When neck-turning cases, it’s a good idea to extend the cut slightly below the neck-shoulder junction. This helps keep neck tension more uniform after repeated firings, by preventing a build-up of brass where the neck meets the shoulder. One of our Forum members, Craig from Ireland, a self-declared “neck-turning novice”, was having some problems turning brass for his 20 Tactical cases. He was correctly attempting to continue the cut slightly past the neck-shoulder junction, but he was concerned that brass was being removed too far down the shoulder.
Craig writes: “Everywhere I have read about neck turning, [it says] you need to cut slightly into the neck/shoulder junction to stop doughnutting. I completely understand this but I cant seem to get my neck-turning tool set-up to just touch the neck/shoulder junction. It either just doesn’t touch [the shoulder] or cuts nearly the whole shoulder and that just looks very messy. No matter how I adjust the mandrel to set how far down the neck it cuts, it either doesn’t touch it or it cuts far too much. I think it may relate to the bevel on the cutter in my neck-turning tool…”
Looking at Craig’s pictures, we’d agree that he didn’t need to cut so far down into the shoulder. There is a simple solution for this situation. Craig is using a neck-turning tool with a rather shallow cutter bevel angle. This 20-degree angle is set up as “universal geometry” that will work with any shoulder angle. Unfortunately, as you work the cutter down the neck, a shallow angled-cutter tip such as this will remove brass fairly far down. You only want to extend the cut about 1/32 of an inch past the neck-shoulder junction. This is enough to eliminate brass build-up at the base of the neck that can cause doughnuts to form.
The answer here is simply to use a cutter tip with a wider angle — 30 to 40 degrees. The cutter for the K&M neck-turning tool (above) has a shorter bevel that better matches a 30° shoulder. There is also a 40° tip available. PMA Tool and 21st Century Shooting also offer carbide cutters with a variety of bevel angles to exactly match your case shoulder angle*. WalkerTexasRanger reports: “I went to a 40-degree cutter head just to address this same issue, and I have been much happier with the results. The 40-degree heads are available from Sinclair Int’l for $15 or so.” Forum Member CBonner concurs: “I had the same problem with my 7WSM… The 40-degree cutter was the answer.” Below is Sinclair’s 40° Cutter for its NT-series neck-turning tools. Item NT3140, this 40° Cutter sells for $14.99. For the same price, Sinclair also sells the conventional 30° Cutter, item NT3100.
Al Nyhus has another clever solution: “The best way I’ve found to get around this problem is to get an extra shell holder and face it off .020-.025 and then run the cases into the sizing die. This will push the shoulder back .020-.025. Then you neck turn down to the ‘new’ neck/shoulder junction and simply stop there. Fireforming the cases by seating the bullets hard into the lands will blow the shoulder forward and the extra neck length you turned by having the shoulder set back will now be blended perfectly into the shoulder. The results are a case that perfectly fits the chamber and zero donuts.”
* 21st Century sells carbide cutters in: 15, 17, 20, 21.5, 23, 25, 28, 30, 35, 40, and 46 degrees. PMA Tool sells carbide cutters in: 17.5, 20, 21.5, 23, 25, 28, 30, and 40 degrees, plus special short-neck cutters.
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 recently put an RCBS Ultrasonic cleaning machine through its paces 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 percent larger than the first generation machine in Gavin’s video. The Gen2 machine, $322.02 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 $166.56 at Midsouth Shooters.
Chances are that many of you have packed away your ammo and shooting supplies for the winter. Maybe you put your brass in a storage bin that might also contain solvents, old rags, or used bore swabs. Well, if you use any ammonia-based solvents, we suggest you separate the brass and ammo and keep it away from potential ammonia vapors. This is because long-term exposure to ammonia fumes can cause cracks to form in your brass. This can lead to case ruptures and possible injury.
This case-cracking phenomenon has been called Season Cracking, a form of stress-corrosion cracking of brass cartridge cases. Season cracking is characterized by deep brittle cracks which penetrate into affected components. If the cracks reach a critical size, the component can suddenly fracture, sometimes with disastrous results. If the concentration of ammonia is very high, then corrosion is much more severe, and damage over all exposed surfaces occurs. The brass cracking is caused by a reaction between ammonia and copper that forms the cuprammonium ion, Cu(NH3)4, a chemical complex which is water-soluble. The problem of cracking can also occur in copper and copper alloys such as bronze.
