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October 13th, 2014
by Philip Mahin, Sierra Bullets Ballistic Technician
This article first appeared in the Sierra Bullets Blog
The ANSI / SAAMI group, short for “American National Standard Institute” and “Sporting Arms and Ammunition Manufacturers’ Institute”, have made available some time back the voluntary industry performance standards for pressure and velocity of centerfire rifle sporting ammunition for the use of commercial manufacturers. [These standards for] individual cartridges [include] the velocity on the basis of the nominal mean velocity from each, the maximum average pressure (MAP) for each, and cartridge and chamber drawings with dimensions included. The cartridge drawings can be seen by searching the internet and using the phrase ‘308 SAAMI’ will get you the .308 Winchester in PDF form. What I really wanted to discuss today was the differences between the two accepted methods of obtaining pressure listings. The Pounds per Square Inch (PSI) and the older Copper Units of Pressure (CUP) version can both be found in the PDF pamphlet.
Image by ModernArms, Creative Common License.
 CUP Pressure Measurement
The CUP system uses a copper crush cylinder which is compressed by a piston fitted to a piston hole into the chamber of the test barrel. Pressure generated by the burning propellant causes the piston to move and compress the copper cylinder. This will give it a specific measurable size that can be compared to a set standard. At right is a photo of a case that was used in this method and you can see the ring left by the piston hole.
PSI Pressure Measurement
What the book lists as the preferred method is the PSI (pounds per square inch or, more accurately, pound-force per square inch) version using a piezoelectric transducer system with the transducer flush mounted in the chamber of the test barrel. Pressure developed by the burning propellant pushes on the transducer through the case wall causing it to deflect and make a measurable electric charge.
Q: Is there a standardized correlation or mathematical conversion ratio between CUP and PSI values?
Mahin: As far as I can tell (and anyone else can tell me) … there is no [standard conversion ratio or] correlation between them. An example of this is the .223 Remington cartridge that lists a MAP of 52,000 CUP / 55,000 PSI but a .308 Winchester lists a 52,000 CUP / 62,000 PSI and a 30-30 lists a 38,000 CUP / 42,000 PSI. It leaves me scratching my head also but it is what it is. The two different methods will show up in listed powder data[.]
So the question on most of your minds is what does my favorite pet load give for pressure? The truth is the only way to know for sure is to get the specialized equipment and test your own components but this is going to be way out of reach for the average shooter, myself included. The reality is that as long as you are using printed data and working up from a safe start load within it, you should be under the listed MAP and have no reason for concern. Being specific in your components and going to the load data representing the bullet from a specific cartridge will help get you safe accuracy. [With a .308 Winchester] if you are to use the 1% rule and work up [from a starting load] in 0.4 grain increments, you should be able to find an accuracy load that will suit your needs without seeing pressure signs doing it. This is a key to component longevity and is the same thing we advise [via our customer service lines] every day. Till next time, be safe and enjoy your shooting.
October 11th, 2014
Sierra Bullets has just added extensive load data for the 300 AAC Blackout (300 BLK) cartridge. Developed for the AR15 platform, the 300 BLK offers AR shooters a large-caliber option in both subsonic and supersonic variants. The 300 BLK can be made from modified .223 Rem brass or necked-up .221 Fireball cases. We like to form our .300 BLK brass by necking-up the excellent Lapua .221 Fireball brass.
CLICK HERE for Sierra Load Data for 300 AAC Blackout (PDF File)
Sierra Has 5 Pages of Load Data for the 300 AAC Blackout. Here is one sample page:
Sierra Cartridge Comments: 300 AAC Blackout
The 300 AAC Blackout (300 BLK, or 7.62x35mm) was created by Advanced Armament Corp. and Remington in order to provide the military with a way to shoot .30 caliber bullets from the M4 platform with only a barrel change. It has since become popular for a wide range of uses including hunting and home defense.
The cartridge shares case-head dimensions and body taper with the .223 Remington. Not only does this allow for compatibility with existing magazines and bolts, but it allows reloaders to form 300 BLK brass from the vast supply of 5.56mm or .223 cases. However, since .223/5.56 cases need to be cut-down and reformed, it can be simpler to neck up .221 Fireball brass.
