At SHOT Show 2013 we had the chance to chat with legendary barrel-maker John Kreiger of Krieger Barrels. In this wide-ranging interview, John addressed a number of questions our readers often pose…. What is better for a 6mm, 0.236″ land or 0.237″ land? What are the pros/cons of various barrel types: 3-groove, 4-groove, 6-groove, 8-groove, and 5R? What types of land/groove configurations clean up more easily? (John says the 5R might be the winner there).
John also discusses barrel cleaning and he explains why it’s unwise to pull a dirty brush back across your delicate crown: “The problem comes from the fact that abrasive materials — powder and primer residues in particular — get embedded in the brush. Essentially that is how a lap works.”
When we suggested that Krieger Barrels might want to offer three-groove barrels in the future, John surprised us by revealing that he has been considering putting a 3-groove design into production. John says that, in theory at least, a canted-land 3-groove holds a lot of promise. John hopes to build some prototype 3-grooves to test. Krieger Barrels has a 300-yard underground tunnel where barrels with various land/groove configurations and calibers can be tested using a return-to-battery fixture. John admits that tunnel testing of barrels is “on the back burner” as his company focuses on filling orders. But he says that he has a strong personal interest in testing different land/groove configurations, different amounts of choke, and different internal dimensions. We hope we’ll be able to share some results from the Krieger Barrels test tunnel in the near future.
Barrel-maker Dan Lilja’s website has an excellent FAQ page that contains a wealth of useful information. On the Lilja FAQ Page as you’ll find informed answers to many commonly-asked questions. For example, Dan’s FAQ addresses the question of barrel life. Dan looks at factors that affect barrel longevity, and provides some predictions for barrel life, based on caliber, chambering, and intended use.
Dan cautions that “Predicting barrel life is a complicated, highly variable subject — there is not a simple answer. Signs of accurate barrel life on the wane are increased copper fouling, lengthened throat depth, and decreased accuracy.” Dan also notes that barrels can wear prematurely from heat: “Any fast varmint-type cartridge can burn out a barrel in just a few hundred rounds if those rounds are shot one after another without letting the barrel cool between groups.”
Q. What Barrel Life, in number of rounds fired, can I expect from my new barrel?
A: That is a good question, asked often by our customers. But again there is not a simple answer. In my opinion there are two distinct types of barrel life. Accurate barrel life is probably the type most of us are referencing when we ask the question. But there is also absolute barrel life too. That is the point where a barrel will no longer stabilize a bullet and accuracy is wild. The benchrest shooter and to a lesser extent other target shooters are looking at accurate barrel life only when asking this question. To a benchrest shooter firing in matches where group size is the only measure of precision, accuracy is everything. But to a score shooter firing at a target, or bull, that is larger than the potential group size of the rifle, it is less important. And to the varmint hunter shooting prairie dog-size animals, the difference between a .25 MOA rifle or one that has dropped in accuracy to .5 MOA may not be noticeable in the field.
The big enemy to barrel life is heat. A barrel looses most of its accuracy due to erosion of the throat area of the barrel. Although wear on the crown from cleaning can cause problems too. The throat erosion is accelerated by heat. Any fast varmint-type cartridge can burn out a barrel in just a few hundred rounds if those rounds are shot one after another without letting the barrel cool between groups. A cartridge burning less powder will last longer or increasing the bore size for a given powder volume helps too. For example a .243 Winchester and a .308 Winchester both are based on the same case but the .308 will last longer because it has a larger bore.
And stainless steel barrels will last longer than chrome-moly barrels. This is due to the ability of stainless steel to resist heat erosion better than the chrome-moly steel.
Barrel Life Guidelines by Caliber and Cartridge Type
As a very rough rule of thumb I would say that with cartridges of .222 Remington size you could expect an accurate barrel life of 3000-4000 rounds. And varmint-type accuracy should be quite a bit longer than this.
For medium-size cartridges, such as the .308 Winchester, 7×57 and even the 25-06, 2000-3000 rounds of accurate life is reasonable.
Hot .224 caliber-type cartridges will not do as well, and 1000-2500 rounds is to be expected.
Bigger magnum hunting-type rounds will shoot from 1500-3000 accurate rounds. But the bigger 30-378 Weatherby types won’t do as well, being closer to the 1500-round figure.