Season Cracking was originally observed by the British forces in India a century ago. During the monsoon season, military activity was reduced, and ammunition was stored in stables until the dry weather returned. Many brass cartridges were subsequently found to be cracked, especially where the case was crimped to the bullet. In 1921, in the Journal of the Institute of Metals, the phenomenon was explained by Moor, Beckinsale, and Mallinson. Apparently ammonia from horse urine, combined with the residual stress in the cold-drawn metal of the cartridges, was responsible for the cracking.
Don’t store ammunition (or brass) for long periods in a box or container holding ammoniated solvents:
The Australia Department of Defense (AUSDOD) has also explored the problem of brass cracking caused, at least in part, by exposure to ammonia. A study was done to see whether the amount of cracking (from ammonia exposure) varied according to the duration and temperature of the annealing process used on the brass. CLICK HERE to read AUSDOD Research Report.
Story idea from Boyd Allen. We welcome reader submissions.
He who dies with the most toys wins — right? Well Sinclair has another interesting gadget you can add to your reloading bench. The Sinclair Case Neck Sorting Tool lets you quickly sort brass by neck-wall thickness. For those who shoot “no-turn” brass, this can improve neck-tension consistency. Large variances in neck-wall thickness can cause inconsistent neck “grip” on the bullet. Generally, we’ve found that more consistent neck tension will lower ES and (usually) improve accuracy. We know some guys who shoot no-turn 6mmBR brass in competition with considerable success — but their secret is pre-sorting their brass by neck-wall thickness. Cases that are out-of-spec are set aside for sighters (or are later skim-turned).
Watch Case Neck Sorting Tool Operation in Video
How the Case Neck Sorting Tool Works
Here’s how the Sinclair tool works. Cases are rotated under an indicator tip while they are supported on a case-neck pilot and a support pin through the flash hole. The unit has a nice, wide base and low profile so it is stable in use. The tool works for .22 through .45 caliber cases and can be used on .17- and .20-caliber cases with the optional carbide alignment rod. The MIC-4 pin fits both .060 (PPC size) and .080 (standard size) flash holes. Sinclair’s Case Neck Sorting Tool can be ordered with or without a dial indicator. The basic unit without dial indicator (item 749-006-612WB) is priced at $59.99. You can also buy the tool complete with dial indicator (item 749-007-129WB) for $89.99. IMPORTANT: This sorting tool requires caliber-specific Case Neck Pilots which must be ordered separately.
Editor’s Comment: The purpose of this Sinclair tool is rapid, high-quantity sorting of cartridge brass to ascertain significant case-neck-wall thickness variations. Consider this a rapid culling/sorting tool. If you are turning your necks, you will still need a quality ball micrometer tool to measure neck-wall thickness (to .0005) before and after neck-turning operations.
The Giraud power trimmer indexes off the shoulder of the case. It is costly, but offers high production rates, trimming to length and chamfering in one operation.
The folks at PMA Tool, makers of arbor presses, neck-turning tools, and other case-prep tools, offer some good advice about case trimming on the PMA Tool Blog. Here we reprint a PMA blog post that explains case trimming basics and helps you choose the right case-trimming tool for your needs.
Case Trimming Basics
Trimming the cartridge case to the proper length is a crucial step in case preparation that should not be overlooked or underestimated. The cartridge case or the rifle can be damaged, or even worse you get badly injured. In most instances cases should be trimmed after firing and sizing. Trimming new brass is necessary for a lot of wildcats and can be beneficial in some instances, but by and large, trimming new brass is not necessary for most situations (unless you are neck-turning). Cases should be trimmed after you have sized the case, because the expander ball on the decapping pin can (and will) stretch the neck. Those of us who neck size should get into the habit of trimming after sizing as well. This is a good rule of thumb to go by, and hopefully it will keep you safe during the reloading and shooting process.
There are so many case trimmers out there that work, deciding which one is right for you can be confusing. Even though I have trimmed thousands of cases, using about every method possible, I can’t answer the question of what case trimmer is right for you because of all the variables that may be involved. I can, however shed some light on the subject.
The two most popular designs of trimmers either index (1) off the base or the head of the case, (2) off the shoulder or datum line of the case. There are pros and cons to each and it all depends on what you are willing to live with.
