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November 1st, 2017
This article was written in 2014 for the Sierra Bullets Blog. It describes one method of load development that is commonly used. There are other methods that can work also. Some guys first isolate seating depth and then fine-tune velocity with charge weights. Other guys may aim for a known velocity node (speed range) and then optimize accuracy by adjusting seating depth. Still others look for smallest ES and tightest vertical to minimize 1000-yard vertical dispersion. There are many ways to skin a cat. Different rifles (and even different barrels) can demand different styles of load development.
In this instance the writer achieved desired results seating his bullets .007″ back from max “jam” length. For other applications (and other barrels) you may get the best, most consistent results seating off the rifling by .020″ or more. In disciplines with quick-fire such as PRS, it may be wise to develop loads that “jump” the bullet.
F-Class Long Range Load Development Methodology
by Mark Walker, Sierra Bullets Product Development Manager
Since I just put a new barrel on my F-class rifle… I figured it might be a good time to discuss load tuning for long range shooting. Getting the most accuracy out of your rifle is one of the most important aspects of load tuning. For long range shooting in particular, using a load that produces the least amount of vertical variation is vital. There are several steps to the process that I use, so I will go through the basics of each.
When I first get a new barrel installed, I like to determine what the loaded cartridge “jam” length is. I do this by taking an empty case (no powder or primer) that has been neck sized with the proper bushing (I like to shoot for 0.002 smaller than the loaded cartridge neck diameter) and seat a bullet long in it so that the throat of the rifle will move the bullet back into the case when I close the bolt. I close the bolt several times until the bullet stops moving back into the case at which point I use a comparator with my calipers and get a length measurement on the cartridge. This is what I consider to be the “jam length” for this barrel and chamber. I came up with 3.477″ as the “jam length” for this particular barrel. [Editor: In this instance, Mark is using “Jam length” to mean max seating depth he can achieve without bullet set-back.]
Next, I will fire-form some brass using a starting load of powder and bullets seated to “jam” while breaking in the barrel. My barrel break in process is not very technical; it’s mostly just to get the brass formed and the rifle sighted in. I do clean every 5 rounds or so just because I feel like I have to.
Once I have the brass formed, I use them to load for a “ladder test” to see what powder charge the rifle likes. With a ladder test, you take your starting load and load one round each with a slightly increasing amount of powder until you reach your max load for that cartridge. You then fire each round using the same aiming point to see where the bullets start to form a group. For this barrel and cartridge, I started at 53.3 grains of H4831SC powder and increased the load by 0.3 grains until I reached 55.7 grains. I always seat my bullets to “jam” when doing a ladder test. We will determine the final seating depth in another test later. It’s usually best to shoot this test at a minimum of 200 yards because at closer ranges the bullets will impact too close together making it hard to determine which load works best. I shot this test at 300 yards.
As you can see from the target, the lightest load #1 had the lowest velocity and impacted lowest on the target. Shots #2 and #3 were a little higher and in the same hole. Shots #4 thru #6 were slightly higher yet and all had the same elevation. Shots #7 and #8 were the highest on the target however pressure signs were starting to show. For some reason shot #9 went back into the group and the chronograph didn’t get a reading so I ignored that shot.
When picking a load, I am looking for the most shots at the same vertical location on the target. As you can see that would be shots #4 through #6 so I would pick a powder charge from those shots which would be 54.2 grains to 54.8 grains. As a side note, shots #2 and #3 are only 0.851 lower so I wouldn’t be afraid of using one of those loads either. I settled on 54.5 grains as the load I wanted to use. It’s right in the middle of the group so if the velocity goes up or down slightly, the bullet should still hit in the same place on the target.
Now that we’ve settled on a powder charge, I want to find the seating depth the rifle likes. I usually start at jam length and [shorten the COAL] in 0.003 increments until I get to 0.015 deeper than jam. [Editor: By this he means he is seating the BULLET deeper in the case, NOT deeper into the lands. He ended up at .007″ shorter than his hard jam length of 3.477″.]
I load 3 rounds at each depth using the 54.5 grain powder charge and shoot a group with each depth at 150 yards. As you can see from the target, the first two groups are not good at all. Next one looks good and is the smallest group on the target. The next three are not quite as small but the vertical location on the target is almost the same which indicates a sweet spot which will help keep the vertical stringing to a minimum on target. I went with 3.470″ which is right in the middle once again and should give some flexibility with the seating depth.