These numbers are based on the use of stainless steel barrels. For chrome-moly barrels I would reduce these by roughly 20%.
The .17 and .50 calibers are rules unto themselves and I’m pressed to predict a figure.
The best life can be expected from the 22 long rifle (.22 LR) barrels with 5000-10,000 accurate rounds to be expected. We have in our shop one our drop-in Anschutz barrels that has 200,000 rounds through it and the shooter, a competitive small-bore shooter reported that it had just quit shooting.
Remember that predicting barrel life is a complicated, highly variable subject. You are the best judge of this with your particular barrel. Signs of accurate barrel life on the wane are increased copper fouling, lengthened throat depth, and decreased accuracy.
Benchrest Barrel Life — You May Be Surprised
I thought it might be interesting to point out a few exceptional Aggregates that I’ve fired with 6PPC benchrest rifles with barrels that had thousands of rounds through them. I know benchrest shooters that would never fire barrels with over 1500 shots fired in them in registered benchrest matches.
I fired my smallest 100-yard 5-shot Aggregate ever in 1992 at a registered benchrest match in Lewiston, Idaho. It was a .1558″ aggregate fired in the Heavy Varmint class. And that barrel had about 2100 rounds through it at the time.
Another good aggregate was fired at the 1997 NBRSA Nationals in Phoenix, Arizona during the 200-yard Light Varmint event. I placed second at this yardage with a 6PPC barrel that had over 2700 rounds through it at the time. I retired this barrel after that match because it had started to copper-foul quite a bit. But accuracy was still good.
Take a look at that unusual target below. We bet you’ve never seen one of these before. It’s a 50-Yard Sighting Target for the M1 Garand. It’s designed to allow a rifleman to confirm his zeros for multiple yardages all the way out to 1000 yards. But importantly, he can establish those zeros at a very “short” shooting facility, since the target is positioned at a mere 50 yards.
Here’s how it works. The target is placed at fifty (50) yards. You start at the bottom, aiming at the black circle. Then check your come-up table and work your way up, clicking step-by-step to the various horizontal lines set for 200, 300, 500, 600 and 1000 yards. This is NOT “spray and pray” — you need to have a pretty good idea of the clicks you need, based on your ammo’s ballistics. This target is calibrated for the U.S. Military M72 Ball Ammo. The targets are available from Champion’s Choice ($0.75 each) or from Creedmoor Sports (12 for $5.95).
Lapua’s Kevin Thomas used this target to get zeroed for the recent D-Day Anniversary Match at the Talladega Marksmanship Park. Kevin used the target for both his M1 Garand as well as his M1903A1 Springfield, both chambered for the .30-06 Springfield cartridge.
Zeroing at a Short Distance — How to Use the 50-Yard Sighting Target, by Kevin Thomas
As part of my preparation for the Garand Match at the CMP’s Talladega Marksmanship Park, I needed to zero my new M1 Garand, but I was crunched for time. I didn’t have time to get to my normal range and confirm zeros at actual yardages. But a 50-yard zero target came to the rescue. Made for M1s using the M72 National Match ammo, the target allows the shooter to establish fairly good zeros at 200, 300, 500, 600 and 1,000 yards if you’ve got access to a 50-yard range.
I have no idea when these 50-yard Sighting Targets were first developed, but they’ve been around for at least as long as I’ve been involved in this game (longer than I care to admit). It consists of a tall target, with a smallish black bullseye located at the bottom center. The bullseye is an aiming point only. Extending through the top of the target is a vertical line that runs directly up the center, to nearly the top of the paper. Across this, there are intersecting horizontal lines that are marked 200, 300, 500, 600 and 1,000.
The target was designed for the M1 rifle using then-issued M72 National Match ammunition. This ammo launched a 173gr FMJBT bullet at approximately 2,640 fps. It was a good load in its day, supersonic out to the 1,000-yard line. While that ammo is fairly scarce these days, this isn’t a problem for the handloader. My standard match load for the M1 Garand utilizes the 175gr Lapua Scenar HPBT, and delivers remarkably similar ballistic performance. Thus my normal Garand load translates nicely to this 50-yard target. Yes, this is by design. No point in reinventing the wheel when Lake City has already established what works!
