Put the same load in a variety of barrels (with the same length and chamberings) and you’ll see a wide variance in muzzle velocity. In fact, it’s not unusual to see up to 100 fps difference from one barrel to the next. We demonstrated this with a comparison test of Lapua factory ammo.
Chron Testing Lapua Factory Ammo
At our Southern California test range some years ago, we chronographed Lapua 105gr 6mmBR factory ammo in three different 8-twist barrels of similar length. The results were fascinating. Lapua specs this ammo at 2790 fps, based on Lapua’s testing with its own 26″ test barrel. We observed a speed variance of 67 fps based on tests with three aftermarket barrels.
Barrel Velocity Variance
Brand ‘S’ and Brand ‘PN’ were pre-fit barrels shot on Savage actions. Brand ‘K’ was fitted to a custom action. All test barrels were throated for the 100-108 grain bullets, though there may have been some slight variances in barrel freebore. With a COAL of 2.330″, the rounds were “jumping” to the rifling in all barrels.
Among the four barrels, Brand ‘PN’ was the fastest at 2824 fps average — 67 fps faster than the slowest barrel. Roughly 10 fps can be attributed to the slightly longer length (27″ vs. 26″), but otherwise this particular barrel was simply faster than the rest. (Click Here for results of 6mmBR Barrel Length Velocity Test).
IMPORTANT: Results Are Barrel-Specific, Not Brand-Specific
These tests demonstrate that the exact same load can perform very differently in different barrels. We aren’t publishing the barrel-makers’ names, because it would be wrong to assume that ‘Brand X’ is always going to be faster than ‘Brand Y’ based on test results from a single barrel. In fact, velocities can vary up to 100 fps with two identical-spec barrels from the SAME manufacturer. That’s right, you can have two 8-twist, 26″ barrels, with the same land-groove configuration and contour, from the same manufacturer, and one can be much faster than another.
Don’t Demand More Than Your Barrel Can Deliver
We often hear guys lament, “I don’t get it… how can you guys get 2900 fps with your 6BRs and I can only get 2840?” The answer may simply be that the barrel is slower than average. If you have a slow barrel, you can try using more powder, but there is a good chance it may never run as fast as an inherently fast barrel. You shouldn’t knock yourself out (and over-stress your brass) trying to duplicate the velocities someone else may be getting. You need to work within the limits of your barrel.
Factory Ammo Provides a Benchmark
If you have a .223 Rem, 6mmBR, .243 Win, 6.5×47 Lapua, 6.5 Creedmoor, 6.5×55, .308 Win, .30-06 Springfield, or .338 LM Rifle, we recommend you buy a box of Lapua factory-loaded ammo. This stuff will shoot great (typically around half-MOA), and it can give you a baseline to determine how your barrel stacks up speedwise. [Editor’s NOTE: The original test was conducted in 2008. The velocity of current-production Lapua factory ammo might be higher or lower, so your results may vary.]
When you complete a new 6mmBR rifle, it’s definitely smart to get a box of the factory ammo and chronograph it. That will immediately give you a good idea whether you have a slow, average, or fast barrel. Then you can set your velocity goals accordingly. For example, if the factory 6BR ammo runs about 2780-2790 fps in your gun, it has an average barrel. If it runs 2820+ in a 26″ barrel (or 2835 fps in a 28″), you’ve got a fast tube.
There is an excellent article about primers on the Shooting Times website. We strongly recommend you read Mysteries And Misconceptions Of The All-Important Primer, written by Allan Jones. Mr. Jones is a bona fide expert — he served as the manager of technical publications for CCI Ammunition and Speer Bullets and Jones authored three editions of the Speer Reloading Manual.
This authoritative Shooting Times article explains the fine points of primer design and construction. Jones also reveals some little-known facts about primers and he corrects common misconceptions. Here are some highlights from the article:
Size Matters
Useful Trivia — even though Small Rifle and Small Pistol primer pockets share the same depth specification, Large Rifle and Large Pistol primers do not. The standard pocket for a Large Pistol primer is somewhat shallower than its Large Rifle counterpart, specifically, 0.008 to 0.009 inch less.
Magnum Primers
There are two ways to make a Magnum primer — either use more of the standard chemical mix to provide a longer-burning flame or change the mix to one with more aggressive burn characteristics. Prior to 1989, CCI used the first option in Magnum Rifle primers. After that, we switched to a mix optimized for spherical propellants that produced a 24% increase in flame temperature and a 16% boost in gas volume.