So after all of that, my load is 54.5 grains of H4831SC and a cartridge length of 3.470. I plan on loading up enough ammo to shoot five groups of five shots and see exactly how this load works on target as well as what the extreme velocity spreads are over several groups.
I sincerely hope some of this information helps you to get the best accuracy out of your rifle. I do not take credit for coming up with any of this, a whole lot of good shooters use this same method or a variant of it when working up their loads.
For more information about load development, please contact the Sierra Bullets technical support team at 1-800-223-8799 or by email at sierra [at] sierrabullets.com.
Disclaimer: Load data represented here may not be safe in your rifle. Always start low and work up, watching for pressure signs.
October 13th, 2017
Up until now, 147 grains was the high end of 6.5 mm (.264 diameter) match bullets offered by major bullet-makers. Now Sierra has “raised the bar” — releasing a 150-grainer with a killer 0.713 G1 Ballistic Coefficent (BC). You read that right — 0.713! Compare that to the 0.626 G1 BC for Sierra’s well-known 142gr MatchKing, 0.697 for the Hornady 147gr ELD Match, and 0.607 for the Berger 140gr Hybrid Target. To increase (and uniform) the BC, Sierra’s new 150-grainer is pointed at the factory. Recommended barrel twist rate is 1:7.5″.
CLICK HERE for 6.5 Creedmoor LOAD DATA for this new 150gr Matchking.
Sierras’ product announcement states: “Shooters … will appreciate the accuracy and extreme long range performance of our new 6.5 mm 150 grain HPBT (#1755). A sleek 27-caliber elongated ogive and a final meplat reducing operation (pointing) provide an increased ballistic coefficient for [reduced wind drift] and velocity retention. To ensure precise bullet-to-bore alignment, a unique bearing surface-to-ogive junction uses the same 1.5-degree angle commonly found in many match rifle chamber throats. This bullet requires a twist rate of 1:7.5″ or faster to stabilize.”
Sierra’s new 6.5 mm 150 grain HPBT MatchKing bullet is available in 100-count boxes (#1755) for $50.98 MSRP, and 500-count boxes (#1755C) for $226.45 MSRP.
August 23rd, 2017
Here is the original Sierra manufacturing facility in Whittier, CA.
On August 22, 2017 it was announced that Sierra Bullets has been sold to Clarus Corporation (NASDAQ: CLAR), a Utah-based holding company that also owns Black Diamond Equipment Ltd., makers of ski and mountain gear/apparel. Given the importance of this acquisition, we thought our readers might want to learn more about Sierra’s history, and how it makes its bullets…
Sierra Bullets — How It Got Started
Report Based on Story by Carroll Pilant, Sierra Bullets Media Relations Manager
What became Sierra Bullets started in the late 1940s in a Quonset hut in California. In 1947, three aircraft machinists, Frank Snow, Jim Spivey, and Loren Harbor, rented machine space to produce rivets for the aircraft industry along with fishing rod guides and rifle front sight ramps. In the post-WWII years, sport shooting was becoming hugely popular, but quality ammunition was in short supply. For shooting enthusiasts, reloading was the solution to the ammo supply shortage. Snow, Spivey, and Harbor recognized this, creating Sierra Bullets to help fill the void. Before long, they were selling a 53-grain match bullet to the Hollywood Gun Shop. These bullets are still in production today as the Sierra #1400 53-grain MatchKing.
A few years later, an accomplished competitive shooter named Martin Hull joined Sierra. Hull helped develop new bullet types and served as manager of Sierra’s ballistics laboratory for nearly 20 years. With Hull’s help, Sierra’s output grew rapidly. The California company outgrew several locations before it moved to a large facility in Santa Fe Springs, CA, in 1963.
New Owners and New President in the Late Sixties
In 1968, the Leisure Group bought Sierra Bullets. Other Leisure Group companies included Lyman Reloading, High Standard Manufacturing Company, Yard Man, Thompson Sprinkler Systems, Flexible Flyer Sleds, and Dodge Trophies (Which made the Oscar and Rose Bowl Game trophies).
Soon after purchasing Sierra, the Leisure Group hired Robert Hayden as President and General Manager. Hayden was a mechanical engineer who had worked for Remington Arms. Hayden remained the president of Sierra for 42 years, retiring in 2012 when Pat Daly became president.
Sierra Moves to Missouri
In 1990, Sierra relocated to Sedalia, Missouri, where the company remains today. Sierra Bullets now employs over 100 people including five full-time ballistic technicians who answer daily reloading and firearms questions by both phone and e-mail.