In use, the shooter sets the target up at a measured 50 yards, and (this is critical) checks the vertical line with a plumb bob or a carpenter’s level, to ensure that it is absolutely vertical. Once the target is set, the rifle is fired and the group noted. From there, it is a simple matter of zeroing it normally to bring the groups into alignment with the vertical line, at the elevation needed for a particular range. Once your group is hammering the intersection of the vertical line and the horizontal line marked “200”, you have established your 200-yard zero for that rifle. Record the number of clicks, and you’re good to go. Raise the impacts up to coincide with the line marked “300” and you now have a 300-yard zero as well. And so on, right up the target. Record those settings in your data book, and you’re ready to go to the range at the full distances. If done carefully, you may be in the X-Ring, but at the very least, you’ll be well-centered and ready to get some hard dope recorded for future shoots.
The same target can also be used with an M14/M1A, at least at the shorter distances. The ballistics of the M118 and the current M118LR are similar enough that this will get you on target at the full distances, probably requiring just a half MOA or so change from the 50 yard zero you recorded. Same bullets, moving at a slightly more sedate 2,550 fps, you’ll be in the ballpark at least.
Bryan Litz has recently popularized the short-range zeroing methods once again, reintroducing it to a new generation of shooters that may not have been aware of the old M72 short-range zero target. The same principles apply, and with the advent of the myriad computer ballistics programs and chronographs on the market today, any shooter can rapidly develop his own zero targets to accomplish the same result. But in the meantime, especially with the M1’s resurgent popularity, it’s nice to know that there’s an easy way to do things without a trip to a full-length range. The modestly-priced 50-Yard Sighting Targets can be ordered through Champion’s Choice or Creedmoor Sports.
Oh, and when I arrived in Talladega, yes, my zeros were good! All’s well that ends well. Safe Shooting! — Kevin Thomas
We often receive questions from varmint hunters and AR shooters regarding barrel length. They want to know how much velocity they will loose if they run a shorter barrel in their .223-Rem rifle. Our friends at Rifleshooter.com did a test that provides some surprising answers to that question.
With barrels, one always wonders “Can a little more length provide a meaningful velocity gain?” To help answer that question, Rifleshooter.com performed an interesting test, cutting the barrel of a .223 Rem rifle from 26″ all the way down to 16.5″. The cuts were made in one-inch intervals with a rotary saw. At each cut length, velocity was measured with a Magnetospeed chronograph. To make the test even more interesting, four different types of .223 Rem/5.56 ammo were chron’d at each barrel length.
Test Barrel Lost 25.34 FPS Per Inch (.223 Rem Chambering)
How much velocity do you think was lost, on average, for each 1″ reduction in barrel length? The answer may surprise you. The average speed loss of the four types of .223/5.56 ammo, with a 9.5″ shortening of barrel length, was 240.75 fps total (from start to finish). That works out to an average loss of 25.34 fps per inch. (See inch-by-inch data HERE.)
5.56/.223 Barrel Cut-Down Speed Test 26″ to 16.5″
Start FPS at 26″
End FPS at 16.5″
Total Loss
Average Loss Per Inch
UMC .223 55gr
3182*
2968
214
22.5 FPS
Federal M193 55gr
3431
3187
244
25.7 FPS
Win m855 62gr
3280
2992
288
30.3 FPS
Blk Hills .223 68gr
2849
2632
217
22.8 FPS
*There may have been an error. The 25″ velocity was higher at 3221 fps.
Rifleshooter.com observed: “Cutting the barrel from 26″ to 16.5″ resulted in a velocity reduction of 214 ft/sec with the UMC 223 55-grain cartridge, 244 ft/sec with the Federal M-193 cartridge, 288 ft/sec with the Winchester M855 cartridge and 217 ft/sec with the Back Hills 223 68-grain match cartridge.”
How the Test Was Done
The testers described their procedure as follows: “Ballistic data was gathered using a Magnetospeed barrel-mounted ballistic chronograph. At each barrel length, the rifle was fired from a front rest with rear bags, with five rounds of each type of ammunition. Average velocity and standard deviation were logged for each round. Once data was gathered for each cartridge at a given barrel length, the rifle was cleared and the bolt was removed. The barrel was cut off using a cold saw. The test protocol was repeated for the next length. Temperature was 45.7° F.”
