SAAMI – Sporting Arms and Ammunition Manufacturers’ Institute

Written by Sierra Bullets Ballistic Technician Philip Mahin

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. It consists of individual cartridges, 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 pamphlet.

Pressure_CartridgeThe 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. I have included a photo of a case (to the left) that was used in this method and you can see the ring left by the piston hole. What the book lists as the preferred method is the PSI 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. As far as I can tell and anyone else can tell me is that there is no correlation between them. An example of this is the 223 Remington cartridges 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 and you can see from at least one powder manufacturer that the 30-06 used both.

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. We use actual firearms to test data with so an example of our listed start load in the 308 Winchester using our 168gr MatchKing and Reloder-15 powder is 38.8gr or just round up to 39 grains. We found our accuracy at 42 grains with this combination and pressure signs at 43.6 grains. If you are to use the 1% rule and work up 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 from the 800 room every day. Till next time, be safe and enjoy your shooting.

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A Strange Thing Happened the Other Day!

Written by Sierra Bullets Ballistic Technician Rich Machholz

It all began innocently enough.  But there were clues.

Remember the Dasher project from earlier this year?

I had a big double 600 yard IBS match this past weekend and I needed to load at least 100 6mm Dashers for this match.   Unfortunately, every evening seemed to be spoken for, so where does the time come from?  We’ve all been in this position at one time or another.  So what do we do?  Why we make time of course!

A nephew plays football for the local high school and I try to go to his games when possible, but this Friday night just wasn’t going to work for me.  It was raining, but that didn’t deter my wife, so she went to the game and I stayed home to load.

I got all 100 Dasher cases resized without complications except my Forster Benchrest Dies didn’t want to eject the spent primers reliably, but I got the sizing die adjusted eventually and all went well to that point.

I didn’t have time to clean the cases so the next step was priming.  I normally use a Lee Auto Prime but for this operation the Lapua primer pockets are so tight I felt the Auto Prime was in jeopardy so I primed them with a Forster Co-Ax Primer Seater.  The Forster Co-Ax Primer works very well but is a little more difficult to load with primers.

It was time to charge the cases and my jug of Varget was handy, but getting lighter by the week.  Luckily Dashers don’t eat much.  In the interest of time, I setup a Lyman DPS powder dispenser to my load, set the auto repeat and began to charge cases.  The charges were fluctuating occasionally so I had to move the unit to a more solid setting which solved the issue, but interrupted progress.  I also felt it was dispensing slower than normal.  That happens when you are in a hurry.  Usually I can dump the powder, hit the repeat button, pick up a bullet set it in the case mouth, transfer it to the Co-Ax and seat it partially, lower it and turn the cartridge 180 degrees and finish seating the bullet.  That method has given me great concentricity over the years.  Is it necessary with the Co-Ax and dies?  Probably not, but old habits can be hard to break.

Because I was trying to make time I was dumping the powder faster than normal and it was bridging or worse yet, you try to double charge one that already has a charge.  If you don’t catch that condition you have a mess.  I experienced all of the above that evening.  Never fails, it just does not pay to load distracted or hurried.

I had just gotten a box of the newly run #1570 pointed 107 grain 6mm MatchKings and didn’t have time to sort them, so I loaded from the box.

I get to the match and have great relay draws.

Okay, I get all setup and have a hard time getting on target, but manage to figure that out before time expired.  Ready on the right, ready on the left, ready on the firing line, commence firing and the match begins.  About my third shot, the firing pin falls, but no recoil.  Uh-oh – no powder!

I lifted the bolt handle to clear the action and it’s auto eject time.  The case flies out and the bolt stops on the bolt stop.  Because I was able to lift the bolt with my thumb and fore finger it slipped from between my fingers right out of my hand, propelled rearwards by a small amount of unknown trapped gasses.  There was some force, but no explosion, just a dull pop like uncorking a bottle.  The bolt wouldn’t move its’ full travel forward or back afterwards due to a jammed bolt stop.  Hmm, go figure, but it had done its job.  A couple of taps on the bolt stop and problem solved temporarily, but a new pin will make it whole again.  We realigned the cocking piece to restore full bolt stroke and shot the next relay.  Beyond that no other damage.

We’ve all experienced firing uncharged cases and there is never any danger attached with ejecting one after the primer has been fired.  Most of the time the bullet doesn’t even exit the case.

Duds, which are fully loaded cartridges with defective ignition, should never be ejected right away due to the possibility of the “smoldering” powder charge igniting the ejected cartridge with the bolt unlocked or on the ground, causing a potentially catastrophic situation.

So what really happened?

Thanks to input from friends and competitors, we figure I failed to fully charge the case and only got a few kernels of powder in the case.  There was enough powder to force the bullet about 2 inches up the bore and enough pressure to obturate the case, sealing the chamber.  So when I lifted the bolt handle, the bolt body was able to move rearward unimpeded with some force.  Would waiting 60 seconds, 5 minutes or even 10 minutes let the pressure bleed off – I don’t know, but I can tell you this – lifting the bolt sure does.