The Making of MatchKings — How Sierra Produces SMKs
All Sierra bullets begin life as a strip of gilding metal, an alloy consisting of 95% copper and 5% zinc. To meet Sierra’s strict quality requirements, the gilding metal requires three times more dimensional and quality control standards than is considered standard in the copper manufacturing industry.
A blanking press stamps out a uniform disc and forms the cup that will be drawn into the MatchKing jacket. The cup is then polished and sent to a draw press to be drawn into a jacket that is longer than needed for the future MatchKing, thus allowing for the trim process. Press operators constantly check concentricity to make sure we have only quality jackets. The jackets then go to a trimmer where they are visually inspected again.
After being polished a second time, the jacket travels to the bullet press. In the meantime, 80-pound lead billets are being extruded into lead wire for the cores where great care is taken so that the core wire is not stretched. The core wire is lightly oiled before continuing to the bullet press to be swaged.
The lead core wire and trimmed jacket meet at the bullet press where the first stage forms a boattail on the jacket. The lead core is then formed on top of the bullet press and fed down into the jacket. In one stroke of the press, the MatchKing is formed.
Quality control technicians pull samples from each lot of MatchKings to make sure they meet Sierra’s stringent standards. Samples are then sent to Sierra’s 300-meter underground test range (shown below) to be shot for accuracy on mechanical mounts referred to as “unrestricted return to battery rests” that Sierra designed and built in-house.
After inspection, the bullets are placed in the familiar green box along with reloading labels. They are then shrink-wrapped and shipped all over the world.
August 22nd, 2017
Sierra Bullets has been acquired by Clarus Corporation (NASDAQ: CLAR) for the sum of $79,000,000, “subject to a post-closing working capital adjustment”. Sierra is one of the world’s leading producers of bullets for hunters, sportsmen, and target shooters. With revenues topping $30,000,000 per year, Sierra has long been a major force in the firearms world. Clarus, formerly Black Diamond Inc., is a Utah-based holding company which “seeks opportunities to acquire and grow businesses that can generate attractive shareholder returns”. Clarus also owns Black Diamond Equipment, Ltd., maker of outdoor equipment/clothing for the climbing, skiing and mountain sports markets.
StreetInsider.com reports: “The transaction is expected to be immediately accretive to Clarus’ earnings per share. For the unaudited 12 months ended June 30, 2017, Sierra’s total revenues were approximately $32 million with EBITDA of approximately $12.5 million, representing a purchase price multiple of approximately 6.3x EBITDA. Sierra has a strong cash flow profile, generating free cash flow conversion of approximately 95% with limited ongoing capex requirements.”
“The team at Sierra has continued building on a 70-year legacy dedicated to the highest-level of precision in design, world-class manufacturing and quality control,” said Warren B. Kanders, executive chairman of Clarus. “These attributes have cultivated a diverse customer base of enthusiasts and industry OEMs that drive high recurring revenue and strong cash flow, which we expect to maximize through the utilization of our net operating loss carry forwards.”
Sierra’s President Pat Daly commented: “Our team takes great pride in developing and manufacturing the most precise and accurate bullets in the world. This is supported by our deep institutional knowledge of highly-specialized manufacturing processes that have produced leading products and created a significant competitive advantage. As the only pure-play bullet brand, it was important for us to partner with a team that shares our values and commitment to excellence, and we are excited to join the Clarus family. I look forward to staying on to continue driving our brand growth.” All senior management are expected to remain with Sierra under Clarus’ ownership.
About Sierra Bullets
Founded in 1947 in California, Sierra Bullets is an American manufacturer of bullets. Based in Sedalia, Missouri since 1990, Sierra manufactures a wide range of bullets for both rifles and pistols. Sierra’s product line, recognized by iconic “green box” packaging, includes popular brands such as MatchKing, GameKing, and BlitzKing. Sierra bullets are used for precision target shooting, hunting, and defense purposes. For more information, visit SierraBullets.com.
News Tip from Boyd Allen. We welcome reader submissions.
August 14th, 2017
At the request of our readers, we provide select “Deals of the Week”. Every 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.
1. Bullets.com — Huge Reloading Powder Sale — Great Prices
Got powder? If you need smokeless propellants for your rifles and pistols, head over to Bullets.com which has slashed prices on its powder inventory. There are great savings to be had here, honest. We compared Bullets.com’s inventory reduction sale pricing with some other online powder vendors. With Bullets.com’s current price cuts, you can SAVE $4-$7 per pound for even high-demand powders such as Varget. Bullets.com’s powder sale is scheduled to run through 8/23/2017; however, prices are subject to change. Here are examples of current Sale Prices.