Much Different Results with 6mmBR and a Longer Barrel
The results from Rifleshooter.com’s .223/5.56 test are quite different than the results we recorded some years ago with a barrel chambered for the 6mmBR cartridge. When we cut our 6mmBR barrel down from 33″ to 28″ we only lost about 8 FPS per inch. Obviously this is a different cartridge type, but also our 6mmBR barrel end length was longer than Rifleshooter.com’s .223 Rem start length. Velocity loss may be more extreme with shorter barrel lengths.
Here’s a helpful hint for hand-loaders from Sierra Bullets. While this article focuses on Sierra’s new Tipped Match-King bullets, the recommended solutions apply to other bullet types as well. The article explains how 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. Here Sierra technician Rich Machholz diagnoses the problem and provides a solution.
Solutions for Ring Marks Caused by Seating Stems
by Sierra Bullets Ballistic Technician Rich Machholz
Now that the new Tipped MatchKing® (TMK) bullets are being shipped and shooters are putting them to use I have received several calls regarding marking on the bullet ogive from the seating stem.
The cause can be traced to one of several things.
In the .223 and especially with the long, 77 grain TMK seated at 2.250” or even 2.260” most loads of Varget® and Reloder® 15 are compressed loads, sometimes heavily compressed. This puts a great deal of pressure on the bullet through the seating stem. The result of all this pressure is a mark of varying depth and appearance on the ogive of the bullet. [Editor: We have seen this issue with a variety of other bullet types/shapes as well, including non-tipped VLDs. The solution is profiling the internal cone of the seating stem to match your bullet shape.]
Some older seating stems might even bear against the tip of the bullet which can make a slight bulge in the jacket just below the junction of the resin tip and the copper jacket in a compressed load. If this is the case there is not a ready fix other than calling the die manufacturer and requesting a new deeper seating stem.
Polish Your Seating Stem to Remove Sharp Internal Edges
If the seating stem is of proper depth the culprit most generally is a thin sharp edge on the inside taper of the seating stem. This is an easy fix that can be accomplished by chucking a spare 77 grain bullet in your drill, coating it with valve grinding compound or even rubbing compound or in a pinch even tooth paste.* Remove the seating stem assembly from the seating die. Turn the drill on and put the seating stem recess over the spinning bullet with the polishing compound to break or smooth the sharp edge that is making the offending mark. This might take more than one application to get the proper polish depending upon what you use, but the more you polish the better the blend of angles which will [ensure the stem matches the bullet contours, not leaving a sharp ring].
If the above is a little more than you care to tackle you might try very fine emery cloth twisted to a point that can be inserted into the mouth to the seating stem and rotated to polish the inside to eliminate any sharp edges that might be present.
Load Advice for 77gr TMKs in the .223 Rem
And last but certainly not least. Actually, even though we don’t say you need additional data for the TMKs, remember you are dealing with heavily-compressed loads in some cases because of the additional bullet length. Due to the additional length of these new bullets and in the interest of gaining some room in the case you might consider trying a slightly faster extruded powder like BenchMark or the 4895s or an even more dense powder like the spherical H335®, CFE223 or TAC. The extra room will allow for trouble free bullet seating also.
Good luck and remember we are no further away than your telephone: 1-800-223-8799.
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 to ensure that Sierra projectiles perform as promised, with repeatable accuracy. Sierra’s 300-meter test range is the longest, privately-owned underground bullet test facility in the world. Sierra offers free tours of the test tunnel as part of Sierra’s Factory Tour Program.
Sierra Bullets tests every new bullet design and each lot of bullets. Sierra tells us: “When [we] change to a new bullet they are continually shooting them until they get the bullet properly set up and running and the range releases them to run (meaning the bullets shoot to spec). [Testers] are required to shoot at any lot change and periodically throughout the lot … even if it is just a press operator change. Lot sizes can vary from 5,000 to over 100,000 thousand. If anything changes — it is a new lot. When a new operator comes on — it is a new lot.”
Bevy of Barreled Actions for Bullet Testing
Sierra Bullets uses dozens of barreled actions for testing bullets. These barreled actions are clamped in stout, return-to-battery test fixtures. These heavy test fixtures provide near-perfect repeatability (with no human-induced holding or aiming errors). Each barrel has its own logbook to track the barrel’s usage. Interestingly, Sierra does not have a specific round count for barrel life. When a barrel starts “opening up”, i.e. showing a decline in accuracy, then the barrel is replaced, whether it has 800 rounds through it or 5,000.