Oh yes, the bullet was removed with an blunt cleaning rod, a shot of Kroil down the muzzle and a few taps of a dead blow hammer.

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A Record Breaking Rifle and Shooter


Mr. Barney M. Auston of Tulsa, Oklahoma with the rifle he built to break a National Bench Rest Shooters Association record and win the $250 cash award from Sierra Bullets manufacturers, which is being presented to him by Mr. John Zink, patron of bench rest shooting in Tulsa. (From the cover of Precision Shooting magazine May 1956)


On August 20, 1955, shooting at night in a registered shoot on the John Zink range near Tulsa, Oklahoma, Barney M. Auston of Tulsa broke the existing National Match Curse aggregate record and, as the first to do that in 1955, won the Sierra Bullets $250 cash award.  (Above) Mr. Auston is resting his hand on the rifle he built and shot to break the record with.

Mr. Auston’s winning aggregate for the National Match Course (five 10-shot groups at 100 yards and five 10-shot groups at 200 yards) was .4512 minutes of angle.  He also broke the 200 yard aggregate with an average f .4624 minutes of angel, beating the .4801 match m.o.a. record made by L.E. Wilson of Cashmere, Wash., at Buffalo, Wyoming, only a month earlier.

The rifle is built on an FN Mauser action with double set trigger, with a Hart stainless steel barrel, 30″ x 1 1/8″ and chambered for the .222 Remington cartridge.  The stock, made by Auston, has a Hydraulic bedder as made by L. F. Landwehr of Jefferson City, MO.  The scope is a 24 power 2 inch Unertl.

Mr. Auston shot 50 grain bullets, custom made by W. M. Brown of Augusta, Ohio, with .705″ Sierra cups and soft swedged.  His powder charge was 21 grains of 4198.

The rifle rests, both front and rear were also made by Mr. Auston.

Barney Auston, is a custom rifle maker in Tulsa who has fabricated the rifles used by many of the leading contenders in bench rest shooters in the Mid-Continent and Guild Coast Regions, and he has himself been one of those top contenders since competitive bench rest shooting started in that region.

Both of Mr. Auston’s records were broken again before the end of the 1955 shooting season and we suspect he will be trying harder than ever to regain his laurels in 1956.

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New Sierra Mobile Hits The Highway

Written by Sierra Bullets Media Manager Carroll Pilant

The Sierra mobile, which has been such a familiar vehicle at an assortment of matches around the US, has been replaced with a new 2015 Chevy Traverse. The maiden voyage for it was to Rockcastle. When I pulled out of Sierra’s parking lot, it had a grand total of 10 miles on it.

The old Sierra mobile (a Chevy Equinox) has 215,000 miles on it and still runs very well. That vehicle and I have spent many hours on the road, lots of nights in motels, and several nights in rest areas, just snoozing for 2 or 3 hours and continuing on our way just to keep from having to spend another night in a motel.  (My boss says he didn’t know they still had $19.95 a night motels, since I preferred to stay in motels that a door opens out where I could back the vehicle up to the door.) I have to admit, I have stayed in some pretty sleazebag motels. I carry a bottle of aftershave in my suitcase just to douse the curtains over the AC with if the smell is very bad. At least it will get you thru the night. I had a motel in Ely, NV. that I put a poncho on the bed and laid on it and finally when the druggies started fighting in the parking lot about 3 AM, I got up and drove to a rest area and slept for a couple more hours and went on to Reno, NV. for the Multigun Nationals. That motel room had a piece of barn tin nailed up to keep the door closed because it had been kicked open so many times.

I have seen my share of wrecks all across the US.  Four or five years ago, returning from the Multigun Nationals in Las Vegas, I pulled into a rest area just outside Flagstaff, Az. (the rest area is now closed down) and pulled into the first parking spot and slept for a couple of hours. I got up, went to the restroom, came back to the vehicle and was setting there with my eyes closed debating on sleeping a little longer or driving on. There was a tremendous crash right outside my door. A large van had jumped the curb and plowed into a tree about 2 foot in diameter just about 5 foot from the drivers door. The tree was completely embedded in the front of the van and the driver was unconscious. The driver door wouldn’t open, but the passenger door would. The driver was alive, but was in and out of consciousness.

I called 911 and the operator said there was no rest area there. I told her there was, that I was standing in it. She argued there wasn’t and I argued back there was. She got mad and sent me to her supervisor who also told me there was no rest area there. I argued there was. Then she finally said,” Yes there is, I just found it.”

The first county patrol car blew by about 10 minutes later and overshot the entrance and about 5 minutes later, returned. Then 2 highway patrol, 2 ambulances, and 2 firetrucks showed up. There was a pickup 2 spots down from me and the driver was still asleep even with all the lights and sirens. When he woke up, I guess he thought he was under arrest or something because he jumped out of the truck and stuck his hands in the air in the surrender position. One of the highway patrol asked him if he would like to leave and he said yes, so they moved patrol cars and firetrucks and he left in a hurry.

