Precision Benchrest and F-Class shooters favor premium brass from Lapua, Norma, Peterson, or RWS. (Lake City also makes quality brass in military calibers.) Premium brass delivers better accuracy, more consistent velocities, and longer life. Shooters understand the importance of good brass, but many of us have no idea how cartridge cases are actually made. Here’s how it’s done.
The process starts with a brass disk stamped from strips of metal. Then, through a series of stages, the brass is extruded or drawn into a cylindrical shape. In the extrusion process the brass is squeezed through a die under tremendous pressure. This is repeated two or three times typically. In the more traditional “draw” process, the case is progressively stretched longer, in 3 to 5 stages, using a series of high-pressure rams forcing the brass into a form die. While extrusion may be more common today, RWS, which makes some of the most uniform brass in the world, still uses the draw process: “It starts with cup drawing after the bands have been punched out. RWS cases are drawn in three ‘stages’ and after each draw they are annealed, pickled, rinsed and subjected to further quality improvement measures. This achieves specific hardening of the brass cases and increases their resistance to extraordinary stresses.” FYI, Lapua also uses a traditional draw process to manufacture most of its cartridge brass (although Lapua employs some proprietary steps that are different from RWS’s methods).
After the cases are extruded or drawn to max length, the cases are trimmed and the neck/shoulder are formed. Then the extractor groove (on rimless cases) is formed or machined, and the primer pocket is created in the base. One way to form the primer pocket is to use a hardened steel plug called a “bunter”. In the photos below you see the stages for forming a 20mm cannon case (courtesy OldAmmo.com), along with bunters used for Lake City rifle brass. This illustrates the draw process (as opposed to extrusion). The process of draw-forming rifle brass is that same as for this 20mm shell, just on a smaller scale.
River Valley Ordnance explains: “When a case is being made, it is drawn to its final draw length, with the diameter being slightly smaller than needed. At this point in its life, the head of the draw is slightly rounded, and there are no provisions for a primer. So the final drawn cases are trimmed to length, then run into the head bunter. A punch, ground to the intended contours for the inside of the case, pushes the draw into a cylindrical die and holds it in place while another punch rams into the case from the other end, mashing the bottom flat. That secondary ram holds the headstamp bunter punch.
This video employs DEFORM-2D software to show the draw process for brass casings.
The headstamp bunter punch has a protrusion on the end to make the primer pocket, and has raised lettering around the face to form the headstamp writing. This is, of course, all a mirror image of the finished case head. Small cases, such as 5.56×45, can be headed with a single strike. Larger cases, like 7.62×51 and 50 BMG, need to be struck once to form a dent for the primer pocket, then a second strike to finish the pocket, flatten the head, and imprint the writing. This second strike works the brass to harden it so it will support the pressure of firing.”
Thanks to Guy Hildebrand, of the Cartridge Collectors’ Exchange, OldAmmo.com, for providing this 20mm Draw Set photo. Bunter photo from River Valley Ordnance.
Precision Benchrest and F-Class shooters favor premium brass from Lapua, Norma, Peterson, or RWS. (Lake City also makes quality brass in military calibers.) Premium brass delivers better accuracy, more consistent velocities, and longer life. Shooters understand the importance of good brass, but many of us have no idea how cartridge cases are actually made. Here’s how it’s done.
The process starts with a brass disk stamped from strips of metal. Then, through a series of stages, the brass is extruded or drawn into a cylindrical shape. In the extrusion process the brass is squeezed through a die under tremendous pressure. This is repeated two or three times typically. In the more traditional “draw” process, the case is progressively stretched longer, in 3 to 5 stages, using a series of high-pressure rams forcing the brass into a form die. While extrusion may be more common today, RWS, which makes some of the most uniform brass in the world, still uses the draw process: “It starts with cup drawing after the bands have been punched out. RWS cases are drawn in three ‘stages’ and after each draw they are annealed, pickled, rinsed and subjected to further quality improvement measures. This achieves specific hardening of the brass cases and increases their resistance to extraordinary stresses.” FYI, Lapua also uses a traditional draw process to manufacture most of its cartridge brass (although Lapua employs some proprietary steps that are different from RWS’s methods).