Click Photo to Zoom
Sierra Bullets 10-Shot Groups at 200 yards
What kind of 200-yard accuracy can you get in an enclosed, underground test range? Would you believe 0.162 MOA at 200 yards with a .338? Check out these 10-shot test groups shot at the Sierra Test Range at 200 yards. Note that the numbers listed on each sample are actual measurements in inches. To convert to MOA, cut those numbers in half (to be more precise, divide by 2.094, which is 1 MOA at 200 yards). For example, the 0.340″ middle group works out to 0.162 MOA at 200 yards.
The last half-inch or so of your barrel is absolutely critical. Any damage (or abnormal wear) near the crown will cause a significant drop-off in accuracy. Here are ways you can check the end of your barrel, using a common Q-Tip.
Use Q-Tip for Barrel Inspection To find out if you have a burr or damage to your crown, you can use an ordinary Q-tip cotton swab. Check the edges of the crown by pulling the Q-tip gently out past the edge of the crown. If you have a burr, it will “grab” the cotton and leave strands behind.
Larry Willis has another way to use a Q-Tip: “Here’s a neat trick that will surprise you with how well it works.” Just insert a Q-Tip into your barrel (like the picture below), and it will reflect enough light so that you can get a real good look at the last half inch of rifling and the crown of your barrel. In most cases you’ll find that this works much better than a flashlight. Larry tells us: “I’ve used this method about a jillion times. Q-Tips are handy to keep in your cleaning supplies anyway. This is a good way to judge approximately how well you are cleaning your barrel when you’re at the range. It’s also the best way to examine your barrel when you’re in the field.”
Readers who have just recently discovered the Daily Bulletin may not realize that AccurateShooter.com has hundreds of reference articles in our archives. These authoritative articles are divided into mutiple categories, so you can easily view stories by topic (such as competition, tactical, rimfire, optics, shooting skills etc.). One of the most popular categories is our Technical Articles Collection. On a handy index page (with thumbnails for every story), you’ll find over 100 articles covering technical and gunsmithing topics. These articles can help you with major projects (such as stock painting), and they can also help you build more accurate ammo. Here are five popular selections from our Technical Articles archive.
Complete Precision Case Prep. Jake Gottfredson covers the complete case prep process, including brass weight sorting, case trimming, primer pocket uniforming, neck-sizing, and, case-neck turning.
Stress-Free Pillar Bedding. Richard Franklin explains how to do a top-quality bedding job, start to finish.
OnTarget Software Review. Our Editors test free software that measures shot groups with great precision. We explain how to use the program and configure advanced features.
Savage Action Tuning. Top F-TR shooter Stan Pate explains how to enhance the performance of your Savage rifle by optimizing the torque settings of the action screws.
Stock Painting Instructions. Step-by-step guide for stock painting by expert Mike Ricklefs. Mike shows both simple coverage and fancy effects.
This is a grim tale. A man almost lost the use of his right hand, and did suffer terrible injuries to his fingers. All because he picked the wrong bottle of powder off the shelf.
Similar Labels, Disasterous Consequences
The shooter, Denny K., was assembling some rounds for his brand new 7mm-08 Savage hunting rifle. He thought he was loading with Hodgdon Varget. Instead he had filled his powder measure with Hodgdon TiteGroup, a fast-burning pistol powder. The labels are similar, so the mistake is understandable. But the results were devastating. Here’s what 41 grains of TiteGroup can do in a 7mm-08:
Posting on the Firing Line, in a thread entitled “Lucky to Be Alive”, Denny writes:
“This is the hardest post to post. I know if I had read it a week ago my comment would have been: ‘You have no business reloading’. I had everything perfect, except pouring the wrong powder in the powder measure. I type this slowly with my left hand, embarrassed but … possibly saving someone else a tragedy or, like me, a long drive to the Emergency Room and surgery to save my finger.”
The Still-Sealed Bottle of Varget
Denny did not initially comprehend exactly why the kaboom happened. He thought maybe his new Savage rifle was at fault. Then, on his return home, he discovered something…
Denny wrote: “The seven-hour period it took to go to ER, transport to Trauma Center and surgery made me think it was a Savage rifle issue. Brand new rifle, new brass, triple-checked loading data. The next day I was humbled when I realized the Varget powder was still sealed.