The 300 AAC Blackout is similar to previous wildcats, such as the .30-221 and .300 Fireball, as well as the proprietary 300 Whisper®. However the 300 BLK was the first SAAMI-approved (and standardized) cartridge of this type. Moreover, any company is free to make firearms or ammunition for the 300 BLK.
300 AAC Blackout is popular with hunters, who may not be allowed to legally hunt with .223 in their state, and who prefer .30-caliber bullets for medium-sized game. It provides similar effectiveness to the 7.62×39mm or the slightly more powerful 30-30 cartridges, while working in the more up-to-date AR15 platform. Effective range for hunting is about 100-150 yards.
August 21st, 2014
How would you like to have the entire collection of Sierra rifle and pistol bullets at your fingertips, complete with bullet Ballistic Coefficients (BCs) and parts numbers? Well we’ve got you covered. Sierra publishes a handy PDF chart that displays all of Sierra’s popular projectiles, from .20 caliber all the way up to .50 caliber. CLICK HERE to download Sierra Bullets Chart.
CLICK Image to Download PDF Chart with All Sierra Bullet Types (2 MB file)
Detail Sample from Chart
Order Free Sierra Catalog
You can also get a free, hard copy poster with all Sierra’s bullet types. The current Sierra Bullets catalog has a printed insert that folds out into a large poster for your loading room or workshop. To order the current Sierra Catalog (with fold-out poster), visit Sierra’s Catalog Request Page.
August 15th, 2014
“Where are the bullets, where is the powder?” (ad infinitum) is what you hear from shooters around the country these days. Well we can’t promise more powder, but Sierra Bullets has invested in machinery that should help increase bullet output. Sierra has acquired a 550-ton rated extrusion press that should pump out lead wire faster (for bullet cores). Sierra tells us: “This is a lead extrusion press we had shipped in from the state of Washington. We are diligently working on getting this thing set up and pumping more lead into our process.”
If you’re curious how this beast works, Alan Slocum posted an explanation: “It works kinda’ like this”, referring to the photo below. Sierra’s big machine uses a horizontal hydraulic ram instead of the push-down yellow Play-Doh lever, but yes the basic principle is the same.
May 13th, 2014
With so much attention given to the newest hardware, and most recent reloading innovations, we sometimes forget that Benchrest shooting, as a competitive sport, has been around for quite a long time. And some of those “old school” shooters managed to put together some pretty fine groups even without 21st Century gadgets and gear.
Click Photo to See Larger Version.
Here are some of the founding fathers of benchrest shooting, in a photo taken nearly six decades ago (4/3/1955). Men’s fashion has changed a bit over the years. Tony Boyer notwithstanding, you won’t find so many Stetsons at a shooting match these days. Courtesy of Sierra Bullets, here’s a “throwback” image of Benchrest shooters at the Brea, California “Round-Up” Shoot April 2 – 3, 1955. Left to right are: Frank Snow, (Founder of Sierra Manufacturing Company), John Moffit, K. E. “Smitty” Smith (NBRSA Director), Al Christie, E.F. Stewart, Jack Rice (sitting), I. F. Jack Williams, Lindsey King (behind Williams), Don “6mm” Smith, Frank Hemsted, and Art L. Elliott.
If you like this sort of “trip down memory lane”, visit Sierra Bullets’ Facebook page. Every Thursday morning, Sierra publishes a “Throwback Thursday” photograph from some decades past, together with a short featurette on the shooting-related item/person in the photo.
April 7th, 2014
Matt Reams, the V.P. of Sales for Sierra Bullets, recently addressed the burning question in the minds of many shooters these days: “Where did all the .22LR rimfire ammo go — why can’t I find any?” Here is Matt’s answer, from the knowledgeable perspective of a firearms industry executive.