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Hodgdon CFE Pistol, $17.99/lb
Hodgdon Varget, $21.99/lb
Alliant Reloder 17, $22.95/lb
IMR 4064, $22.95/lb
Hodgdon H1000, $22.99/lb |
Hodgdon CF3 223, $149.99/8 lbs.
IMR 8208 XBR, $159.99/8 lbs.
Hodgdon H4198, $169.95/8 lbs.
Hodgdon H4831sc, $175.00/8 lbs.
Accurate LT-32, $189.95/8 lbs. |
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2. CDNN — Winchester XPR Hunting Rifle, $279.99 After Rebate
Looking for a good hunting rifle at a great price? Check out this promotion for the Winchester XPR. This is a fine-handling rig with a smooth bolt and many chambering options. Right now at CDNN Sports the basic gray-stocked Winchester XPR is on sale for $379.99. But here’s the kicker, Winchester is offering a $100.00 Mail-In Rebate. That drops your net cost to just $279.99. That’s an insanely good deal. You can also get the XPR in Vias Camo for $299.99 after rebate.
3. Stocky’s — LR Stocks with Aluminum Bedding Block, $179.99
Here’s a good deal on a versatile Stocky’s Long Range Stock with aluminum V-block bedding system. For just $179.99, order this for Rem/Rem Clone long actions or short actions, with either narrow or wide (varmint/tactical) barrel channel. This would be a good choice for a varmint rifle. This is also offered with handsome hydrographic or web-pattern baked-on textured finishes for $199.99.
4. Amazon — Frankford Complete Master Tumbler Kit, $48.05
This Master Tumbler Kit contains everything you need to tumble rifle or pistol brass. Now on sale for $48.05 with free Prime shipping, this Kit contains: Vibratory Tumbler, Rotary Media Separator, Plastic Bucket, 3 lbs. Cleaning Media, and 4 oz. Brass Polish. NOTE: We considered this an excellent deal when it was priced around seventy bucks. At $48.05 it is a total steal — you could easily pay more than that for a decent vibratory tumbler alone.
5. Champions Choice — Deluxe 58″-Long Rifle Case, $68.00
Many of our readers shoot Palma, F-Class, and ELR rifles with long barrels (up to 35″). It’s difficult to find high-quality, well-padded cases that fit very long rifles. Champion’s Choice offers just such a product, the 58″ Deluxe Soft Rifle Case. With thick 1″ padding on each side, big pockets, and backpack straps, this black/blue/white gun case has earned rave reviews from our Forum members. There’s plenty of room for big scopes, and it even comes with an internal tube to hold your cleaning rod.
6. Natchez — Leupold VX-6 Scopes Closeout, Save Hundreds
Natchez Shooters Supplies is running a big sale on Leupold VX-6 scopes. You can save hundreds of dollars on a wide variety of VX-6 optics, from 1-6x24mm up to 3-18x50mm models. If you are looking for a high-quality hunting optic at a great price check out these deals. For example, Leupold’s 2-12x42mm FireDot (Illum.) Duplex VX-6 scope is marked down from $1199.99 to just $749.99 — a $450.00 savings! Shown above are four hot deals, but a dozen Leupold VX-6 models on are sale now.
7. Precision Reloading — Sierra Bullets Sale, Big Discounts
Now through 8/25/2017 Precision Reloading is running a BIG SALE on Sierra bullets. These projectiles, including MatchKing (MK) and Tipped Match-King, are being offered at deep discounts. Listed below are some of the many types of Sierra Bullets on sale. In many cases you can choose either 100-ct or 500-ct packages. Along with match projectiles, Sierra hunting and varmint bullets are on sale.
Sierra 30 Cal, 195gr Tipped MK, 100 for $41.39 (marked down from $45.99)
Sierra 30 Cal, 155gr HPBT MK, 100 for $34.64 (marked down from $38.49)
Sierra 7mm, 183gr HPBT MK, 100 for $41.84 (marked down from $46.49) (Great new bullet)
Sierra 6.5mm, 142gr HPBT MK, 100 for $36.44 (marked down from $40.49)
Sierra 6.5mm, 123gr HPBT MK, 100 for $35.09 (marked down from $38.99)
Sierra 6mm, 107gr HPBT MK, 100 for $28.34 (marked down from $31.49)
Sierra 6mm, 95gr Tipped MK, 100 for $30.59 (marked down from $33.99)
Sierra 22 Cal, 80gr HPBT MK, 50 for $15.29 (marked down from $16.99)
Sierra 22 Cal 77gr Tipped MK, 100 for $27.44 (marked down from $30.49)
8. Midsouth — CCI Std Velocity .22 LR Ammo, $3.75 for 50ct Box
Here’s a great low-price on quality, CCI .22 LR rimfire ammo. The sale price of $3.75 per 50-ct box works out to just 7.5 cents a round for this 40gr CCI 1070 fps rimfire ammo. At that price you can enjoy rimfire plinking without worrying about cost — just like the “good old days”.