Indexing off the Base (Case Head)
Let’s talk about the first one I have listed, indexing off the base, or the head of the case. The pros to this method are that you can achieve a very accurate over all length and that is after all, what it is all about. The cons to this method are that you can get some variation doing it this way. Let me explain, the base is not always square to the body or can be damaged during firing especially if it is fired through a military style rifle with a very aggressive ejector. These cases should be discarded, but sometimes they can be overlooked. This condition can lead to an over all length that is incorrect. The case head being out of square will be corrected upon firing, however that case will wind up being shorter than the rest of your cases, possibly creating a difference in the neck tension on the bullet. The more you can do to eliminate variables in your reloads the better off you are going to be. This method can also be very slow, and if the user gets careless the result will be a inconsistent over all length.
Indexing off the Shoulder (Datum Line)
The second method I mentioned, trimming off the shoulder or the datum line of the case, has its pros as well. I have found this to be the quickest of the methods and very accurate as well. After the case has been sized through the die the dimensions (particularly the headspace) of the cases are usually very uniform and exact, this allows the case to be trimmed by indexing off the shoulder. This method can be done very quickly, by hand, or by powering either the case, or the trimmer. You also don’t have to worry about the case heads being out of square with the body using this method. Generally the trimming time is cut in half, and this leads to greater focus on the job, without becoming careless.
The PMA Micro-Adjust Case Trimmer indexes case length off of the shoulder of a properly fire-formed and full-length re-sized case. We accomplish this through the use of interchangeable Delrin™ inserts which capture the shoulder and neck of the case. This insert is contained in a spring-loaded tool head that rides on a linear bearing. When the case is captured within the tool head the tool head rotates along with the case, the spring allows for the case to self-align squarely to the cutter and allows you to control the feed rate into the cutter.
— Indexes off shoulder for easy, consistent trim length
— Fully rotating head with bearing for smooth operation keeps cuts square
— Large, ergonomic design fits the hand well
— Sharp carbide cutter for quick, smooth cuts with minimal bur
— Cases captured in Delrin™ (completely non-marring material)
— Spring loaded head allows complete control of rate of feed.
Our trimmer can be used in three ways. The first method utilizes our PMA Tool caseholder drivers and your power screwdriver, drill, case lathe, drill press or lathe. Trimming via this method the case is spun and fed into the trimmer while it is held in your hand. In the second method, the trimmer’s adjustment knob is removed (after adjusting and locking the setting) and the cutting shaft is chucked in a drill, drill press or lathe. Using this method, the case itself is held by hand and fed into the cutter. We’ve found this to be the quickest method to trim.
Summary
The choice is yours to make. I hope that this was some help to you, whether you are looking for your first trimmer or looking to replace the trimmer you have. Just remember to always put safety first and accuracy second, and you will start making little bug holes in no time.
Story Tip by EdLongrange. User submissions are welcome.
Who doesn’t want to save money? If you can get a significant discount, you should really take advantage of that opportunity. Guys, we’ve been tracking prices on shooting sports products at vendors around the country. Sad to say, we’ve seen price increases across the board in 2019. Reloading components, loading tools, stocks, targets, electronic gadgets — you name it, the price trend is moving upwards. Thankfully our friends at Precision Reloading are holding the line. Even better, Precision Reloading is running a really significant promotion right now.
Take Note! For today and tomorrow, January 16 and January 17, you can get 15% OFF All ORDERS over $100.00. That’s right, save 15% on your purchases at Precision Reloading with Code 15OFF. If you buy a $400.00 item that could save you $60.00. Yes, this applies to pretty much everything in stock at Precision Reloading, including all major brands below (and dozens more including Lapua, Berger, Forster, Hodgdon, Nosler, RCBS, Redding, Sierra etc.).
If you need bullets, brass, powder, dies, presses, powder dispensers, check out this sale. It’s a very good deal. Use Code 15OFF at check-out to save 15% on your orders over $100.00.
In this video, gunsmith Alex Wheeler explains how to ensure that your full-length sizing dies fit your brass properly. With many cartridge types, it’s not unusual for factory dies to be slightly large in the bottom section. When the diameter of a FL-sizing die is too large near the base, this can leave the bottom section of fired cases “unsized”, with the result that you can have extraction issues and stiff bolt lift, or what Alex calls “clickers”. At the same time, it’s not unusual for dies to over-size fired cases at the shoulder (i.e. reduce the shoulder diameter by .004″ or more).
We strongly recommend that all hand-loaders watch this video, particularly if you load cases 6+ times with relatively high-pressure loads.
Alex explains that a key dimension is the diameter of a fired case 0.200″ above the case head. If your die does not size your fired cases at this point, you should get a FL die that does. This could be a custom die ground to fit your chamber, or it could be a “small-base” die specifically designed to “hit” the bottom section of the case. Alex also notes that some FL dies have an inside chamfer at the mouth of the die, right at the very bottom. (See video at 3:55). This can leave the section of the case right above the extractor groove unsized, which can also lead to “clickers” and stiff bolt lift.