After the cases are extruded or drawn to max length, the cases are trimmed and the neck/shoulder are formed. Then the extractor groove (on rimless cases) is formed or machined, and the primer pocket is created in the base. One way to form the primer pocket is to use a hardened steel plug called a “bunter”. In the photos below you see the stages for forming a 20mm cannon case (courtesy OldAmmo.com), along with bunters used for Lake City rifle brass. This illustrates the draw process (as opposed to extrusion). The process of draw-forming rifle brass is that same as for this 20mm shell, just on a smaller scale.
River Valley Ordnance explains: “When a case is being made, it is drawn to its final draw length, with the diameter being slightly smaller than needed. At this point in its life, the head of the draw is slightly rounded, and there are no provisions for a primer. So the final drawn cases are trimmed to length, then run into the head bunter. A punch, ground to the intended contours for the inside of the case, pushes the draw into a cylindrical die and holds it in place while another punch rams into the case from the other end, mashing the bottom flat. That secondary ram holds the headstamp bunter punch.
This video employs DEFORM-2D software to show the draw process for brass casings.
The headstamp bunter punch has a protrusion on the end to make the primer pocket, and has raised lettering around the face to form the headstamp writing. This is, of course, all a mirror image of the finished case head. Small cases, such as 5.56×45, can be headed with a single strike. Larger cases, like 7.62×51 and 50 BMG, need to be struck once to form a dent for the primer pocket, then a second strike to finish the pocket, flatten the head, and imprint the writing. This second strike works the brass to harden it so it will support the pressure of firing.”
Thanks to Guy Hildebrand, of the Cartridge Collectors’ Exchange, OldAmmo.com, for providing this 20mm Draw Set photo. Bunter photo from River Valley Ordnance.
Do you compete in rimfire benchrest, silhouette, or NRL22 matches? Then you’ll want to check out the Shooting Sports USA .22 LR Ammo Roundup on the SSUSA.org website. That article covers .22 LR ammunition from Lapua, ELEY, SK, RWS, Norma, Wolf, and Aquila. Notably there’s a detailed discussion of Lapua’s new Long Range and Super Long Range ammo. In addition, SSUSA confirms that SK ammo (made in Germany by Nammo, parent of Lapua) and Wolf Match Target ammo (made by ELEY) both offer quite good performance for a moderate price.
The article notes that there is a much wider range of .22 LR ammo types available now than a few years ago. It’s not just a choice between cheap products and high-end match ammo. As SSUSA explains: “It used to be that .22 LR was either quite expensive match grade ammo, or it was cheap plinking or hunting ammo. Today, competitors have choices in grades of .22 LR match ammunition to suit their pocketbook or firearms.” We’ve seen good results with relatively inexpensive Norma Tac-22, and the SSUSA article says that SK performs well above its price level.
Seven Brands of .22 LR MATCH AMMUNITION
Lapua Super Long Range and Long Range .22 LR
Lapua Super Long Range and Long Range ammunition comes from Finland, and is designed for the growing long-range rimfire disciplines with targets at 100-300 yards. Lapua says this ammo delivers very low ES and SD numbers. Our friend F-Class John has tested this ammo and confirmed it performs very well (SEE video above). “Each production lot of Lapua’s new rimfire products are test-fired in 50-round groups for dispersion”, Capstone’s Marketing Director, Geoff Esterline, said. “The results determine whether it makes Super Long Range or Long Range packaging.”
ELEY .22 LR Ammunition
ELEY has long been a top choice for .22 LR competition — both position shooting and benchrest. ELEY now offers 11 different varieties of .22 LR match ammunition, ranging in price from $7 (Benchrest Outlaw) to $20 (ELEY Tenex). If you compete in the rimfire benchrest, you should definitely try some ELEY ammo.