Foiled Again
Most component primers have a little disk of paper between the anvil and the priming mix. It is called “foil paper” not because it’s made of foil but because it replaces the true metal foil used to seal early percussion caps. The reason this little disk exists is strictly a manufacturing convenience. Wet primer pellets are smaller than the inside diameter of the cup when inserted and must be compacted to achieve their proper diameter and height. Without the foil paper, the wet mix would stick to the compaction pins and jam up the assembly process.
Primer Functionality and Primer Types Compared
This video looks at a variety of primer types from multiple manufacturers, foreign and domestic. The video explains the basics of how primers function, and then explains the key characteristics of standard primers, magnum primers, and mil-spec primers (designed for semi-auto rifles).
Father’s Day is Sunday, June 15, 2025. Many leading vendors are running Father’s Day sales and promotions. You’ll find major savings — up to 45% — on a wide selection of products. Scopes, reloading tools, dies, ammo, and reloading supplies are marked down this week. And there are deals on rifles, pistols, and shotguns.
Powder Valley Outdoors
Powder Valley Outdoors is running a major sale this week, June 10-15. There are discounts on ammo from Federal, CCI, Remington, Hornady, Barnes (and other mfgs.) with savings up to 39%. In addition, Hornady brass and reloading tools are on sale. From the Powder Valley Sale Page (left column) you can select the type of product and the manufacturer.
Palmetto State Armory
Palmetto State Armory (PSA) is running a Major Father’s Day Sale. A huge selection of products are on sale including AR uppers, AR lowers, complete rifles, handguns, scopes, ammo, triggers, magazines, and more. Shown below are four of the hundreds of sale items.
EuroOptic.com
If you need a scope, rangefinder, or a new hunting rifle, head over to EuroOptic.com this week. There are major deals on products from a dozen companies. There are great deals on optics from Sightron, Leupold, SIG Sauer, Eotech, and Meprolight with savings up to 45%. In addition, a wide range of firearms (rifles, pistols, shotguns) are discounted this week. There is also a Father’s Day Giveaway contest with the winner getting a new CZ Shadow 2 pistol valued at $1,449.00.
MidwayUSA Sales
MidwayUSA has some great items on sale as part of a Father’s Day Gearing Up Sale. In addition, there is FREE SHIPPING with orders over $99 (Code FS060325). Here are six noteworthy deals from MidwayUSA offered this week. There are hundreds of other bargains.
Brownells Specials This Week
Brownells is also running a sale this week, but not specifically for Father’s Day. There’s a large selection of products on sale right now including magazines, triggers, dies, cleaning rods, ammo, and even the popular Garmin Xero C1 chronograph. CLICK HERE to view all items on sale (2562 total as this is released).
Here’s a cool tool for your hand-loaders, particularly if you load large quantities of bulk ammo for a variety of firearms. Lyman’s handy Ammo Checkers check the diameters of reloaded rounds and factory ammo, so you can quickly confirm that your ammo fits a standard chamber. Just drop your loaded rounds in the Ammo Checker, and if the round fits into the gauge, it will fit in the gun’s chamber.
Lyman Ammo Checkers are multi-caliber — each orange block checks six or eight different cartridge types, with each caliber/cartridge name engraved on the gauge. Ammo Checkers are machined to SAAMI minimum chamber dimensions from solid blocks of 6061 T6 aluminum. Ammo Checkers are available in three versions covering most common handgun and rifle calibers:
Handgun Ammo Checker (#7833000) $32.99 on Amazon
Fits: 380 Auto, 9mm Luger, 38 Super, 40 S&W, 45 ACP, 38/357, 44 Spl/Mag, and 45 Colt
Why Use a Case Gauge?
We find that case gauges like the Lyman Ammo Checker are particularly useful for handgun reloaders using progressive presses. The chambers of many popular semi-auto pistols are partly unsupported. This allows the case to swell in the bottom quarter. The case may not be sized adequately by your sizing die, which can lead to misfeeds or malfunctions.
Additionally, if you have loaded a large quantity of ammo for a semi-auto rifle such as an AR15, it’s not a bad idea to check your cartridges before you load them into your magazines. All you need is one mis-sized round to cause a stoppage. That will ruin your day if you are competing in a Service Rifle match or 3-Gun event.
