284 Shehane, a wildcat based on the .284 Winchester. This is a very popular option for F-Open Shooters. He is also doing a ton of fire-forming for the 100/200 benchrest crowd, hydro-forming 220 Russian into 6 PPC. And he tells us “Those guys in Montana are keeping me very busying hydro-forming the 6BR Ackley (6 BRA). NOTE: Darrell offers Free Annealing with hydro-forming services, which starts at $60 per 100 cases.
With the price of premium brass topping $1.00 per case for popular match cartridges, it makes sense to consider annealing your brass to extend its useful life. You don’t want to chuck out brass that costs a buck a case (or more)! Forum member Darrell Jones offers a full range of brass prep, brass forming, and brass restoration (annealing, ultra-sonic cleaning) at very affordable prices. Starting at just $20 per 100 cases ($25/100 for magnum cases), Darrell’s company, DJ’s Brass, will anneal your used brass using the impressive Bench-Source annealing machines. Annealing plus ultrasonic cleaning starts at $35 per 100 cases ($45 for magnum cases). For a bit more money Darrell can also uniform the primer pockets and chamfer the case necks.
Custom Neck-Turning Services
Another great service DJ’s Brass provides is precision neck-turning. Darrell can neck-turn any size case to your specified neck-wall thickness. The price starts at $60.00 per hundred for standard cases or $75.00/100 for magnum size. And if you’ve got a bucket of brass to neck-turn, that’s fine with Darrell — he recently neck-turned 1500 pieces of brass for one customer!
DJ’s Brass can process everything from .17 Fireball all the way up to the big magnum cases. And the job gets done quickly. Darrell normally offers a 10-day turn-around. For most jobs, Darrell tells us, he gets the processed brass to the Post Office within three business days. For more info, visit DJsBrass.com or call Darrell Jones at 205-461-4680. IMPORTANT: Contact Darrell for shipping instructions BEFORE sending any brass for processing. ALL BRASS MUST BE DE-PRIMED before you send it.
• Anneal Case Necks Only ($20.00/100 normal or $25.00/100 magnum)
• Ultrasonic Cleaning, Check Necks, and Annealing ($35.00/100 normal or $45.00/100 magnum)
• Full Service: Uniform primer pockets, Chamfer case mouths, Ultrasonic cleaning, Anneal case necks (Starting at $60.00/100 call for quote)
• Neck Turning or trim-to-length Custom Order Service (Starting at $60.00/100 for standard cases and $75.00/100 for magnums)
• Hydro-Form Specialty cases (such as Dasher) $0.60 (sixty cents) each minimum of 100 pieces plus actual return shipping cost
• Expand Case Necks and Anneal brass (Call for Price)
• Create False Shoulder for Fire-Forming (Call for Price)
Hydro-Forming Cartridge Brass
Hydro-forming by Darrell costs $0.60 per case with 100-ct minimum. All hydro-formed cases are annealed at no extra charge after the forming process. After hydro-forming, Darrell can also neck-turn the case for an additional charge (call for combined quote). In addition to the 6mmBR-based cases shown below, Darrell can now hydro-form 6PPC cases from .220 Russian brass, and he also offers .284 Shehane.
With Darrell’s hydro-forming service you don’t have to buy any special dies or other equipment. Darrell says: “Simply send me the brass you need or have it dropped-shipped to me along with a fired case that has not been sized. If you need formed brass for a new build (gun not yet fired), let me know and I will size the brass to fit within .001″ of a PT&G GO gauge.”
DJ’s Brass Offers Specialized Custom Services
Darrell tells us: “At DJ’s Brass, we can handle all your brass refurbishing needs. From ultrasonic cleaning to custom annealing for specific wildcat cartridges. We can expand your necks from .22 caliber to .30 caliber and anneal shoulders for consistent bump-back. We can turn your case-necks and trim the brass to your specs. For some cartridge types, I can pre-form cases to assist in fire-forming a wildcat cartridge. We also remove the carbon build-up in muzzle brakes. Don’t lose your accuracy by having carbon build up and close off the clearance required for the most accurate bullet release through a muzzle brake.” Note: Extra charges apply for neck-turning and neck expansion operations, or specialized cartridge-forming operations. Please call Darrell at 205-461-4680 for special services pricing.
OK, you’ve paid the tax stamp and acquired your new suppressor (aka “silencer” or “moderator”). Do you still need to wear earplugs or muffs? Absolutely. Even with that expensive new “can”, your rifle could be generating over 140 decibels (dB) of noise — about the same as as an unmuffled 9mm pistol shot. That’s loud enough to create permanent hearing loss with repeated exposure.
