Creedmoor Sports is a leading vendor of products for competitive shooters and serious hand-loaders. Along with great gear, Creedmoor Sports provides informative content for its customers. The Creedmoor InfoZone provides Reloading Tips, Gear Reviews, Shooting News, and basic gunsmithing information.
Bill Gravatt, President of Creedmoor Sports, is an expert on reloading processes and gear. He developed many of the popular tools marketed by Sinclair Int’l, and he brings that expertise to Creedmoor Sports. Bill hosts a series of “how-to” videos produced for the Creedmoor InfoZone.
In this video, Bill Gravatt demonstrates several methods to clean your cases. Bill tells us: “Powder residue should be removed before you insert your cases into your reloading dies. There are several ways to clean your cases. Many shooters use a combination of various methods…”
1. Manual Cleaning — You can use 0000 Steel wool for the outside of the case and a Case Neck brush for the inside. A paper towel can remove any remaining residue. This is a handy way to clean if you load at the range.
2. Vibratory Tumbling — This traditional method works well, particularly for pistol brass. Experiment with both Corn Cob and Walnut media. You can get a brighter shine by putting a small amount of liquid brass polish in the media.
3. Wet Tumbling with Stainless Media — This process can get your brass clean inside and out. Do check to ensure no pins are stuck in the flash-holes. Watch for peening of case mouths that can occur over time.
4. Ultrasonic Cleaning — Ultrasonic cleaning works great for small parts as well as brass. The ultrasonic process removes all carbon and traces of lube, which can leave the inside of case necks too dry. To smooth bullet seating, try putting a tablespoon of Ballistol in the cleaning solution.
Cleaning Reloading Dies
Cleaning your reloading dies is something that many hand-loaders neglect. In this 60-second Tech Tip, Bill Gravatt provides some smart advice on cleaning your dies. Bill notes: “After heavy use, case lube and carbon can build up in your reloading dies. It’s important to keep them clean. Also, with new dies, give them a good cleaning before first use, because they ship with a corrosion inhibitor.”
1. Step 1 — Prior to cleaning, disassemble the die and spray it with a good degreaser. Do this with brand new dies too.
2. Step 2 – Take a patch and run it in the die to remove old lube and gunk. Don’t forget the decapping assembly and other internal parts.
3. Step 3 — After cleaning the die, but before reassembly, spray the die with a good corrosion inhibitor, such as Corrosion-X or Starrett M1.
When shooting groups at long range on paper it can be difficult to distinguish which bullet holes belong to a particular sequence of shots. If, for example, you shot three 5-shot groups at 600+ yards on a paper target, you would have 15 bullet holes on the target (assuming no misses). But at that distance it would be difficult to see the holes on target (even with a spotting scope). Accordingly, when you inspected the target up close, it would be hard to tell which shots belonged to which group. You might have a vague idea, but couldn’t be sure, without a target camera recording the shot sequence.
Here is a method to separate multiple shots into specific groups so you can better evaluate your load and shooting skills. The trick is pretty simple — mark your bullets with a color from a Sharpie or other felt marking pen. If you are shooting three 5-shot groups, mark five with red, five with green, and five with blue (or purple). Then, when you inspect the target, you can identify the group placements by the colors that appear on the paper.
Round Robin: Using colors you can shoot “Round-Robin” to evaluate seating depths, neck tension, or other variables without having the shot order (and barrel heating) affect group sizes unequally. For example you might have three different neck tensions, each marked with a different color on the bullets. Then shoot Red, Blue, Green in that sequence for five total shots per color.
Smart Tip to Show Colors More Vividly
If the bullet inks are not showing up on your target paper clearly, here is a simple trick that can make the colors “bleed” to be more visible. In your range kit, bring some alcohol solution along with some Q-tips. Then dab the shots on the paper target lightly with wet Q-Tips. Here is the front of a target before and after application of alcohol:
Forum Member NewbieShooter explains: “Dabbing a bit of alcohol on the bullet holes with Q-Tips makes the color pop a bit… especially on the back side.” See below:
In short order you will see the colors spread into the paper, clearly marking the shot holes by distinguishing colors. If you were shooting a dark bullseye, view the the BACK side of the target to see the colors on a light background.
Credits: Bullet Tips photo by Forum Member Dave Way; Target photos by Forum Member NewbieShooter; Story tip from Boyd Allen.
Tumblers and walnut/corncob media are old school. These days many shooters prefer processing brass rapidly with an ultrasonic cleaning machine. When used with the proper solution, a good ultrasonic cleaning machine can quickly remove remove dust, carbon, oil, and powder residue from your cartridge brass. The ultrasonic process will clean the inside of the cases, and even the primer pockets. Tumbling works well too, but for really dirty brass, ultrasonic cleaning may be a wise choice.