Paint Your Brass to Find Problem Areas
If you are having stiff bolt lift or extraction issues, Alex explains that you can “paint” your brass with magic marker (or dye-chem), and then place the case in your chamber. On the “hot spots” where the case contacts the chamber wall, the marking will rub off, allowing the brass metal to shine through in the problem area(s). This will illustrate where you need better sizing from your die.
“You can ink up the case with some magic marker or dye-chem. If you are getting clickers, go ahead and mark up the case and chamber it and see where it’s wearing. This will help you diagnose [whether the problem] is coming from the base, is it coming maybe from a score in the chamber… it can even happen at the shoulder although that’s pretty rare. Usually the dies size enough at that point.”
Did you find this video helpful? View more informative Tech Tip Videos on WheelerAccuracy.com.
Video Tip from Boyd Allen. We welcome reader submissions.
Repeated firings at stout pressures can cause primer pockets to grow in diameter. This can create an unsafe condition if your primers are not seating properly. Are your primer pockets “good to go”, or have they been pushed to the point of no return? Do you really know? Many guys try to gauge primer pocket tightness by “feel”, as they seat the primer. But that method isn’t precise. Now there’s a better way…
The folks at Ballistictools.com have created a handy set of precision-machined gauges that let you quickly and accurately check your primer pockets. These gauges are offered in two sizes — for large and small primer pockets. A two-piece set of both large and small gauges costs just $19.99. These gauges let you quickly measure the depth of a primer pocket, and check if the crimp has been removed properly. Most importantly, the gauge tells you if the primer pocket has opened up too much. One side of the gauge has an enlarged diameter plug. If that “No-Go” side fits in the primer pocket, you should ditch the case — it’s toast.
Precision ground from O-1 tool steel, these primer pocket gauges serve multiple functions. The inventor of these tools explains:
I created the prototype of this tool for my own use in brass processing. I needed a way to quickly and easily measure primer pockets that was reliable and did not require wasting a primer. This tool has been indispensable for me and I would never go back to the old method of uncertainty and guessing.
One side of this gauge is the “go” side which quickly tells you the depth of a primer pocket, whether any crimp is properly removed, and whether the primer pocket is loose. If it feels loose on the “go” side, use the other end of the tool, the “no go” side, to test to see if the primer pocket is too loose to hold a primer. If the no-go slides into the pocket, then you know to junk that brass.
Product tip from Boyd Allen. We welcome reader submissions.
Each Wednesday, the U.S. Army Marksmanship Unit publishes a reloading “how-to” article on the USAMU Facebook page. This week’s “Handloading Hump Day” article covers two basic case prep chores — uniforming primer pockets and deburring flash-holes. Visit the USAMU Facebook page for other tips.
Primer Pocket & Flash-Hole Conditioning
This week, we’ll address a question that frequently arises: “Do you uniform primer pockets and deburr flash-holes?” As we tailor our handloading methods to the specific needs of each instance, the answer, not surprisingly, is “Sometimes!” However, don’t flip that dial just yet, as what determines our approach may be helpful in deciding how to address one’s own techniques. Moreover, we have a buried “Easter Egg” morsel that may bring a chuckle, as well as useful safety information!
Generally, the USAMU Handloading Shop does not uniform primer pockets (PP) or deburr flash holes (FH) of our rifle brass. We’re certainly not against it… Rather, this reflects the very high volume of ammunition we load, the fact that very few cases are ever re-loaded for a second firing, and the types of brass we use. However, as a need is perceived, we DO deburr flash holes. Of interest, we have fired many very small, 1000-yard test groups and aggregates using weight-selected, domestic brass that had not had PPs uniformed or FHs deburred.
Before and After — On the left is a fired, deprimed 7.62×51 case with primer residue intact. On the right the primer pocket has been uniformed to SAAMI specs. Note the shiny finish at the bottom of the pocket — evidence of the the removal of metal when uniforming the primer pocket.
As to the type cases we use, many thousands of our long-range 5.56mm cases come to us from the arsenal with the primer of our choice pre-installed and staked-in, per usual practice. Obviously, we cannot uniform either FHs or PPs on this live, primed brass. However, after careful sorting, inspection and preparation, we do obtain match-winning results with it.