SK .22 LR Ammunition
Numerous .22 LR ammunition types are offered by SK, suitable for a variety of disciplines — from NRL22 to Biathlon. Generally cheaper than ELEY Match ammo, SK offers good “bang for the buck”. F-Class John says it performs great considering the price. The SSUSA article notes that: “German manufacturer SK has eight match-grade .22 LR offerings, including two for pistols, one for semi-automatic rifles, and one for frigid, wintertime conditions.”
RWS .22 LR Ammunition
Sometimes hard to locate at vendors in the USA, RWS is popular among European competition shooters. The top-tier RWS ammo is a choice of many competitive shooters. RWS currently offers nine Premium Line .22 LR varieties and three Professional Line offerings. The SSUSA tester noted that RWS Rifle Match ammo shot great in his Bergara BMR, shooting one-ragged-hole groups at 50 yards and about one MOA at 100 yards. That’s great performance for $10/box ammo.
Norma .22 LR Ammunition
Norma recently introduced XTREME LR-22, a new type of competition rimfire ammo with a radical new bullet. This unique, patented bullet design has a special base with a cone (see diagram). Norma claims that this “rocket tail” design reduces drag by creating less negative pressure at the back end of the bullet. It will be interesting to see how this new bullet design works in rimfire ELR competition.
Wolf .22 LR Ammunition
SSUSA says that Wolf Match Target is a top performer in the under-$10 per box category. This is because, according to SSUSA: “It is manufactured by ELEY in England (and loaded with Vihtavuori powder) and re-branded, if online information is correct.” Wolf Match Target is available from Target Sports USA for $74.99 per thousand ($0.15 per round).
Aguila .22 LR Ammunition
Made in Mexico, Aguila .22 LR rimfire ammo is the bargain item among the seven ammo-makers featured by SSUSA. It is widely available at very affordable prices.
We wouldn’t choose Aguila for a benchrest or three-position match, but it could be more than adequate for a local NRL-22 match or a steel-target competition at relatively short range. Aguila .22 LR ammunition starts at under $3.00 per box. And right now Midsouth offers a 2000-round Case of Aguila for just $114.99. That works out to just $2.87/box or six cents per round.
Do you compete in rimfire benchrest, silhouette, or NRL22 matches? Then you’ll want to check out the Shooting Sports USA .22 LR Ammo Roundup released last week. That article covers .22 LR ammunition from Lapua, ELEY, SK, RWS, Norma, Wolf, and Aquila. Notably there’s a detailed discussion of Lapua’s new Long Range and Super Long Range ammo. In addition, SSUSA confirms that SK ammo (made in Germany by Nammo, parent of Lapua) and Wolf Match Target ammo (made by ELEY) both offer quite good performance for a moderate price.
The article notes that there is a much wider range of .22 LR ammo types available now than a few years ago. It’s not just a choice between cheap products and high-end match ammo. As SSUSA explains: “It used to be that .22 LR was either quite expensive match grade ammo, or it was cheap plinking or hunting ammo. Today, competitors have choices in grades of .22 LR match ammunition to suit their pocketbook or firearms.” We’ve seen good results with relatively inexpensive Norma Tac-22, and the SSUSA article says that SK performs well above its price level.
Seven Brands of .22 LR MATCH AMMUNITION
Lapua Super Long Range and Long Range .22 LR
Lapua Super Long Range and Long Range ammunition comes from Finland, and is designed for the growing long-range rimfire disciplines with targets at 100-300 yards. Lapua says this ammo delivers very low ES and SD numbers. Our friend F-Class John recently tested this ammo and confirmed it performs very well (SEE video above). “Each production lot of Lapua’s new rimfire products are test-fired in 50-round groups for dispersion”, Capstone’s Marketing Director, Geoff Esterline, said. “The results determine whether it makes Super Long Range or Long Range packaging.”