Our friend Gavin Gear has evaluated an RCBS Ultrasonic cleaning machine using RCBS Ultrasonic Case Cleaning Solution (RCBS #87058). To provide a real challenge, Gavin used some very dull and greasy milsurp brass: “I bought a huge lot of military once-fired 7.52x51mm brass (fired in a machine gun) that I’ve been slowly prepping for my DPMS LR-308B AR-10 style rifle. Some of this brass was fully prepped (sized/de-primed, trimmed, case mouths chamfered, primer pockets reamed) but it was gunked up with lube and looking dingy.”
UltimateReloader.com Case Cleaning Video (7.5 minutes):
Gavin describes the cleaning exercise step-by-step on UltimateReloader.com. Read Gavin’s Cartridge Cleaning Article to learn how he mixed the solution, activated the heater, and cycled the machine for 30 minutes. As you can see in the video above, the results were impressive. If you have never cleaned brass with ultrasound before, you should definitely watch Gavin’s 7.5-minute video — it provides many useful tips and shows the cleaning operation in progress from start to finish.
Ultra Dry Necks After Ultrasonic Cleaning — Some Suggestions
The Ultrasonic cleaning process gets cartridge brass so “squeaky clean” that increased force may be required to seat your bullets, or they may “grab” as they go in the necks. To reduce bullet-seating effort, you may benefit from adding a little dry case lube inside the case-neck before loading (use a nylon brush). Another trick is adding a teaspoon of Ballistol lube to the cleaning solution. That provides a trace lubricant inside the necks, but does not interfere with powder ignition in any way.
The latest Gen2 RCBS ultrasonic cleaning machine has a large 6.3-quart capacity. That’s nearly 100% larger than the first generation machine in Gavin’s video. The Gen2 machine, $399.99 on Amazon, features a second ceramic heater and transducer to better clean brass cases and firearm parts. The LED is easily programmable, and the timer can be set for up to 30 minutes of cleaning. The original 3.2 quart-capacity RCBS ultrasonic machine, as shown in Gavin’s video, is still available for $189.99 at Midsouth Shooters.
Modern binoculars and Laser Rangefinders have built-in sensors and microprocessors that can provide ballistics solutions. These work via on-board software as well as systems that talk (via Bluetooth) to a mobile device with a Ballistics App installed. Today we feature an Applied Ballistics Podcast that covers these impressive products with integrated ballistics functionality.
AB Integrated Products and Features In this podcast, Applied Ballistics Founder Bryan Litz and Product Manager Francis Colon answer some of the most common questions received from listeners. They primarily discuss the latest Applied Ballistics integrated devices and highlight their capabilities.
Along with describing the basics of optics and rangefinder products with Applied Ballistics functionality, Bryan and Francis talk about how software can tailor the ballistics output to specific applications and firearms. Francis explains Drop Scale Factor (“DSF”) — a means by which you “train” your solver to match your specific equipment.
NOTE: As we cannot embed the full 42-minute podcast here, you’ll need to go to the Applied Ballistics site to listen. CLICK HERE.
Integrated Solution — Leica LRF and Kestrel with AB Software
This video shows how to pair a Leica Rangemaster 2800.com to a Kestrel Elite 5700. The Leica Rangemaster 2800.com provides the Kestrel with the Range, Firing Direction, and Inclination angle. The Kestrel will then calculate the firing solution and provide that solution on its own display as well as feed that back to the Leica which then displays the hold-over when looking through the Rangefinder. This allows for remote, hands-free operation of the Kestrel in a mount while still being able to see the firing solution in the range finder. NOTE: This is an older video, but similar systems operate with the latest products.
Here are two different bullet types, seated to the same CBTO length, but different COAL. Note the shiny scratches on the bullets made by the comparator tool which indicates a point on the bullet ogive near where the ogive will engage the rifling.
Effects Of Cartridge Over All Length (COAL) And Cartridge Base To Ogive (CBTO) – Part 2 by Bryan Litz forBerger Bullets. Part One of this series focused on the importance of COAL in terms of SAAMI standards, magazine lengths, seating depths, and pressure levels. Another measure of length for loaded ammunition is highly important to precision, namely Cartridge Base to Bullet Ogive Length (CBTO).
Figure 2. Chamber throat geometry showing the bullet jump to the rifling or lands.