It appeared to the highway patrol that the driver involved in the crash was on drugs and they told me they were going to take him to a hospital, have him checked out, and then probably on to jail. I was trying to keep the driver conscious while waiting for the patrol and ambulance. I asked him if he was drunk or on drugs and he replied, “I have been trying to quit,” and passed out again. Another time, he raised his head up and said, “What the hell are you doing in my front room?” and passed out again.  It made for an interesting night and now, if I park in a rest area, I always park farther down the line, not in the first spot!

Another time, I was coming thru Oklahoma and, as always, there was a lot of traffic and some road construction. As it narrowed down to a one lane road, a really hefty woman with a man passenger came zipping by me and the semi in front of me. The concrete wall made her have to jerk it over, barely missing the semi. She crossed the road went thru the ditch and up a long steep bank with sumac flying like she was running a brush hog thru it. At the top of the bank, she literally made a U-turn, came flying back down the bank with the same results on the sumac, crossed in front of the semi and hit the concrete wall and sort of wobbled back out into lane of traffic. No one was hurt, but as we all went around her, the man was cussing her out so loud I could hear him as I drove by.

The new Traverse will see a lot of the same happenings in its future, I am sure. If you see me on the road, be sure and wave because I am either on my way to or from a match.

See you on the range!

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Ballistician Job Available at Sierra Bullets

Must Love Guns
Have you (or someone you know) always dreamed of working at Sierra Bullets in Sedalia, Missouri?

We are currently accepting applications for a second shift Ballistician. For more information, please visit

Read our tips on applying.

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2014 Brownell’s Rockcastle Pro Am 3-Gun Championship

Written by Sierra Bullets Media Relations Manager Carroll Pilant

The Brownell’s Rockcastle Pro Am 3-Gun Championship is actually 2 matches in one. The matches will take place August 22 – 24, 2014, at the Rockcastle Shooting Center at Park Mammoth Resort in Park City, Kentucky. There was the Amateur Division, which was shot on Friday, August 22 and Saturday, August 23, with the awards on Saturday night. This division had about 250 shooters. Some of the top 3-gun shooters in the nation put on clinics for the amateur (Am) shooters at the end of each day providing them with a wealth of knowledge on how the Pros shoot. The amateur (Am) shooters shot similar, but less complicated stages than the Pro shooters.

The Professional Division was shot on Friday, Saturday and Sunday with the awards on Sunday afternoon. The Pro division also had about 250 shooters. The temperature was very warm with very high humidity. Within minutes you were soaked, with sweat running in your eyes while you were trying to shoot. This match had a 100 second time out, which means if you do not have all your targets engaged at the end of 100 seconds, you are penalized with a failure to engage and neutralize for each target remaining. Several of the top shooters even managed to time out on some stages. The stages were interesting in that you had a choice of which firearms you could use. There were a lot of steel targets that you could use your choice of either a handgun or shotgun on with some of the paper targets that you could use rifle or handgun on. There was even a plate rack that you could use rifle, pistol or shotgun on. Every shooter had his own preference and you would see a large variance of the ways it was shot just in one squad. Open shooters seemed to opt for the shotgun in a lot of places where tactical shooters would opt for either a shotgun for the first 9 rounds (what they were allowed to start with in the shotgun) and then transfer to the handgun, so they wouldn’t have to load the shotgun. With the 100 second timeout, every second counted.

Photo Courtesy of Adams Arms shooter, Becky Yackley

Team ArmaLite shooter, Greg Jordan.  Photo courtesy of Adams Arms shooter, Becky Yackley.

Despite the heat and humidity, Greg Jordan, with ArmaLite was the top shooter in the Tactical Scope Division of the Pro Side. Congratulations to Greg on his win there and here’s to many future wins with the 77 grain MatchKing #9377G.

See you all at the Generation 3 Match here in Missouri. Hopefully the weather will be somewhat cooler. If you see any of us Sierra people there, be sure and say “hello.”

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Was Anything Wrong With The .244?

Written by Sierra Bullets Ballistic Technician Paul Box

The year was 1955. A time of carhops, drive-in movies and Buffalo Bob. It was also the year that Winchester introduced the .243 and Remington counter-punched with the .244. The .243 was based off the time proven .308 case while Remington chose the old war horse, the 7×57.

We’ve all read countless times how Winchester chose the 1-10″ twist, while Remington adopted the 1-12″ for their .244. The first complaint in the gun magazines of that era was how the faster twist Winchester choice could handle 100 gr. bullets, and Remington‘s factory offering was a 95 gr. bullet.

The first complaint I remember reading was that the 100 gr. was better suited for deer- sized game and the 1-12″ wouldn’t stabilize bullets in this weight range. Now, let’s look at this a little closer. Anybody that thinks a 100 gr. is a deer bullet and a 95 gr. isn’t, has been drinking to much kool-aid. In all honesty, it’s all about bullet construction and Remington had constructed the 95’s with light game in mind. In other words, Remington got it right, but due to a lack of knowledge at the time on both bullet construction and stability, the .244 never gained the popularity it deserved. At that time, Sierra had the 100 gr. SMP and Hornady offered a 100 gr. RN that would both stabilize in the slower 1-12″ twist.

Another classic example of how the popularity of a cartridge suffered due to a lack of knowledge.

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