Firearms Are Loud: 140 dB to 175 dB
Audiology group ASHA explains: “Exposure to noise greater than 140 dB can permanently damage hearing. Almost all firearms create noise that is over the 140-dB level. A small .22-caliber rifle can produce noise around 140 dB, while big-bore rifles and pistols can produce sound over 175 dB. Firing guns in a place where sounds can reverberate, or bounce off walls and other structures, can make noises louder and increase the risk of hearing loss. Also, adding muzzle brakes or other modifications can make the firearm louder. People who do not wear hearing protection while shooting can suffer a severe hearing loss with as little as one shot[.] Audiologists see this often, especially during hunting season when hunters and bystanders may be exposed to rapid fire from big-bore rifles, shotguns, or pistols.” Source: ASHA, Recreational Firearm Noise Exposure.
Suppressors, On Average, Reduce Noise Levels about 30 Decibels
In an article for Ammoland, gunwriter Sam Hoober says that you can expect about 30 decibels (dB) of noise reduction from the average suppressor: “Looking at a few different products, SilencerCo attests their suppressors reduce the sound pressure of a 9mm gunshot to anywhere from 125.7 dB to 131.5 dB, depending on the model. Advanced Armament Co, another popular supplier, attests a 23 dB to 33 dB reduction or down to 127 dB. Liberty Suppressors, another manufacturer, attests a reduction of 24 dB to 38 dB, depending on model and other factors. In short, we can presume something on the order of 30 dB of attenuation as an average.”
Using that 30 dB number you can quickly discern that you’ll still need hearing protection — good hearing protection — when shooting any suppressed firearm (even a .22 LR). “Spikes of 130 dB and more can result in permanent hearing damage instantly”. Source: NRA Blog.
The Myth of the “Quiet” .22 LR
The NRA Blog notes that “many rimfire shooters, particularly those using the beloved .22 Long Rifle cartridge, argue that the small .22 LR caliber doesn’t produce enough sound to damage your hearing”. So, is that really true. or is it a myth?
In fact, a .22 LR can be much louder than you think — a .22 LR pistol can produce sound levels of 134 dB. That’s well above the normal human pain threshhold.
Sound Levels for Common Noises:
9mm Luger pistol: 160 dB
Jet aircraft engine (near): 140 dB
.22 LR pistol: 134 dB
Normal human pain threshold: 120 dB
Noisy Nightclub: 110 db
Riding Motorcycle at 65 mph: 103 db
Power Lawnmower: 95 dB
Hearing damage possible: 85 dB (sustained for 8+ hours)
Ringing Telephone: 80 dB
Normal conversation: 60 dB
The Risk of Hearing Loss
Hearing loss can be progressive and irreversible. If you are a shooter, this is serious business. As the NRA Blog cautions: “You may not even realize you’re harming your hearing. Hearing loss occurs gradually, and can go effectively unnoticed until symptoms become severe. By then, the damage is done.”
Nobody wants to go deaf. But we often see shooters without effective hearing protection when they are walking around a few yards behind the firing line. That’s bad — even if you are away from the firing line, gunshot noises can damage your hearing. You MUST use effective hearing protection every time you go to the range. Good foam earplugs costs mere pennies but they can prevent deafness in your later years. Many folks also wear muffs over plugs.
We know you guys like taking photos of your rifles at the range. And, if you’re selling a rifle, scope, front rest, or rear bag, you need good photos to post in our Forum classifieds. Here’s a basic photography tip that can help you produce dramatically better photos. Use your camera’s ability to add “fill flash” even in daylight.
When setting up a chrono, we always unload the rifle, remove the bolt and bore-sight to ensure that the path of the bullet is not too low. When bore-sighting visually, set up the rifle securely on the sandbags and look through the bore, breech to muzzle, lining up the barrel with your aim point on the target. Then (during an appropriate cease-fire), walk behind the chronograph. Looking straight back through the “V” formed by the sky-screens, you should be able to see light at the end of the barrel if the gun is positioned correctly. You can also use an in-chamber, laser bore-sighter to confirm the visual boresighting (see photo).
The Berger SW Nationals is coming up in a couple weeks. At that match, the sling shooters and F-Class competitors need to haul lots of gear from parking lot to the firing line, and then move from yardage to yardage. Along with their rifles, shooters need to bring mats, front rests or bipods, spotting scopes (with stands), rear bags, ammo boxes, log sheets, tool kits, and heavy coats (for the sling shooters).
With the price of premium brass topping $1.00 per case for popular match cartridges, it makes sense to consider annealing your brass to extend its useful life. You don’t want to chuck out brass that costs a buck a case (or more)! Forum member 
The Risk of Hearing Loss