Look at Figure 2. Suppose the bullet was seated out of the case to the point where the base of the bullet’s nose (ogive) just contacted the beginning of the riflings (the lands) when the bolt was closed. This bullet seating configuration is referred to as touching the lands, or touching the riflings and is a very important measurement to understand for precision hand-loading. Due to the complex dynamics of internal ballistics which happen in the blink of an eye, the distance a bullet moves out of the case before it engages the riflings is highly critical to precision potential. Therefore, in order to systematically optimize the precision of his handloads, it’s critically important that the precision hand-loader understands how to alter bullet seating depth in relation to the barrel rifling. Part of the required knowledge is understanding how to accurately and repeatably measure the Cartridge Base To Ogive (CBTO) dimension. This is explained in the FULL ARTICLE.
Bryan Litz offers an extended discussion on how to measure CBTO using different tools and methods, including the Hornady OAL gauge. You can read this discussion in the full article found on the Berger Bullets website. CLICK HERE to Read Full Article.
Why Not Use CBTO as a SAAMI Standard?
If CBTO is so important to rifle accuracy, you might ask, “Why is it not listed as the SAAMI spec standard in addition to COAL?” There is one primary reason why it is not listed in the standard. This is the lack of uniformity in bullet nose shapes and measuring devices used to determine CBTO.
Benefits of Having a Uniform CBTO
There is another aspect to knowing your CBTO when checking your COAL as it pertains to performance. With good bullets, tooling, and carefully-prepared cases you can easily achieve a CBTO that varies less than +/- .001″ but your COAL can vary as much as .025″ extreme spread (or more with other brands). This is not necessarily bad and it is much better than the other way around. If you have a CBTO dimension that varies but your COAL dimension is tight (within +/- .002″) then it is most likely that your bullet is bottoming out inside the seater cone on the bullet tip. This is very bad and is to be avoided. It is normal for bullets to have precisely the same nose shape and it is also normal for these same bullets to have nose lengths that can vary as much as .025″.
Summary of Cartridge Base To Ogive (CBTO) Discussion
Here are four important considerations regarding bullet seating depth as it relates to CBTO:
1. CBTO is a critical measurement to understand for handloaders because it’s directly related to precision potential, and you control it by simply setting bullet seating depth.
2. Tools and methods for measuring CBTO vary. Most of the measurement techniques have pitfalls (which may give rise to inconsistent results) that you should understand before starting out.
3. A CBTO that produces the best precision in your rifle may not produce the best precision in someone else’s rifle. Even if you have the same rifle, same bullets, same model of comparator gauges, etc. It’s possible that the gauges are not actually the same, and measurements from one don’t translate to the same dimension for another.
4. Once you find the CBTO that produces the best precision in your rifle, it’s important to allow minimal variation in that dimension when producing quality handloads. This is achieved by using quality bullets, tooling, and properly preparing case mouths and necks for consistent seating.
Are you a do-it-yourself kind of guy with a creative eye? Then you’ll love the FREE Target Generator from the folks at ShooterShed.com. This FREE, interactive webpage allows you to design a variety of fun targets, including grids, benchrest-type Score/Group Shooting targets, sight-in targets, and even playing card targets. Choose the paper size and orientation (vertical or horizontal), then select the number of target elements on the page. For example, you could have four (4) bulls or a dozen playing cards. Then click the Style TAB to choose your target style. Use the OPTIONS TAB to overlay a grid on the target, choose squares or diamonds, or include load information blocks. For bullseye targets, you can control the number, color, and spacing (diameter) of the rings. LINK to TARGET GENERATOR.
QWIK TIP: For Super-Quick Target Creation, click the “Target Style” tab, then select a design from the list on the left. Then go to OPTIONS.
Click the TARGET STYLE TAB to select one of many target styles, including NBRSA Benchrest targets and 20+ types of NRA bullseye targets, scaled to distance:
Benchrest
Bullseye
Shapes
NRA High Power
NRA Pistol
NRA Rimfire
Images
Playing Cards
Load Test Blocks
Creating new targets is fast and easy. No computer graphics skills required! We created this green diamonds grid target in just five minutes using the ShooterShed Target Generator:
And here is a handy target with short-range range Benchrest competition-style box/circle aiming points, along with fields for entry of gun/load data:
The program provides a preview of each target you generate. There are controls to choose border and fill colors. If you like a particular design, save the file, and then print as many targets as you want. Check it out, this program is fun and handy to use. Here are four (4) targets your Editor created just for this article. With a bit of practice, you can be generating your own custom targets in minutes.
About the Creator of the Target Generator
The Target Generator program was created by Rod Brown of Sheridan, Wyoming. Rod tells us: “I build custom rifles… I’ve got a 100-yard range out my back door. I shoot short- and long-range benchrest competitively around the country. I’m a full-time software development consultant and an FFL holder. When I’m not developing custom software for my clients, I’m usually fiddling in the shop, building a custom benchrest rifle, traveling to a match, chambering a barrel, or reloading some ammunition.”
