April 16th, 2016

Helpful Advice on Case Trimming from PMA Tool

Eric Cortina Trimmer
The Giraud power trimmer indexes off the shoulder of the case. It is costly, but offers high production rates, trimming to length and chamfering in one operation.

The folks at PMA Tool, makers of arbor presses, neck-turning tools, and other case-prep tools, offer some good advice about case trimming on the PMA Tool Blog. Here we reprint a PMA blog post that explains case trimming basics and helps you choose the right case-trimming tool for your needs.

Case Trimming Basics
Trimming the cartridge case to the proper length is a crucial step in case preparation that should not be overlooked or underestimated. The cartridge case or the rifle can be damaged, or even worse you get badly injured. In most instances cases should be trimmed after firing and sizing. Trimming new brass is necessary for a lot of wildcats and can be beneficial in some instances, but by and large, trimming new brass is not necessary for most situations (unless you are neck-turning). Cases should be trimmed after you have sized the case, because the expander ball on the decapping pin can (and will) stretch the neck. Those of us who neck size should get into the habit of trimming after sizing as well. This is a good rule of thumb to go by, and hopefully it will keep you safe during the reloading and shooting process.

There are so many case trimmers out there that work, deciding which one is right for you can be confusing. Even though I have trimmed thousands of cases, using about every method possible, I can’t answer the question of what case trimmer is right for you because of all the variables that may be involved. I can, however shed some light on the subject.

Wilson Micrometer Case Trimmer

The two most popular designs of trimmers either index (1) off the base or the head of the case, (2) off the shoulder or datum line of the case. There are pros and cons to each and it all depends on what you are willing to live with.

Indexing off the Base (Case Head)
Let’s talk about the first one I have listed, indexing off the base, or the head of the case. The pros to this method are that you can achieve a very accurate over all length and that is after all, what it is all about. The cons to this method are that you can get some variation doing it this way. Let me explain, the base is not always square to the body or can be damaged during firing especially if it is fired through a military style rifle with a very aggressive ejector. These cases should be discarded, but sometimes they can be overlooked. This condition can lead to an over all length that is incorrect. The case head being out of square will be corrected upon firing, however that case will wind up being shorter than the rest of your cases, possibly creating a difference in the neck tension on the bullet. The more you can do to eliminate variables in your reloads the better off you are going to be. This method can also be very slow, and if the user gets careless the result will be a inconsistent over all length.

Forster Case Trimmer

Indexing off the Shoulder (Datum Line)
The second method I mentioned, trimming off the shoulder or the datum line of the case, has its pros as well. I have found this to be the quickest of the methods and very accurate as well. After the case has been sized through the die the dimensions (particularly the headspace) of the cases are usually very uniform and exact, this allows the case to be trimmed by indexing off the shoulder. This method can be done very quickly, by hand, or by powering either the case, or the trimmer. You also don’t have to worry about the case heads being out of square with the body using this method. Generally the trimming time is cut in half, and this leads to greater focus on the job, without becoming careless.

PMA tool case trimming trimmer micro-adjust

The PMA Micro-Adjust Case Trimmer indexes case length off of the shoulder of a properly fire-formed and full-length re-sized case. We accomplish this through the use of interchangeable Delrin™ inserts which capture the shoulder and neck of the case. This insert is contained in a spring-loaded tool head that rides on a linear bearing. When the case is captured within the tool head the tool head rotates along with the case, the spring allows for the case to self-align squarely to the cutter and allows you to control the feed rate into the cutter.

— Indexes off shoulder for easy, consistent trim length
— Fully rotating head with bearing for smooth operation keeps cuts square
— Large, ergonomic design fits the hand well
— Sharp carbide cutter for quick, smooth cuts with minimal bur
— Cases captured in Delrin™ (completely non-marring material)
— Spring loaded head allows complete control of rate of feed.

Our trimmer can be used in three ways. The first method utilizes our PMA Tool caseholder drivers and your power screwdriver, drill, case lathe, drill press or lathe. Trimming via this method the case is spun and fed into the trimmer while it is held in your hand. In the second method, the trimmer’s adjustment knob is removed (after adjusting and locking the setting) and the cutting shaft is chucked in a drill, drill press or lathe. Using this method, the case itself is held by hand and fed into the cutter. We’ve found this to be the quickest method to trim.

Summary
The choice is yours to make. I hope that this was some help to you, whether you are looking for your first trimmer or looking to replace the trimmer you have. Just remember to always put safety first and accuracy second, and you will start making little bug holes in no time.