 Why Can’t I Find .22 LR Ammunition? by Matt Reams
Even though Sierra Bullets does not make .22 LR ammo or projectiles, we are constantly asked “Why can’t I find any .22 LR ammo anywhere?” Even the conspiracy theorists are at a loss on this one as they can’t even blame it on the government. They toss around thoughts of warehouses full of .22 LR rotting away just to keep it out of their hands, but that does not seem very realistic – even to them.
So what is going on here? Why is it that 1.5 years later, the shelves are still empty and bricks of .22 LR can still be seen selling for upwards of $75-$100 at gun shows? I do not believe there is one answer, but rather a few. Here are my opinions on the matter, for what they are worth.
Hoarders – Some people are piling it away in their basements, garages, bunkers, and under their beds due to fear of not being able to find it again. This is not a huge factor in it, but it is still a factor to some degree. When these hoarders can’t find it on shelves, it only panics them more and causes them to buy even more when they do find it.
Gougers – These are the guys who prey on the fear of the hoarders. These are the guys that wait in line at Wal-Mart at 3 a.m. to buy up the daily allotment that Wal-Mart puts out at normal retail prices and then double or triple their price on the weekend gun show circuit. Again, not a huge factor, but keeping the shelves looking empty which keeps the panic level higher for those that are looking.
Demand – Now we are getting to the real meat of the issue. You hear manufactures say they are running 24/7 on their rimfire lines which is putting somewhere around 25-30 million rounds PER DAY (estimate on my part from numbers I have heard from the big rimfire guys) into the market – so how can there be a shortage? I have asked this myself – until we start doing even a little basic math. You hear all kind of numbers about how many firearms owners are in the USA, but you hear 70-80 million quite often. So for the sake of us not arguing that number – let’s cut it to 35 million. Do you know a gun owner that does not own at least one firearm chambered in .22 LR? Do you know any that are not looking for .22 LR ammo or would at least buy some if they saw it for normal prices? How many would they buy when they found it? A lot – right? But again, just to keep the argument on the low end, let’s say they would all be satisfied with just a single 500 pack. 35 million multiplied by 500 .22 LR rounds for them all – is 17.5 BILLION rounds. Let that sink in. Even at 25 million rounds being made PER DAY – that is 1.92 years’ worth of production.
Starts making some sense then doesn’t it? Hoarding and panic emptied the shelves. Gougers try and keep them empty and demand does keep them empty. Then factor in that I probably cut the real number of 22 LR shooters in half and probably underestimated the amount everyone would buy if they found it at normal prices by 300% and you can see how deep the problem really is and why it is not going to go away tomorrow. It also does not take into account the world market – just the USA.
How will it get better? Slowly. The hoarders will get to a point that they feel they have enough or will run out of money. The shelves will start getting enough on them that the gougers cannot buy it all. This will make people stop paying $50-$75 for a brick at gun shows. That will make it less profitable for the gougers to spend their money on and they will stop. The shelves will start to have product again which will ease people’s fears and get them back to buying what they need today instead of what they need for the decade. There is no fast answer.
Are the manufactures hiring people for extra shifts and adding capacity – sure they are. But it is easy to just expect them to ramp up production overnight to take care of our needs, but that is just not realistic. We get the same thing here. The market certainly has not grown 500% so what happens when companies add all that super expensive equipment when things get back to normal? They take a bath on it for sure and waste capital that they could have used to improve their company in a way that makes them stronger. Instead they just added equipment they may never need again and have to mothball while they lay off workers they no longer need. Not a great way to run a business and not a fair way to treat employees.
We all just have to trust that it will get better, do not buy more than we need and wait it out. It will not get better overnight. It will start out with a box here and there and then a few and then slowly the shelves will get back to having all the supply and selection we picky consumers are accustomed to and will certainly appreciate much more than we ever did before… if only for a little while.
December 20th, 2013
The 300 AAC Blackout (300 BLK, or 7.62x35mm) was created by Advanced Armament Corp. and Remington in order to provide the military with a way to shoot .30-caliber bullets from the M4 carbines with only a barrel change. It has since become popular with AR shooters for a wide range of uses including hunting and home defense. With the increased popularity of this cartridge, folks have been looking for reliable 300 BLK load information. Now, thanks to Sierra Bullets, we have some good load data for the 300 AAC Blackout. Sierra has released a FREE 6-page Load Guide for this cartridge, as part of the Sierra Reloading Manual (5th Edition).