Story tip from Boyd Allen. We welcome reader submissions.
Will you be traveling out of state this spring? Or do you have questions about your own state’s firearms laws? Then you’ll want to have quick access to summaries of gun laws in America’s 50 states. Here’s a very valuable online resource you may want to bookmark.
The NRA-ILA (Institute for Legislative Action) has a great feature on the NRA-ILA’s homepage. There is a pull-down menu that includes all 50 states plus the District of Columbia, New York City, and Guam. This quickly provides a host of legal information for each region you select. From the NRA home page, NRA-ILA.org, you can instantly access a host of information for all 50 states. NOTE: Some of this information is not completely current, so you may want to check with more detailed, up-to-date reference, such as the Legal Heat $10 50 State Guide to Firearms Laws and Regulations (2023 Edition). Most of the information in the book is also available in the FREE Legal Heat Firearms Law APP for Android (Google) smartphones and Android mobile devices. Here are screenshots from the Legal Heat Android App.
Shown below is part of the NRA-ILA’s coverage for Texas. There is a summary of the most important Texas gun laws. Below that is a map showing the states that recognize Texas carry permits.
Today, June 20, 2024 is Summer Solstice, the longest day of the year. And right now the Northeast USA is undergoing a major heatwave. That means “peak heat” summer conditions have arrived already. It’s vitally important to keep your ammo at “normal” temps during the hot summer months. Even if you use “temp-insensitive” powders, studies suggest that pressures can still rise dramatically when the entire cartridge gets hot, possibly because of primer heating.
It’s smart to keep your loaded ammo in an insulated storage unit, possibly with a Blue Ice Cool Pak if you expect it to get quite hot. Don’t leave your ammo in the car or truck — temps can exceed 140° in a vehicle parked in the sun.
The way ambient temperatures, barrel heating, and powder warming can affect cartridge pressures (and hence velocities) was covered in a study Pressure Factors: How Temperature, Powder, and Primer Affect Pressure by Denton Bramwell. In that article, the author used a pressure trace instrument to analyze how temperature affects ammo performance. Bramwell’s tests yielded some fascinating results.
For example, barrel temperature was a key factor: “Both barrel temperature and powder temperature are important variables, and they are not the same variable. If you fail to take barrel temperature into account while doing pressure testing, your test results will be very significantly affected. The effect of barrel temperature is around 204 PSI per F° for the Varget load. If you’re not controlling barrel temperature, you about as well might not bother controlling powder temperature, either. In the cases investigated, barrel temperature is a much stronger variable than powder temperature.”
This Editor had the personal experience of 6mmBR hand-loaded ammo that was allowed to sit in the hot sun for 45 minutes while steel targets were reset. The brass became quite warm to the touch, meaning the casings were well over 120° on the outside. When I then shot this ammo, the bullets impacted well high at 600 yards (compared to earlier in the day). Using a Magnetospeed, I then chron-tested the sun-heated ammo. The hot ammo’s velocity FPS had increased very significantly — all because I had left the ammo out in the hot sun uncovered for 3/4 of an hour.
LESSON: Keep your ammo cool! Keep loaded ammo in the shade, preferably under cover or in an insulated container. You can use a SEALED cool pack inside the container, but we do NOT recommend H20 ice packs. And don’t have the container do double duty for food and beverages.
Powder Heat Sensitivity Comparison Test
Our friend Cal Zant of the Precision Rifle Blog has published a fascinating comparison test of four powders: Hodgdon H4350, Hodgdon Varget, IMR 4451, and IMR 4166. The first two are Hodgdon Extreme powders, while the latter two are part of IMR’s Enduron line of propellants.
The testers measured the velocity of the powders over a wide temperature range, from 25° F to 140° F. Hodgdon H4350 proved to be the most temp stable of the four powders tested. [NOTE: New Alliant Reloder TS 15.5 has also proved very temp stable in AccurateShooter’s range tests.]
Even wonder how a pump shotgun works? Then watch this fascinating video from MidwayUSA. The operation of a pump-action shotgun is illustrated with a special cut-away version of a Winchester Model 12. The shotgun has been modified to reveal the inner workings. This cut-away Model 12 still loads and ejects dummy shells, but you can see how the lugs, slides, locks, ramps, springs and other internal parts work. You’ll be amazed how complicated this old pump-gun is. (The Model 12, Winchester’s first hammerless shotgun, is one of the most popular scatterguns ever made. Over 2,000,000 were sold.)