ELEY .22 LR Ammunition
ELEY has long been a top choice for .22 LR competition — both position shooting and benchrest. ELEY now offers 11 different varieties of .22 LR match ammunition, ranging in price from $7 (Benchrest Outlaw) to $20 (ELEY Tenex). If you’re in the rimfire benchrest game, you should definitely try some ELEY in your rifle.
SK .22 LR Ammunition
Numerous .22 LR ammunition types are offered by SK, suitable for a variety of disciplines — from NRL22 to Biathlon. Generally cheaper than ELEY Match ammo, SK offers good “bang for the buck”. F-Class John says it performs great considering the price. The SSUSA article notes that: “German manufacturer SK has eight match-grade .22 LR offerings, including two for pistols, one for semi-automatic rifles, and one for frigid, wintertime conditions.”
RWS .22 LR Ammunition
Sometimes hard to locate at vendors in the USA, RWS is popular among European competition shooters. The top-tier RWS ammo is a choice of many competitive shooters. RWS currently offers nine Premium Line .22 LR varieties and three Professional Line offerings. The SSUSA tester noted that RWS Rifle Match ammo shot great in his Bergara BMR, shooting one-ragged-hole groups at 50 yards and about one MOA at 100 yards. That’s great performance for $10/box ammo.
Norma .22 LR Ammunition
Norma recently introduced XTREME LR-22, a new type of competition rimfire ammo with a radical new bullet. This unique, patented bullet design has a special base with a cone (see diagram). Norma claims that this “rocket tail” design reduces drag by creating less negative pressure at the back end of the bullet. It will be interesting to see how this new bullet design works in rimfire ELR competition.
Wolf .22 LR Ammunition
SSUSA says that Wolf Match Target is a top performer in the under-$10 per box category. This is because, according to SSUSA: “It is manufactured by ELEY in England (and loaded with Vihtavuori powder) and re-branded, if online information is correct.” Wolf Match Target is available from Target Sports USA for $84.99 per thousand ($0.17 per round).
Aguila .22 LR Ammunition
Made in Mexico, Aguila .22 LR rimfire ammo is the bargain item among the seven ammo-makers featured by SSUSA. We wouldn’t choose Aguila for a benchrest or three-position match, but it could be more than adequate for a local NRL-22 match or a steel-target competition at relatively short range. Aguila .22 LR ammunition starts at under $3.00 per box.
Precision Benchrest and F-Class shooters favor premium brass from Lapua, Norma, Peterson, or RWS. (Lake City also makes quality brass in military calibers.) Premium brass delivers better accuracy, more consistent velocities, and longer life. Shooters understand the importance of good brass, but many of us have no idea how cartridge cases are actually made. Here’s how it’s done.
The process starts with a brass disk stamped from strips of metal. Then, through a series of stages, the brass is extruded or drawn into a cylindrical shape. In the extrusion process the brass is squeezed through a die under tremendous pressure. This is repeated two or three times typically. In the more traditional “draw” process, the case is progressively stretched longer, in 3 to 5 stages, using a series of high-pressure rams forcing the brass into a form die. While extrusion may be more common today, RWS, which makes some of the most uniform brass in the world, still uses the draw process: “It starts with cup drawing after the bands have been punched out. RWS cases are drawn in three ‘stages’ and after each draw they are annealed, pickled, rinsed and subjected to further quality improvement measures. This achieves specific hardening of the brass cases and increases their resistance to extraordinary stresses.” FYI, Lapua also uses a traditional draw process to manufacture most of its cartridge brass (although Lapua employs some proprietary steps that are different from RWS’s methods).