Story Tip by EdLongrange. User Submissions are welcome.
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April 16th, 2016

Rio’s Remarkable Olympic Shooting Center

Shooting Competition Rio Brazil 2016 Shooting Center

The 2016 Summer Olympic Games will be held in Rio de Janeiro, Brazil. Marksmanship will be an important part of the Rio Olympics. Nearly 400 top shooters from around the world will compete in rifle, pistol, and shotgun events. The shooting competitions will take place in a large, modern sports complex originally created for the 2007 Pan-American Games at a cost of $53.5 million. This complex, located within the Deodoro Olympic Park in Rio, offers roughly 30,000 square meters of improved areas on the 125,000 square meter site. Brazil’s Olympic Shooting Center (also known as the National Shooting Center) is an impressive facility. In size, scale, cost, and capabilities, Rio’s Shooting Center is without rival in the Southern Hemisphere.

Video Showcases Brazil’s Modern Olympic Shooting Center:

Visit RIO 2016 Olympics Shooting Webpage

ISSF World Cup Underway at Shooting Center Now
If you want to learn more about the Olympic Shooting Center in Rio, there is an good article on the Shooting Sports USA website. This covers the history of Brazil’s Olympic shooting teams, and explains what competitors can expect this summer. Right now the Olympic Shooting Center is being used for the ISSF World Cup.

2016 Olympic Dress Rehearsal
“The 2016 Olympic Games this August will be one of the largest sporting events ever held. There will be another contest this year in the wonderful city of Rio de Janeiro that will function as a ‘dress rehearsal’ for the big show. On April 14-25, the Olympic Shooting Center will host the International Shooting Sport Federation (ISSF) World Cup. During the 11-day competition, 700 athletes from dozens of countries will showcase their skills at the biggest shooting sport event in Brazil before the Olympics.” — Read more at Shooting Sports USA

Shooting Competition Rio Brazil 2016 Shooting Center

Shooting Competition Rio Brazil 2016 Shooting Center

Shooting Center Photos from video by BCMF Arquitetos.

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April 16th, 2016

Eastern CMP Games and Creedmoor Cup Coming Soon

Eastern CMP Games and Creedmoor Cup

The 10th Annual Eastern CMP Games and Creedmoor Cup Matches will be held at Camp Butner, North Carolina, April 29 through May 8, 2015. The Eastern CMP Games run April 29 through May 3, while the Creedmoor Cup Matches will follow the Eastern Games, May 4-8. Events will include a 4-Man Team Match, Creedmoor Cup Match and EIC Match. All interested shooters are invited to participate in this popular event, which includes: Rimfire Sporter Match, M16 Match, M1 Garand Match, Springfield Match, M1-Carbine Match, Vintage Military Match, Modern Military Match, Vintage Sniper Match, Pistol Matches and more.

Eastern CMP Games and Creedmoor Cup

There will also be skills training seesions throughout the week, including a High Power Shooting Clinic, Pistol Clinic, and GSM New Shooter Clinic. The free Team Remington High Power Shooting Clinic will offer instruction by some of the nation’s top High Power service rifle competitors. This will feature lectures, dry fire training, plus lots of hands-on coaching with a large squad of instructors. The Eastern CMP Games will also conduct a Small Arms Firing School (SAFS). The SAFS instruction is geared toward new shooters, so no previous firearm experience is required.

CMP Games Information Page | CMP Games Registration Page | CMP Games Entry Form.

Eastern CMP Games and Creedmoor Cup
The Vintage Sniper Match is a two-person team match, utilizing scoped rifles from the Korean War, World War II or earlier, upon sandbags. Teammates take turns as both shooter and spotter.

Garand-Springfield-Military New Shooter Clinic
The Garand-Springfield-Military (GSM) New Shooter Clinic is recommended for all new shooters to the CMP Games, as well as those who may not be firing, but simply would like to learn more about the events. The clinic includes classroom instruction, demonstrations and dry-fire position practice – all led by CMP GSM Master Instructors.

Great Place to Get Started in Competitive Shooting
The CMP Games matches are ideal events for shooters who have not participated in previous competitions. Shooters are permitted to coach or assist each other in these matches. Experienced shooters are encouraged to assist new shooters with positions, slings, loading and the rules.

Eastern CMP Games and Creedmoor Cup

To learn more about the Eastern CMP Games, email croguski [at] thecmp.org or call (888) 267-0796, extension 714. If you have questions about the Creedmoor Cup contact Dennis DeMille, demille [at] creedmoorsports.com or call (800) 273-3366 M-F, 9:00 am – 6:00 pm Central Time.

Eastern CMP Games and Creedmoor Cup

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