This USAMU article explores three different “Philosophies” of precision reloading. Some handloaders seek to produce ammo that yields the very tightest groups (without factoring in the wind). Other shooters load their ammo to deliver the highest safe velocity. That’s because a projectile launched at higher velocity will drift less in the wind. The theory is that even if fast ammo doesn’t produce the tightest groups in zero wind conditions, it will yield higher scores in a the real world (where the wind blows). Lastly, some handloaders favor ammo that is ultra-consistent across a wide temperature range. This last philosophy dictates selection of a powder that is temp-insensitive, even if it may not produce the very best raw accuracy (or speed).
What’s Your Handloading Philosophy?
Objectives of Reloading — Accuracy, Velocity, Temp Stability What do you, the reader, primarily value in your handloads?
Viewpoint ONE: Accuracy Trumps Everything
Some shooters prize consistent, excellent medium/long range accuracy enough that they’re willing to give up some extra velocity (and reduced wind deflection) to obtain that. Their underlying philosophy could be stated: “Superior accuracy is present for every shot, but the wind isn’t”. One’s ability to hold well, aim well and read the wind are all factors in making this type decision. The photo below shows stellar raw accuracy. This is an 0.67″, 10-shot group at 300-yards fired from a text fixture. The group measures just 0.67″. (This shows the USAMU’s 600-yard load with 75gr bullets).
Viewpoint TWO: Load to Highest Safe Velocity for Less Wind Drift
Some shooters value obtaining the highest safe velocity, even if one’s pure, consistent mechanical accuracy at medium/long range isn’t quite as brilliant. The theory here seems to be that a really good hold extracts as much mechanical accuracy from the rifle/ammo as possible, and faster bullets equal occasional “bonus” points snatched from the jaws of wind.
[For example] one of the USAMU’s many Service Rifle National Champions revealed his philosophy. It can be stated thus: a super-accurate, but [relatively] “slow” load “required him to have a Ph.D. in wind reading for every shot, while a faster, but less accurate load netted him more points.”
Note — this was not mere speculation; his score book data backed up his claims, due to less wind effects. Remember, however, this fellow has a consistent, National Championship-level hold, and other Champions on the same team would have opted differently.
Viewpoint THREE: Temperature Stability Is Key
Still another approach is to place heavy emphasis on fine accuracy with absolute stability in changing temperatures. When this writer was actively earning his Distinguished Rifleman badge, that was his goal. The reason? Sighting shots are not allowed in EIC (“Leg”) matches. The first shot out of the barrel was for score. It had to be 100% consistent, with very reliable, predictable elevation and wind deflection regardless of the ambient temperature — even if it wasn’t the lowest wind deflection possible.
Naturally, selecting a powder that is insensitive to temperature changes is a key element here. Elevation zeros and wind effects HAD to be consistent every time. Hunters and military snipers might be among those who fall into this camp, as well as those in pursuit of their Distinguished Rifleman badges.
Contrast that with a traditional High Power shooter who gets two sighter shots before each event (offhand, sitting rapid, prone rapid, prone slow fire.) If there is a zero change on any given day, he/she can correct during sighters. This writer well remembers talking with another very high-level Service Rifle competitor who was happy to have high temperatures boost the velocities of his ammunition above their usual level… As far as this SR competitor was concerned, 60-80 fps more velocity -– even if only due to high ambient temperatures -– meant less wind deflection, and he was mighty happy to have it.
Particularly in the summer, with hot daily conditions, you need to be concerned about temperature stability. Loads worked up in winter may not work in the summer time.
This article has been confined to NRA High Power Rifle competition, which has relatively generous 10-ring dimensions in relation to the accuracy of well-built competition rifles. Hopefully, it will provide food for thought. For some, this might be an opportunity to ensure that one’s load development approach helps them attain their desired results.
Precision Benchrest and F-Class shooters favor premium brass from Lapua, Norma, Peterson, or RWS. (Lake City also makes quality brass in military calibers.) Premium brass delivers better accuracy, more consistent velocities, and longer life. Shooters understand the importance of good brass, but many of us have no idea how cartridge cases are actually made. Here’s how it’s done.
The process starts with a brass disk stamped from strips of metal. Then, through a series of stages, the brass is extruded or drawn into a cylindrical shape. In the extrusion process the brass is squeezed through a die under tremendous pressure. This is repeated two or three times typically. In the more traditional “draw” process, the case is progressively stretched longer, in 3 to 5 stages, using a series of high-pressure rams forcing the brass into a form die. While extrusion may be more common today, RWS, which makes some of the most uniform brass in the world, still uses the draw process: “It starts with cup drawing after the bands have been punched out. RWS cases are drawn in three ‘stages’ and after each draw they are annealed, pickled, rinsed and subjected to further quality improvement measures. This achieves specific hardening of the brass cases and increases their resistance to extraordinary stresses.” FYI, Lapua also uses a traditional draw process to manufacture most of its cartridge brass (although Lapua employs some proprietary steps that are different from RWS’s methods).