9. Amazon — Discovery Scope Level, $13-$16 (1″, 30mm)
If you shoot long range, you need a scope level. This Discovery scope level is fully CNC-machined to close tolerances for a good fit. It is available with inner diameters to fit scopes with either 1″ or 30mm main tubes. The 1″ version is just $12.99 while the 30mm model is $13.95. You could easily pay $35.00 or more for a 30mm scope level. Purchasers have praised this product: 89% of verified buyers rated this five stars.
August 10th, 2017
Game image courtesy OutdoorNebraska.gov/deer.
Written by Sierra Bullets Ballistic Technician Paul Box
Judging by the calls I’ve had through the years, I think some shooters might be placing too much importance on Ballistic Coefficient (B.C.). The best example of this comes from a call I had one day. This shooter called wanting the ballistic coefficient of one of our Sierra bullets. After I told him he seemed a little disappointed, so I ask him what his application was. Long range target, deer hunting in the woods? Talk to me.
As it turned out, he hunted deer in open timber. He very rarely shot beyond 100 yards. I pointed out to him that, under 200 yards, B.C. has little impact. Let’s compare a couple of bullets.
Let’s look at the trajectory of a couple of bullets and see how they compare. The .30 caliber 180 grain Round Nose #2170 RN and the 180 grain Spitzer Boat Tail #2160 SBT. The round nose has a B.C. of .240, while the SBT is .501. Starting both bullets out of the muzzle at 2700 FPS [with a 100-yard ZERO], at 200 yards the #2170 RN impacts 4.46″ low while the #2160 SBT impacts 3.88″ low. That’s a difference of only 0.58″ in spite of a huge difference in Ballistic Coefficient. If we compare out at 500 yards, then we have a [significant drop variance] of 14.27″ between these two bullets. [Editor: That difference could mean a miss at 500 yards.]
Distance to Your Prey is the Key Consideration
In a hunting situation, under 200 yards, having a difference of only .58” isn’t going to make or break us. But when elk hunting in wide open spaces it could mean everything.
The next time you’re choosing a bullet, give some thought about the distances you will be shooting. Sometimes B.C. isn’t everything. If you have any questions, please give the Sierra Bullets technicians a call at 800-233-8799.
May 21st, 2017
 A unique, comprehensive Cartridge Comparison Guide is available as a 340-page, spiral-bound book. Covering over 250 cartridges, the updated Second Edition of the Cartridge Comparision Guide is the product of many years of labor by Andrew Chamberlain, a Utah-based hunter. Andrew says his $36.95 Guide “compares every factory available cartridge from the 17 calibers up to the 50 caliber cartridges”. (Sorry, most wildcat cartridges are not covered.) Chamberlain’s Guide also compiles cartridge data from major ammunition manufacturers such as Barnes, Federal, Hornady, Norma, Nosler, Remington, Sierra, Swift, Weatherby, and Winchester. It shows the optimal velocity achieved for each bullet weight and calculates bullet energy, recoil, and powder efficiency. Large color photos illustrate handgun and rifle cartridges.
The Cartridge Comparison Guide provides data for thousands of cartridge/bullet/velocity combos. Quick reference data sheets and ballistics charts cover Trajectory, Velocity, and Energy out to 500 yards. The Cartridge Comparison Guide also offers a firearms lexicon, plus Appendices covering Cartridge Selection for Game Animals, Bullet Selection/Design, Bullet Expansion, Wound Channel Characteristics and more.
New Content in Second Edition of Cartridge Comparison Guide
The Cartridge Comparison Guide (Second Edition) costs $36.95 plus shipping and tax. CLICK HERE to visit the Online Store where you can order the 340-page book. Here’s what’s new in the Second Edition:
- Addition of Shotgun Ammunition (Both Slug and Shot loads).
- Momentum Calculation for all Rifle, Shotgun and Handgun loads.
- Integration of Shotgun Slug Ammunition with Center Fire Rifle Data Tables.