CLICK HERE for Sierra 300 AAC Blackout Load DATA (PDF Format).
Here is ONE of SIX Pages in the Sierra Load Sheet for 300 AAC Blackout
About the 300 AAC Blackout (300 BLK)
The 300 AAC Blackout cartridge shares case-head dimensions and body taper with the .223 Remington. Not only does this allow for compatibility with existing magazines and bolts, but it allows reloaders to form their own brass from cut-down 5.56×45 mm or .223 Rem cases. You can also form 300 Blackout cases by necking-up .221 Fireball brass. Take Note: Lapua has started producing .221 Fireball brass — this should be available in the USA by early April.
The 300 AAC Blackout is a similar concept to previous wildcats, such as the 30-221 and 300 Fireball, as well as the proprietary 300 Whisper®, except that 300 BLK was the first to be a SAAMI-approved cartridge and any company is free to make firearms or ammunition.
300 AAC Blackout is also finding use with hunters, who may not have been able to legally hunt with .223 in their state, and who prefer .30 caliber bullets for medium-sized game. It provides similar effectiveness to the 7.62×39 or the slightly more powerful .30-30 cartridges except works in the more up-to-date AR-platform rifles. Effective hunting range is about 150 yards. Some innovators, such as Dave Whitford, have also experimented with the 300 BLK for Across-the-Course competition. READ Whitford story in Rifleman’s Journal..
November 2nd, 2013
The last primary lead smelter facility in the United States will be closing soon. The Doe Run Company smelter in Herculaneum, Missouri has been operating since 1892. The facility will be closed permanently under pressure from the EPA. According to MSNBC.com: “Doe Run Co. was ordered by the EPA to install new pollution control technologies needed to reduce sulfur dioxide and lead emissions as required by the Clean Air Act. The company will instead close its lead smelter.”
Doe Run started life in 1864 as the St. Joseph Lead Company, better known as St. Joe, which started lead mining on a small scale in southeastern Missouri. In 1892 it started up its smelter in Herculaneum, where all smelting was consolidated in 1920.
Cause for Concern? Our readers have been concerned that the closure of the Doe Run smelter will lead to serious shortages in raw materials for bullet-making. Readers fear that bullet-makers won’t be able to source lead, and so the output of bullets and ammo would be reduced. Curtailed bullet production would lead to higher prices, it is feared.
As it turns out, the situation is not as dire as it seems. At least one bullet-maker says the Doe Run smelter closure will have no immediate effect on its raw material supply chain.
Sierra Bullets Responds: Lead Smelter Closure Should Not Cause Supply Shortage
Addressing the issue of supply shortages, Sierra Bullets posted a notice in the Sierra Blog on November 1, 2013. Sierra Bullets Plant Engineer Darren Leskiw stated that the Doe Run smelter closure should create no problems for his company because it uses only recycled lead:
We have had many customers contact us about the closing of the last primary lead smelting facility in the USA. This facility is operated by Doe Run and is located in Herculaneum, Missouri and is just about a 3-hour drive from our facility in Sedalia, Missouri.
The main question asked is “Will this shut down your supply of lead?” The answer to that is no. First, Sierra buys lead from several different vendors to maintain constant supply. Second, this facility only smelts primary lead or lead ore. This is lead ore that has just been brought out of the earth. Sierra uses no primary lead at all and never has, so we use nothing directly from this facility. The lead we buy from Doe Run comes from their recycling facility in Boss, MO that is about 90 miles away from the smelter that is closing.
The facility we buy from is still going strong and delivering to us as scheduled. The lead from this facility is from recycled lead, mostly coming from car batteries. This is a continuing “in and out” cycle for them and the smelter closing will not affect this facility.
Our supply should not be in jeopardy and we do not anticipate any changes in our supply chain at this time. Could the lack of primary lead create a little more demand for recycled lead? Sure, but how much is unknown. Could this increase in demand also create an increase in price? Sure, but again, by how much is unknown at this time.