After the cases are extruded or drawn to max length, the cases are trimmed and the neck/shoulder are formed. Then the extractor groove (on rimless cases) is formed or machined, and the primer pocket is created in the base. One way to form the primer pocket is to use a hardened steel plug called a “bunter”. In the photos below you see the stages for forming a 20mm cannon case (courtesy OldAmmo.com), along with bunters used for Lake City rifle brass. This illustrates the draw process (as opposed to extrusion). The process of draw-forming rifle brass is that same as for this 20mm shell, just on a smaller scale.
River Valley Ordnance explains: “When a case is being made, it is drawn to its final draw length, with the diameter being slightly smaller than needed. At this point in its life, the head of the draw is slightly rounded, and there are no provisions for a primer. So the final drawn cases are trimmed to length, then run into the head bunter. A punch, ground to the intended contours for the inside of the case, pushes the draw into a cylindrical die and holds it in place while another punch rams into the case from the other end, mashing the bottom flat. That secondary ram holds the headstamp bunter punch.
This video employs DEFORM-2D software to show the draw process for brass casings.
The headstamp bunter punch has a protrusion on the end to make the primer pocket, and has raised lettering around the face to form the headstamp writing. This is, of course, all a mirror image of the finished case head. Small cases, such as 5.56×45, can be headed with a single strike. Larger cases, like 7.62×51 and 50 BMG, need to be struck once to form a dent for the primer pocket, then a second strike to finish the pocket, flatten the head, and imprint the writing. This second strike works the brass to harden it so it will support the pressure of firing.”
Thanks to Guy Hildebrand, of the Cartridge Collectors’ Exchange, OldAmmo.com, for providing this 20mm Draw Set photo. Bunter photo from River Valley Ordnance.
For load development, some guys shoot 3-shot groups. Other guys shoot 5-shot groups, or even 10-shot strings. But for testing its projectiles, Sierra Bullets takes it to another level entirely. A while back Sierra was testing its .30-Caliber 175gr HPBT MatchKing in the Sierra underground tunnel. The results appear above — a FIVE HUNDRED Round group!
500 Shots Form 0.82 MOA Group at 300m (328 yards)
Sierra’s trigger-pullers sent five full boxes of bullets down-range at a single target. The photo above shows the result of 500 shots taken in a 300 meter test tunnel. The raw group size, edge to edge of the farthest shots, is about 3.13 inches, as shown on the calipers’ metal linear scale. Subtract a .308″ nominal bullet diameter* to get the 2.823″ on the digital readout. So you’re seeing a 2.823″ group at 300 meters (328 yards). One MOA at this distance is 3.435″ so this 500-round group is 2.823 divided by 3.435 or 0.82 MOA (0.8218 MOA to be precise).
This 500-round group was shoot as part of a pressure/velocity test for a commercial customer. The cartridge was .308 Winchester, loaded at 2.800″. The powder was Reloder 15. A 26″ barrel was shot from a return to battery rest. The gun was cleaned every 125 rounds and two foulers shot.
What do you think — could you beat this group from a bench for 500 rounds?
One Facebook poster joked: “500-round group? Everyone knows anything less than 1000-round groups are a waste of time and statistically irrelevant.”
Sierra’s 300 Meter Testing Tunnel
Ever wonder how (and where) Sierra tests its bullets? The answer is underground, in a 300-meter test tunnel located under Sierra’s factory in Sedalia, Missouri. The photo above shows the construction of the tunnel back in May, 1990. Like most bullet manufacturers, Sierra does live-fire bullet testing of its projectiles. Sierra’s 300-meter test range is the longest, manufacturer-owned underground bullet test facility in the world. In years past, Sierra offered free visits to the test tunnel as part of a factory tour.
* Normally, to get an exact group size, you should subtract the TRUE bullet hole size, which is usually smaller than the nominal bullet diameter. E.g. a .308 bullet hole may show on paper as .298 or so. But here, for simplicity, we are subtracting .308″ because we do not have the original target to measure.
Here’s a simple task you can do that will give your seater die a more perfect fit to your match bullets. You can lap the inside of the seater stem so that it matches the exact profile of the bullet. This spreads out the seating force over a larger area of the bullet jacket. That allows smoother, more consistent seating, without putting dents, creases, or sharp rings in your bullets.