- Factory Load Summary Added (Shows manufacturers and loads produced).
- One factory load and one hand load for every bullet weight available in each cartridge.
- Over 90 pages of additional ballistics content (roughly 35% more than in First Edition).
April 26th, 2017
All 10s and Xs for record — that’s a very impressive 200-10X score card for young Lynzie Graham.
Here’s a “feel-good” story about a talented young shooter. We like to acknowledge the accomplishments of the “rising stars” in our sport. Lynzie Graham, a member of the U.S. F-Class Under-25 Team recently shot a perfect 200-10X at 600 yards, not dropping a point. That’s particularly impressive when you consider Lynzie shot her 600-yard “clean” using a factory rifle — a Savage Arms .308 Win F-TR rig.
Congratulations Lynzie Graham on your first 600-yard “clean” at the Texas State Qualifier in February 2017. Lynzie was shooting the Sierra 180gr MatchKing® #2220 with her Savage F-TR .308 Win. This August, Lynzie and other U.S. F-Class U-25 Team members will be competing at the F-Class World Championships (FCWC) hosted at the Connaught Ranges near Ottawa, Canada. Click image below for more information about the 2017 FCWC.
March 31st, 2017
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 uynderground tunnel. The results are show above — a FIVE HUNDRED Round group!
The tunnel testers sent five full boxes of bullets down-range. Here are 500 Shots shot in a 300 meter tunnel. The group size is 2.82 inches (that’s edge to edge of the farthest shots, less the bullet diameter). This was a pressure/velocity test for a commercial customer. The Cartridge was .308 Win, 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. Sierra offers free tours of the test tunnel as part of Sierra’s Factory Tour Program.
March 3rd, 2017
Ever wondered what caused a particular bulge or marking on a case? And more importantly, does the issue make the case unsafe for further use? Sierra Bullets Ballistic Technician Duane Siercks offers some insight into various issues and their causes in this article from the Sierra Blog.
Incipient Case-Head Separation
This is a Winchester .308 Win case that has a real issue. This case has a very obvious incipient case head separation in the process of becoming a complete failure.
This is most commonly caused by over-sizing the case causing there to be excess headspace on the case. After a few firings and subsequent re-sizing, this case is just about ready to come completely apart. Proper die adjustment is certainly a requirement here. Of course this case is not safe to reuse.
Excessive Pressure (Load Too Hot)
If you will notice in the picture of the case rim, there are two pressure signs to notice. First, look at the primer. It is basically flattened to about the max of what could be considered safe. If this was the only pressure sign noted, I would probably be fine with this load, but would constantly keep an eye on it especially if I was going to use this load in warmer temperatures. This load could easily cross into the “excess pressure” realm very quickly.
There is another sign of pressure that we cannot ignore. If you’ll notice, there is an ejector mark apparent that is located over the “R” of the R-P headstamp. This absolutely tells us that this load would not have been in the safe pressure range. If there were any of these rounds loaded, they should not be fired and should be dis-assembled. This case should not be reloaded.
Split Case-Neck
Here we have an R-P .22-250 case that has died the death. Everything looks fine with this case except the neck is split. This case must be tossed.
A split neck is a normal occurrence that you must watch for. It is caused by work-hardening of the brass. Brass cases get harder with age and use. Brand new cases that are stored for a period of time can become hard enough that they will split like this case within one to two firings. I have had new factory loads do the same thing. Then as we resize and fire these cases repeatedly, they tend to get harder and harder. Eventually they will split. The life of the case can be extended by careful annealing practices. This is an issue that would need to be addressed in an article by itself. Of course this case is no longer usable.
In the classes that I teach, I try to use examples like this to let the students see what they should be looking for. As always, if we can assist you, whether you are new to reloading or very experienced, contact us here at Sierra Bullets by phone at 1-800-223-8799 or by email at sierra@sierrabullets.com.
Dented Case Body
Here we have a Lake City 7.62×51 (.308 Win.) case with two heavy marks/dents in the case body.
This one may be a bit of a mystery. It appears as if this case may have been caught in the action of a semi-auto rifle when the firearm jammed or the case failed to clear during the cycling process. I probably would not reload this case just to prevent any feeding problems. This also appeared to be a factory loaded round and I don’t really see any pressure issues or damage to the case.
It is very important to observe and inspect your cases before each reloading. After awhile it becomes second nature to notice the little things. Never get complacent as you become more familiar with the reloading process. If ever in doubt, call Sierra’s Techs at 1-800-223-8799.
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