Skip Ahead to 3:00 to See Cut-Away in Action
To see how the Model 12 works, you can skip forward to the 3:00 minute mark in the video. The first part of the video shows how the Model 12 was “sliced and diced” to expose the inner workings. Larry Potterfield of MidwayUSA explains that “the factories often used cut-aways as sales tools to show how a specific model operated”. In addition the U.S. Military used cut-aways for training purposes.
Here is the cut-away completed. Even the pump grip has been sliced to reveal the inner workings.
A round has been picked up from the feed tube, and then is lifted into the chamber.
Over the past 12 months, this article was one of the TOP 20 most-read Daily Bulletin features. We’re reprising it today for those who may have missed it the first time. The above diagram comes from a TiborasurasRex YouTube Video comparing G1 and G7 BC models. CLICK HERE to watch the video.
The better, up-to-date ballistics programs let you select either G1 or G7 Ballistic Coefficient (BC) values when calculating a trajectory. The ballistic coefficient (BC) of a body is a measure of its ability to overcome air resistance in flight. You’ve probably seen that G7 values are numerically lower than G1 values for the same bullet (typically). But that doesn’t mean you should select a G1 value simply because it is higher.
Some readers are not quite sure about the difference between G1 and G7 models. One forum member wrote us: “I went on the JBM Ballistics website to use the web-based Trajectory Calculator and when I got to the part that gives you a choice to choose between G1 and G7 BC, I was stumped. What determines how, or which one to use?”
The simple answer is the G1 value normally works better for shorter flat-based bullets, while the G7 value should work better for longer, boat-tailed bullets.
G1 vs. G7 Ballistic Coefficients — Which Is Right for You?
G1 and G7 refer both refer to aerodynamic drag models based on particular “standard projectile” shapes. The G1 shape looks like a flat-based bullet. The G7 shape is quite different, and better approximates the geometry of a modern long-range bullet. So, when choosing your drag model, G1 is preferable for flat-based bullets, while G7 is ordinarily a “better fit” for longer, boat-tailed bullets.
Drag Models — G7 is better than G1 for Long-Range Bullets
Many ballistics programs still offer only the default G1 drag model. Bryan Litz, author of Applied Ballistics for Long Range Shooting, believes the G7 standard is preferrable for long-range, low-drag bullets: “Part of the reason there is so much ‘slop’ in advertised BCs is because they’re referenced to the G1 standard which is very speed sensitive. The G7 standard is more appropriate for long range bullets. Here’s the results of my testing on two low-drag, long-range boat-tail bullets, so you can see how the G1 and G7 Ballistic coefficients compare:
G1 BCs, averaged between 1500 fps and 3000 fps:
Berger 180 VLD: 0.659 lb/in²
JLK 180: 0.645 lb/in²
The reason the BC for the JLK is less is mostly because the meplat was significantly larger on the particular lot that I tested (0.075″ vs 0.059″; see attached drawings).
For bullets like these, it’s much better to use the G7 standard. The following BCs are referenced to the G7 standard, and are constant for all speeds.
Many modern ballistics programs, including the free online JBM Ballistics Program, are able to use BCs referenced to G7 standards. When available, these BCs are more appropriate for long range bullets, according to Bryan.
[Editor’s NOTE: BCs are normally reported simply as an 0.XXX number. The lb/in² tag applies to all BCs, but is commonly left off for simplicity.]
This article is copyright 2023 AccurateShooter.com. No 3rd Party republication of this article is allowed without advance approval and payment of licensing fees.
In this podcast, Applied Ballistics Founder Bryan Litz and Product Manager Francis Colon answer some of the most common questions received from listeners. They primarily discuss the latest Applied Ballistics integrated devices and highlight their capabilities. 
Effects Of Cartridge Over All Length (COAL) And Cartridge Base To Ogive (CBTO) – Part 2
The way ambient temperatures, barrel heating, and powder warming can affect cartridge pressures (and hence velocities) was covered in a study Pressure Factors: How Temperature, Powder, and Primer Affect Pressure by Denton Bramwell. In that article, the author used a pressure trace instrument to analyze how temperature affects ammo performance. Bramwell’s tests yielded some fascinating results.
The better, up-to-date ballistics programs let you select either G1 or G7 Ballistic Coefficient (BC) values when calculating a trajectory. The ballistic coefficient (BC) of a body is a measure of its ability to overcome air resistance in flight. You’ve probably seen that G7 values are numerically lower than G1 values for the same bullet (typically). But that doesn’t mean you should select a G1 value simply because it is higher.
Drag Models — G7 is better than G1 for Long-Range Bullets