After the cases are extruded or drawn to max length, the cases are trimmed and the neck/shoulder are formed. Then the extractor groove (on rimless cases) is formed or machined, and the primer pocket is created in the base. One way to form the primer pocket is to use a hardened steel plug called a “bunter”. In the photos below you see the stages for forming a 20mm cannon case (courtesy OldAmmo.com), along with bunters used for Lake City rifle brass. This illustrates the draw process (as opposed to extrusion). The process of draw-forming rifle brass is that same as for this 20mm shell, just on a smaller scale.
River Valley Ordnance explains: “When a case is being made, it is drawn to its final draw length, with the diameter being slightly smaller than needed. At this point in its life, the head of the draw is slightly rounded, and there are no provisions for a primer. So the final drawn cases are trimmed to length, then run into the head bunter. A punch, ground to the intended contours for the inside of the case, pushes the draw into a cylindrical die and holds it in place while another punch rams into the case from the other end, mashing the bottom flat. That secondary ram holds the headstamp bunter punch.
The headstamp bunter punch has a protrusion on the end to make the primer pocket, and has raised lettering around the face to form the headstamp writing. This is, of course, all a mirror image of the finished case head. Small cases, such as 5.56×45, can be headed with a single strike. Larger cases, like 7.62×51 and 50 BMG, need to be struck once to form a dent for the primer pocket, then a second strike to finish the pocket, flatten the head, and imprint the writing. This second strike works the brass to harden it so it will support the pressure of firing.”
Thanks to Guy Hildebrand, of the Cartridge Collectors’ Exchange, OldAmmo.com, for providing this 20mm Draw Set photo. Bunter photo from River Valley Ordnance.
When we first ran this story a while back, it generated great interest among readers. By popular request, we’re reprinting this story, in case you missed it the first time around. — Editor
Precision Benchrest and F-Class shooters favor premium brass from Lapua, Norma, Peterson, or RWS. (Lake City also makes quality brass in military calibers.) Premium brass delivers better accuracy, more consistent velocities, and longer life. Shooters understand the importance of good brass, but many of us have no idea how cartridge cases are actually made. Here’s how it’s done.
The process starts with a brass disk stamped from strips of metal. Then, through a series of stages, the brass is extruded or drawn into a cylindrical shape. In the extrusion process the brass is squeezed through a die under tremendous pressure. This is repeated two or three times typically. In the more traditional “draw” process, the case is progressively stretched longer, in 3 to 5 stages, using a series of high-pressure rams forcing the brass into a form die. While extrusion may be more common today, RWS, which makes some of the most uniform brass in the world, still uses the draw process: “It starts with cup drawing after the bands have been punched out. RWS cases are drawn in three ‘stages’ and after each draw they are annealed, pickled, rinsed and subjected to further quality improvement measures. This achieves specific hardening of the brass cases and increases their resistance to extraordinary stresses.” FYI, Lapua also uses a traditional draw process to manufacture most of its cartridge brass (although Lapua employs some proprietary steps that are different from RWS’s methods).
After the cases are extruded or drawn to max length, the cases are trimmed and the neck/shoulder are formed. Then the extractor groove (on rimless cases) is formed or machined, and the primer pocket is created in the base. One way to form the primer pocket is to use a hardened steel plug called a “bunter”. In the photos below you see the stages for forming a 20mm cannon case (courtesy OldAmmo.com), along with bunters used for Lake City rifle brass. This illustrates the draw process (as opposed to extrusion). The process of draw-forming rifle brass is that same as for this 20mm shell, just on a smaller scale.
River Valley Ordnance explains: “When a case is being made, it is drawn to its final draw length, with the diameter being slightly smaller than needed. At this point in its life, the head of the draw is slightly rounded, and there are no provisions for a primer. So the final drawn cases are trimmed to length, then run into the head bunter. A punch, ground to the intended contours for the inside of the case, pushes the draw into a cylindrical die and holds it in place while another punch rams into the case from the other end, mashing the bottom flat. That secondary ram holds the headstamp bunter punch.