There are many other primary lead smelters in the world and so the flow of primary lead will not be shut off. Where there is a need for primary lead, I am sure there will be a salesman more than happy to pick up the business. In short, we do not see any reason for alarm. We expect our supply to continue and keep feeding our production lines which are still running 24 hours per day to return our inventory levels to where they should be.
Lead Smelting Operations Have Moved to Mexico
Posting on SnipersHide.com, one industry insider says shooters should not be overly concerned about the Doe Run shut-down, because smelting is still being done in nearby Mexico:
“The lead industry has been transitioning out of the United States for over a decade now. 85% of the lead smelting industry capacity migrated over the Mexican border where there are [fewer environmental regulations]. The remainder of production capacity will be online and running by the third quarter of 2014. There has been no production disruption to speak of in obtaining lead or lead products. The auto battery industry among others has prepared for this eventuality for some time….
The last lead smelter closing in December did not have enough capacity to supply even 10% of the battery industry much less the ammunition industry. The lead being used in ammunition today hasn’t been coming from the United States for years already. The closing of that plant will not have any appreciable effect on lead availability at all. There is a great deal of lead processed here being extruded, made into shot, converted to wire, etc., but the smelting operation is only one part of the production process.”
June 24th, 2013
Colt’s Manufacturing Company LLC (Colt) is introducing a line of ammunition for Colt tactical and competition rifles. This new Colt-branded “Hunting and Defence Match” ammo will be manufactured by Black Hills Ammunition. The initial offerings are designed for rifles chambered for 5.56×45 NATO and will feature 55gr and 77gr Sierra match bullets. According to the Guns.com Blog: “The 77-grain cartridge may strike a few people as somewhat familiar. It is for most purposes Black Hills MK 262 77-grain ammo… considered by many to be the best factory-loaded 5.56 NATO ammunition on the market.”
Colt Claims Ammo Will Shoot 1-MOA Groups at 500 Yards
Colt says its ammunition will deliver long-range accuracy. During the development process, this line of Colt ammo was ballistically tested in Colt rifles with a requirement of consistent five-shot, one-MOA (5″) groups at 500 yards. Colt calls this the “triple-nickel” standard (5 shots, 5″, 500 yards). Colt claims that the “Triple Nickel” capability of its ammo “assures the experienced shooter incredible performance right out of the box, with no need for load development or experimentation.”
Holding 1-MOA at 100 yards is not that exceptional. But maintaining 1-MOA groups at 500 yards would be impressive indeed. This would require consistent powder charges and tight bullet-seating length tolerances to keep vertical dispersion to a minimum. It will be interesting to test the Colt-branded ammo when it hits the market and see if it works as well as claimed.
“We’re very proud of the ‘Triple Nickel’ requirement of this ammunition,” said said Joyce Rubino, Vice President of Marketing for Colt’s Manufacturing: “Our goal with Black Hills was to bring to market a superior line of ammunition for sport shooters to use in Colt rifles, and we feel we have achieved this through the partnership with Black Hills.”
June 15th, 2013
 With bullets in short supply and prices rising, here’s an opportunity for you folks located in the middle of the country who can visit Missouri. Sierra offers discounted bullets at its Factory Outlet store in Sedalia, Missouri. Sierra says: “If you happen to be in our neck of the woods, you can purchase available bullet seconds and our full line of products directly from our outlet store”.
View Sierra Bullets Seconds PRICE LIST
Sierra’s Factory Outlet inventory is constantly changing and no guarantees are made as to product availability. Bullet seconds are sold by the pound and are limited to 100 pounds per bullet type and a total of 300 pounds per day per person. There is a limit of 25 pounds of mixed bullets per day. Bullet seconds are for private consumption and not for resale! Factory seconds may include blemished bullets and mixed bullets, so weigh and measure each bullet prior to loading! Factory seconds must be picked up in person and will not be shipped.
For more information, call Sierra at (888) 223-3006 or send email to: sierra[at]sierrabullets.com .
Story tip by EdLongrange. We welcome reader submissions.
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