I knew what powder to use. I thought [Varget] was what I used. Not until the following day did I realize the Varget was still sealed.”
At that point, Denny realized what caused the accident — “operator error”. He knew he had to warn others about using the wrong powder: “I knew I needed to share my mistake, even though it is embarrassing, just to remind people. I’ve been reloading for 30 years…”
Editor’s Comment: Denny was not a novice reloader. His experience demonstrates that this kind of mistake can be made by any hand-loader, even one with decades of experience. Be safe guys, take your time when you load your ammo. Remove powders from measures after your loading sessions (pistol powders can look very similar to rifle powders). And by all means CHECK the LABEL on the jug. As the TiteGroup label says: “A little goes a long way.”
It’s not a bad idea to separate your pistol powders from your rifle powders, or perhaps even load for pistol in a separate part of your workshop.
In our Shooters’ Forum, a member recently noted that he needed to pull down (disassemble) some ammunition that was loaded incorrectly by one of his shooting buddies. You can use an impact puller to do this task, but if you have more than a dozen rounds or so, you may prefer to use a collet-style bullet puller. These work very quickly and positively, making quick work of big jobs. The efficiency of the collet-style puller is worth the investment if you frequently disassemble ammo. These devices retail for under $25.00 (collets sold separately). Normally, you’ll need a specific collet for each bullet diameter. But collets are not that costly, so this isn’t a big deal, particularly if you only load a few calibers, such as .223, 6mm, and .308.
Hornady and RCBS use different mechanisms to tighten the collet around the bullet. On Hornady’s Cam-Lock Bullet Puller, a lever-arm on the top of the bullet puller serves to tighten the collet around the bullet. Simply rotate the lever from the vertical to the horizontal position to grab the bullet. Lower the ram to remove the case. The bullet will drop out when you return the lever arm to the vertical position. This is demonstrated in the video below:
Hornady Cam-Lock Bullet Puller Demonstrated
Collet bullet-pullers resemble a loading die with a lever or handle on the top. They screw into a standard reloading press. Hornady and RCBS both make collet-style bullet pullers. They use the same basic principle — the device tightens a collet around the bullet, and then the bullet is separated from the case by lowering the press ram. NOTE: Collet pullers may leave small marks on your bullets, unlike impact (kinetic) pullers.*
Like the Hornady tool, the RCBS Bullet Puller employs a collet to grab the bullet. However, the RCBS tool tightens the collet in a different way. The head of the RCBS tool is threaded internally. By rotating the lever arm clockwise in a horizontal circle you squeeze the collet around the bullet. To remove the bullet, after lowering the press ram, simply spin the lever arm back in the opposite direction. The use of the RCBS tool is demonstrated in this video:
RCBS Collet Bullet Puller Demonstrated:
WARNING: When removing bullets from loaded cartridges, always make sure there are no obsructions or debris in your shell-holder or under the loaded round. NEVER engage a primer seating accessory on your press when working with loaded rounds. You can cause a round to discharge by contacting the primer! Also, we recommend you keep your head and torso away from the bullet puller tool at all times.
*By contrast, impact pullers rarely mark bullets, particularly if you put a little bit of foam or paper wadding in the closed end of your impact puller. When dismantling loaded rounds, powder kernels can get trapped in the wadding, so you should remove and replace the wadding before changing to cartridges loaded with a different powder type (assuming you intend to save the powder).
At SHOT Show 2013 we had the chance to chat with legendary barrel-maker John Kreiger of Krieger Barrels. In this wide-ranging interview, John addressed a number of questions our readers often pose…. What is better for a 6mm, 0.236″ land or 0.237″ land? What are the pros/cons of various barrel types: 3-groove, 4-groove, 6-groove, 8-groove, and 5R? What types of land/groove configurations clean up more easily? (John says the 5R might be the winner there).
To find out if you have a burr or damage to your crown, you can use an ordinary Q-tip cotton swab. Check the edges of the crown by pulling the Q-tip gently out past the edge of the crown. If you have a burr, it will “grab” the cotton and leave strands behind.
Like the Hornady tool, the 