The headstamp bunter punch has a protrusion on the end to make the primer pocket, and has raised lettering around the face to form the headstamp writing. This is, of course, all a mirror image of the finished case head. Small cases, such as 5.56×45, can be headed with a single strike. Larger cases, like 7.62×51 and 50 BMG, need to be struck once to form a dent for the primer pocket, then a second strike to finish the pocket, flatten the head, and imprint the writing. This second strike works the brass to harden it so it will support the pressure of firing.”
Thanks to Guy Hildebrand, of the Cartridge Collectors’ Exchange, OldAmmo.com, for providing this 20mm Draw Set photo. Bunter photo from River Valley Ordnance.
Even with high-quality brass from Lapua, Norma, and RWS, occasionally you may find one or two cases per box which have a small flake or obstruction in the flash-hole. This will appear like a thin crescent on one side of the flash hole (see photo). You should inspect ALL new brass before loading to identify any pieces with a partially-obstructed flash hole. It’s a good idea to remove any flake or thin crescent left as an artifact of the flash-hole forming process. Because the flash-hole itself is normally centered and of the correct diameter, it is not necessary to ream the flash-hole to a larger diameter. All you really need to do is remove the small obstruction(s). This can be done quickly with inexpensive tools.
Use a Small Pin Vise to Remove Flash-Hole Obstructions
Folks have asked if there is a tool that can remove obstructions from a Lapua small, BR-sized flash hole without opening the hole size. The Lapua PPC/BR flash hole is spec’d at 1.5mm, which works out to 0.059055″. Most of the PPC/BR flash-hole uniforming tools on the market use a 1/16″ bit which is nominally 0.0625″, but these often run oversize — up to 0.066″.
If you want to just clear out any obstructions in the flash hole, without increasing the flash hole diameter, you can use an inexpensive “pin vise” with an appropriate drill bit. For $0.99, eHobbyTools.com sells a 1.5mm drill bit, item 79186, that matches the Lapua flash hole exactly. Other vendors offer a #53 pin vise drill bit that measures .0595″ or .060″ (depending or source). An 0.0595″ bit is close enough. You can find pin vises and these small-diameter drill bits at hobby stores.
For quite some time, Sinclair Int’l has sold a similar device for small (PPC and BR-size) flash holes. Like the 07-3081 unit for large flash holes, the 073000 Reamer for small flash holes works from the outside, so it can index off the primer pocket. It reams to .0625″, and also costs $39.99. The standard dimension for Lapua 220 Russian and 6mmBR flash holes is 1.5mm or .0590″. This tool will permit standard-size decapping rods with .0625″ tips to work without binding. However, note that both Forster and Redding normally supply .057″ decapping pins with their PPC and BR dies. So, it is NOT necessary to ream your Lapua BR/PPC flashholes, unless you prefer to do so for uniformity. It IS, however, a good idea to check BR/PPC flash holes for burrs before loading the first time.
NOTE: If you purchase either the 073081 or 073000 Sinclair Flash Hole Reamer tools, we recommend you mic the cutter tip before you process a bunch of cases. Sometimes a tip comes through that is oversize. This will ream the flash holes larger than you may intend.
When we first ran this story a while back, it generated great interest among readers. By popular request, we’re reprinting this story, in case you missed it the first time around. — Editor
Precision shooters favor premium brass from Lapua, Norma, or RWS. (Lake City also makes quality brass in military calibers.) Premium brass delivers better accuracy, more consistent velocities, and longer life. Shooters understand the importance of good brass, but many of us have no idea how cartridge cases are actually made. Here’s how it’s done.