This process is demonstrated here by our friend Erik Cortina of Team Lapua-Brux-Borden. Erik, one of the nation’s top F-Class shooters and a skilled machinist, explains: “Here I’m lapping my new seater die stem with lapping compound. I chuck up a bullet in the lathe and lap the inside of the seating stem. I put lapping compound on the bullet and also in the stem. You can do the same with a hand drill and bore paste. You can see in the piture below how much contact area the stem has on the bullet after being lapped. This bullet is a Berger 7mm 180-grain Hybrid. ”
It can be helpful but it’s not necessary to make your seating stem an exact match to a bullet, particularly if you’re loading hunting or varmint rounds. But it is helpful to do some mild internal stem polishing. This should eliminate any ring (or dent) that forms on the bullet jacket during seating.
Sharp edges on a seating stem can cause a ring to be pressed into the bullet jacket — especially with compressed loads that resist downward bullet movement.
Q2: Is there any down-side to the process?
Not really. However, if you shoot many different bullet types for a particular cartridge, you may not want to conform the stem aggressively to one particular bullet design. Lightly lap the inside of the stem to remove burrs/sharp edges but leave it at that. A light lap will prevent a ring forming when seating bullets.
At the request of our readers, we provide select “Deals of the Week”. Every Sunday afternoon or Monday morning we offer our Best Bargain selections. Here are some of the best deals on firearms, hardware, reloading components, optics, and shooting accessories. Be aware that sale prices are subject to change, and once clearance inventory is sold, it’s gone for good. You snooze you lose.
NOTE: All listed products are for sale to persons 18 years of age or older. No products are intended for use by minors.
Excellent vendor EuroOptic.com is running a major clearance sale this week on big name optics. You can save hundreds on quality scopes from Vortex, Leupold, Burris, Pulsar, Athlon, Schmidt & Bender, Swarovski and more. Click these links for the optics Clearance Sales by manufacturers: Vortex| Leupold | Burris | Athlon | Schmidt & Bender | Pulsar
⏺️ » Great package for just $11 more than Chrono alone
Right now you can get the Garmin Xero C1 Pro Chronograph by itself for $549.99 at many vendors. However, for just $11 more ($560.99 total) you can get a Garmin Xero C1 Pro Package complete with tripod, charging accessories, and more. This $560.99 package includes Garmin Xero C1 Pro Chronograph, USB Charging Adapters, White Cube, 6Ave Microfiber Cleaning Cloth, USB Car Adapter, P-Bank Battery, 72 Inch Pro Heavy-Duty Aluminum Tripod. That’s a great deal.
⏺️ » Great combo offer for FFP scope and good laser rangefinder
Here’s a good Scope/Rangefinder combo package for PRS/NRL shooters and varmint hunters. For just $499.99 ($200 off) you get both scope and rangefinder. The Vortex 5-25x56mm Venom scope has First Focal Plane EBR-7C MOA reticle, 34mm tube for ample turret travel, and RevStop Zero System. This is a good FFP optic for folks who prefer MOA clicks. The Vortex Crossfire HD 1400 Laser Rangefinder features an HD optical system, three target modes, and red TOLED display. Vortex states this LRF “ranges deer up to 750 yards, trees up to 950 yards, and reflective targets up to 1400 yards.”
4. Midsouth — Sale on Hornady Tools and Accessories
⏺️ » Nearly all Hornady dies, tool and products on sale this week
⏺️ Nice pair of Walkie-Talkie Muffs that can be recharged
Here’s a great item for buddies or family members who hunt together or compete in pair matches. MidwayUSA is offering a matched pair of Walker’s FireMax Rechargeable Muffs for just $159.99, 66% Off MSRP. You never need to buy batteries — these run for 150 hours after charging with a standard USB-C cable. These NRR20 muffs have comfortable Gel earpads and omni-directional microphones. This combo pack includes two earmuffs and two detachable Walkie Talkie units. The Walkie Talkies offer 4 Frequency modes: Universal, Clear Voice, High-Frequency, Power Boost.
If you are looking for a good, tough 12ga defensive shotgun, here’s a fantastic deal. The Citadel Mariner 12ga pump-action shotgun features a durable nickel finish and barrel heat-shield. It comes complete with front and rear sights, an optics rail, plus a shotshell carrier on the left side of the action. This cool pump shotgun is now just $174.91 on sale — an amazing deal, $104 off the normal price.