Shooters who reload their brass several times may decide to uniform PPs and deburr FHs, especially on their “300-yard and beyond” brass. Here, they will use the cases many times, while the uniforming is performed only once. Also, most handloaders only process moderate amounts of brass, compared to our multi-thousand round lots.
Having high quality Long Range (LR) brass helps. Many of the better brass manufacturers install their flash holes so that no burrs are created. Still, it does pay to inspect even THESE manufacturer’s products, as occasional slips are inevitable. Very rarely, some of the best makers will have a significant burr in, say, 1 per 1000 or 2000 cases, and it’s worth catching those.
Exceptions can always be found. Recently, we began processing a large lot of match brass from a premier manufacturer. We were startled to find that every case had a significant burr in the FH — something we’d never before seen from this maker. We then broke out the FH deburring tools and went to work.
Some observers have noted that it can be difficult to truly verify the contribution to accuracy of these procedures — particularly when firing from the shoulder, in conditions. Members of this staff, as individual rifle competitors, do often perform these operations on their privately-owned LR rifle brass. One could ascribe this to the old Highpower Rifle maxim that “if you think it helps, then it helps.”
However, a World Champion and Olympic Gold/Silver medalist here commented on his own handloading (for International competition, which demands VERY fine accuracy). He noted that he did seem to see a decline in accuracy whenever he did not uniform FHs, deburr FHs and clean primer pockets before each reloading. (One might be tempted to counter that only a truly World Class shooter could reliably detect the difference.) However, with the wisdom of decades experience, our Champion also remarked that “It could have been that I just wasn’t shooting as well that day.”
For those who do opt for these procedures, note that various tool models may have adjustable depth-stops; pay attention to the instructions. Some FH-deburring tools (which enter the case mouth, not the primer pocket) are dependent upon uniform case length for best results.
Above is a flash-hole deburring tool on an RCBS powered case-prep unit. These case prep machines can save a lot of pain and misery, helping one perform various functions quickly and efficiently.
Can you form a wildcat cartridge such as the 6 Dasher without expending primer, powders, and bullets? Absolutely. Using the hydro-forming method you can form improved cases in your workshop with no firing whatsoever, so there is no wear on your precious barrel. Watch this video to see how it’s done:
6 Dasher Case Hydro-Forming Demonstration:
Forum member Wes J. (aka P1ZombieKiller) has produced a helpful video showing how to form Dasher cases use the Hornady Hydraulic forming die kit. This includes a two-part die (body and piston), and a special shell holder. To form the case, you insert a primer in your virgin brass, top the case off with with a fluid (water or alcohol), then run the case up into the Hydro-forming die. A few stout whacks with a hammer and your case is 95% formed.
Hydro-Forming Procedure Step-by-Step:
1. Insert spent primer in new 6mmBR brass case.
2. Fill with water or alcohol (Wes prefers alcohol).
3. Wipe excess fluid off case.
4. Place case in special Hornady shell-holder (no primer hole).
5. Run case up into Hydraulic forming die.
6. Smack top piston of forming die 3-4 times with rubber mallet or dead-blow hammer.
7. Inspect case, re-fill and repeat if necessary.
8. Drain alcohol (or water) into container.
9. Remove primer (and save for re-use).
10. Blow-dry formed case. Inspect and measure formed case.
Wes achieves very uniform cartridge OALs with this method. He measured ten (10) hydro-formed 6 Dasher cases and got these results: two @ 1.536″; 2 @ 1.537″; and 6 @ 1.538″.
Three or Four Whacks Produces a 95%-Formed Case
With a Hornady hydro-forming die, hydraulic pressure does the job of blowing out the shoulders of your improved case. The process is relatively simple. Place a spent primer in the bottom of a new piece of brass. Fill the case with water, and then slip it into a special Hornady shell-holder with no hole in the middle. Then you run the case up into the forming die. Now comes the fun part. You gently insert a plunger (hydraulic ram) from the top, and give it three or four stiff whacks with a mallet (or better yet, a dead-blow hammer). Remove the plunger and you have a 95% formed case, ready to load.
Hornady supplies a shell holder made specifically for the hydro die; there’s no hole in the bottom of it. Just insert a spent primer into the primer pocket and you’re ready to go. The spent primer combined with the solid shell holder, keeps the water from seeping out of the primer pocket. The primer pushes out a little bit during this process, but it’s impossible for it to come out because of the way the shell holder is designed. The shell holder has a grove which allows the case to slide out of the shell holder even when the primer protrudes a bit.
Story tip from Boyd Allen. We welcome reader submissions.