The process starts with a brass disk stamped from strips of metal. Then, through a series of stages, the brass is extruded or drawn into a cylindrical shape. In the extrusion process the brass is squeezed through a die under tremendous pressure. This is repeated two or three times typically. In the more traditional “draw” process, the case is progressively stretched longer, in 3 to 5 stages, using a series of high-pressure rams forcing the brass into a form die. While extrusion may be more common today, RWS, which makes some of the most uniform brass in the world, still uses the draw process: “It starts with cup drawing after the bands have been punched out. RWS cases are drawn in three ‘stages’ and after each draw they are annealed, pickled, rinsed and subjected to further quality improvement measures. This achieves specific hardening of the brass cases and increases their resistance to extraordinary stresses.” FYI, Lapua also uses a traditional draw process to manufacture most of its cartridge brass (although Lapua employs some proprietary steps that are different from RWS’s methods).
After the cases are extruded or drawn to max length, the cases are trimmed and the neck/shoulder are formed. Then the extractor groove (on rimless cases) is formed or machined, and the primer pocket is created in the base. One way to form the primer pocket is to use a hardened steel plug called a “bunter”. In the photos below you see the stages for forming a 20mm cannon case (courtesy OldAmmo.com), along with bunters used for Lake City rifle brass. This illustrates the draw process (as opposed to extrusion). The process of draw-forming rifle brass is that same as for this 20mm shell, just on a smaller scale.
River Valley Ordnance explains: “When a case is being made, it is drawn to its final draw length, with the diameter being slightly smaller than needed. At this point in its life, the head of the draw is slightly rounded, and there are no provisions for a primer. So the final drawn cases are trimmed to length, then run into the head bunter. A punch, ground to the intended contours for the inside of the case, pushes the draw into a cylindrical die and holds it in place while another punch rams into the case from the other end, mashing the bottom flat. That secondary ram holds the headstamp bunter punch.
The headstamp bunter punch has a protrusion on the end to make the primer pocket, and has raised lettering around the face to form the headstamp writing. This is, of course, all a mirror image of the finished case head. Small cases, such as 5.56×45, can be headed with a single strike. Larger cases, like 7.62×51 and 50 BMG, need to be struck once to form a dent for the primer pocket, then a second strike to finish the pocket, flatten the head, and imprint the writing. This second strike works the brass to harden it so it will support the pressure of firing.”
Thanks to Guy Hildebrand, of the Cartridge Collectors’ Exchange, OldAmmo.com, for providing this 20mm Draw Set photo. Bunter photo from River Valley Ordnance.
Low-BC bullets launched from a .22 LR gun are easily blown around by the wind. That’s why it’s a smallbore shooter’s dream to shoot indoors, where fickle wind currents are less likely to spoil your shots. Not many folks have the opportunity to shoot indoors at all, must less compete in an indoor match. However, a crew from Ashbury Precision Ordnance recently got the chance to try out their rimfire rifles in a indoor setting, a converted poultry barn to be precise. And today they’ll be competing in a smallbore “Barn Benchrest” match at that same barn. Looks like fun!
Could this be the beginning of a new “Barn Benchrest” league? The folks at Ashbury tell us: “Rube, Gary, and Matt headed over the mountains to Luray, Virginia, to get in some practice for [Saturday’s] .22 Cal Benchrest Rifle Match. It’s colder than a well diggers’ butt outdoors, but shooting a match indoors, in a converted poultry barn, is nice. As always, we’re shooting great RUAG/RWS ammo!”
Poultry Barn aka Piney Hill Benchrest Facility
The official name of this converted barn is the Piney Hill Benchrest facility. Virginia State 3-Gun Rimfire BR Championships will be held there February 20-21, 2015, while the IR50/50 Indoor Sporter Nationals are scheduled for Piney Hill in March. If you’re curious, the benches are made from cement blocks with wood tops, so they’re very solid. Here’s a panorama photo of the Piney Hill Barn.
When we first ran this story a while back, it generated great interest among readers. By popular request, we’re reprinting this story, in case you missed it the first time around. — Editor
Precision shooters favor premium brass from Lapua, Norma, or RWS. (Lake City also makes quality brass in military calibers.) Premium brass delivers better accuracy, more consistent velocities, and longer life. Shooters understand the importance of good brass, but many of us have no idea how cartridge cases are actually made. Here’s how it’s done.