7. Midsouth — Summer Clearance Sale, up to 50% Off
⏺️ » Huge savings on reloading kits, ammo, and other gear
Midsouth is running a major Summer Clearance Sale right now, with discounts up to 50%. There are major savings on ammo, reloading presses, gun cases and more. For example, you can save $100 on a LEE Six Pack Pro 6000 progressive press with FREE shipping.
⏺️ Excellent, rugged rifle case at a very good price
When flying or driving it’s vital to protect your rifles. A good hard case option (at a great price) is the APACHE 9800 Weatherproof Protective Rifle Case. On sale for $149.99, this 53″-long case is $190.00 less than an equivalent-size Pelican case. Constructed from durable polypropylene, this quality hard case can protect long guns from from impact, moisture, and dust. The built-in purge valve equalizes pressure so you can open the case after changing elevations. NOTE: Case interior dimensions are 50⅜” by 13⅝”.
9. Midsouth — Lee Challenger Press with BONUS Die Set, $83.99
⏺️ » Get good single-stage press AND die set
The LEE Challenger is the world’s best-selling single station press. The latest Gen III Challenger features an ergonomic lever plus convenient drop-tube for spent primers. Right now LEE is offering a FREE carbide die set with the purchase of the LEE Gen III Challenger Press. Chose one of five cartridge types: .223 Rem, 9mm Luger, .38 SPL/.357 Mag, .44 SPL/.44 Mag, and .45 ACP. Another good feature of the LEE Press is the Breech Lock Quick Change Die System — change dies instantly with a twist of the wrist.
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Photos and Facebook post by Tactical Rifle Shooters
Yet another .300 Blackout disaster. Unfortunately, that .300 Blackout cartridge can fit in a .223 Rem chamber. Shooting a .308-caliber bullet in .223 bore is a recipe for disaster.
The .300 AAC Blackout aka “300 BLK”, is a compact 30-caliber cartridge designed to work in AR-15 rifles. It has a shorter cartridge case to accommodate the bigger 30-caliber bullet while still fitting in a standard AR-15 magazine. Unfortunately, that’s the danger. A careless shooter can toss a .300 Blackout cartridge in with .223 Rem rounds without noting. And because the case-head size is the same as the .223 Rem (5.56×45) the rifle’s bolt assembly will happily chamber and fire the .300 BLK round. Problem is, that forces a .308 diameter bullet down an undersized .223-caliber bore. Not good!
This images were provided by Tactical Rifle Shooters on Facebook. The message was clear: “Don’t try to run 300 Blackout in your .223/5.56mm. It won’t end well. The problem is identical rifles and identical magazines but different calibers.”
Image from Accurate Shooter Forum. Cutaway shows the jammed .30-Cal bullet:
For those who MUST have a .300 Blackout, here are some things you can do:
1. Use different colored magazines for .300 Blackout vs. .223 Rem.
2. Fit all your uppers with caliber-labeled ejection port covers.
3. Mark .223 Rem upper handguards with the caliber in bright paint.
4. Mark all .300 BLK Rounds with heavy black marker.
Comments by Folks Who Viewed these .300 Blackout Disaster Photos:
“The .300 Blackout is simply a badly-designed round. A properly-designed round would have had a feature in the shape that would have prevented cross loading in the first place.” — D. Santiago
“I almost made that mistake… I had a magazine of 300 BLK inserted in my .223/5.56 all night. Fortunately, I never pulled the trigger. Once I realized the mistake, I almost got ill. [After that incident] I no longer own a 300 BLK.” — B. Welch
“Happened to me hog hunting from a helo. Gun exploded in my face.” — B. Hood
“Fire-forming projectiles [is] so wrong in centerfire!” — M. Stres
“Had some dude come into the store the other day wanting .300 Blackout ammo to shoot in his 5.56 AR. It took 15 minutes of explaining for him to understand you got to have a .300 Blackout Upper!” — R. Williams
Barrel Velocity Variance
Precision Benchrest and F-Class shooters favor premium brass from 
The headstamp bunter punch has a protrusion on the end to make the primer pocket, and has raised lettering around the face to form the headstamp writing. This is, of course, all a mirror image of the finished case head. Small cases, such as 5.56×45, can be headed with a single strike. Larger cases, like 7.62×51 and 50 BMG, need to be struck once to form a dent for the primer pocket, then a second strike to finish the pocket, flatten the head, and imprint the writing. This second strike works the brass to harden it so it will support the pressure of firing.”
The 