The process starts with a brass disk stamped from strips of metal. Then, through a series of stages, the brass is extruded or drawn into a cylindrical shape. In the extrusion process the brass is squeezed through a die under tremendous pressure. This is repeated two or three times typically. In the more traditional “draw” process, the case is progressively stretched longer, in 3 to 5 stages, using a series of high-pressure rams forcing the brass into a form die. While extrusion may be more common today, RWS, which makes some of the most uniform brass in the world, still uses the draw process: “It starts with cup drawing after the bands have been punched out. RWS cases are drawn in three ‘stages’ and after each draw they are annealed, pickled, rinsed and subjected to further quality improvement measures. This achieves specific hardening of the brass cases and increases their resistance to extraordinary stresses.” FYI, Lapua also uses a traditional draw process to manufacture most of its cartridge brass (although Lapua employs some proprietary steps that are different from RWS’s methods).
After the cases are extruded or drawn to max length, the cases are trimmed and the neck/shoulder are formed. Then the extractor groove (on rimless cases) is formed or machined, and the primer pocket is created in the base. One way to form the primer pocket is to use a hardened steel plug called a “bunter”. In the photos below you see the stages for forming a 20mm cannon case (courtesy OldAmmo.com), along with bunters used for Lake City rifle brass. This illustrates the draw process (as opposed to extrusion). The process of draw-forming rifle brass is that same as for this 20mm shell, just on a smaller scale.
River Valley Ordnance explains: “When a case is being made, it is drawn to its final draw length, with the diameter being slightly smaller than needed. At this point in its life, the head of the draw is slightly rounded, and there are no provisions for a primer. So the final drawn cases are trimmed to length, then run into the head bunter. A punch, ground to the intended contours for the inside of the case, pushes the draw into a cylindrical die and holds it in place while another punch rams into the case from the other end, mashing the bottom flat. That secondary ram holds the headstamp bunter punch.
The headstamp bunter punch has a protrusion on the end to make the primer pocket, and has raised lettering around the face to form the headstamp writing. This is, of course, all a mirror image of the finished case head. Small cases, such as 5.56×45, can be headed with a single strike. Larger cases, like 7.62×51 and 50 BMG, need to be struck once to form a dent for the primer pocket, then a second strike to finish the pocket, flatten the head, and imprint the writing. This second strike works the brass to harden it so it will support the pressure of firing.”
Thanks to Guy Hildebrand, of the Cartridge Collectors’ Exchange, OldAmmo.com, for providing this 20mm Draw Set photo. Bunter photo from River Valley Ordnance.
Precision Benchrest and F-Class shooters favor premium brass from Lapua, Norma, Peterson, or RWS. (Lake City also makes quality brass in military calibers.) Premium brass delivers better accuracy, more consistent velocities, and longer life. Shooters understand the importance of good brass, but many of us have no idea how cartridge cases are actually made. Here’s how it’s done.
The headstamp bunter punch has a protrusion on the end to make the primer pocket, and has raised lettering around the face to form the headstamp writing. This is, of course, all a mirror image of the finished case head. Small cases, such as 5.56×45, can be headed with a single strike. Larger cases, like 7.62×51 and 50 BMG, need to be struck once to form a dent for the primer pocket, then a second strike to finish the pocket, flatten the head, and imprint the writing. This second strike works the brass to harden it so it will support the pressure of firing.”
Precision Benchrest and F-Class shooters favor premium brass from 
The headstamp bunter punch has a protrusion on the end to make the primer pocket, and has raised lettering around the face to form the headstamp writing. This is, of course, all a mirror image of the finished case head. Small cases, such as 5.56×45, can be headed with a single strike. Larger cases, like 7.62×51 and 50 BMG, need to be struck once to form a dent for the primer pocket, then a second strike to finish the pocket, flatten the head, and imprint the writing. This second strike works the brass to harden it so it will support the pressure of firing.”
