February 9th, 2017

Nifties for Fifties — Cool Stuff for the .50 BMG

.50 50 BMG fifty caliber powder Reloder 50 Comparator brass trimmer

Alliant 50 BMG PowderAlliant’s Powder for 50-Caliber Applications
In 2009 Alliant unveiled Reloder 50, a new powder designed for long-range, 50-caliber rifle shooters. According to Alliant, the burn rate is “a little slower than Winchester 860″ and the powder is showing excellent lot-to-lot consistency. Load density is optimized for the 50 BMG and similar cases. Like Reloder 17, Reloder 50 employs a process which penetrates the kernels with the burn-rate-controlling chemical. This should allow a longer, flatter pressure curve, yielding more velocity than conventional powders can deliver. Alliant says that Reloder 50 offers “superior velocity and the ability to burn cleaner (with less residue).” Reloder 50 comes in both 1-lb (#150527) and 8-lb (#150528) containers.

Giraud 50 BMG Case/Bullet Comparator
Giraud Tool makes a comparator for 50-Cal cartridges. The double-ended comparator is quite versatile. In one orientation you can measure base-to-ogive bullet length and also measure cartridge OAL from rim to bullet ogive. When reversed, you can use the comparator to measure cartridge headspace. The $30.00 Giraud 50 BMG Comparator gauge is constructed of 303 stainless and fits most any vernier, dial, or digital caliper. CLICK HERE for more info.

Giraud Tools 50 BMG comparator gauge

Forster 50 BMG Trimmer
50 BMG enthusiasts asked for a dedicated 50 BMG case trimmer, so Forster created a trimmer specifically for that cartridge. Forster’s cutter tip is much sharper than the cutter on the Lyman 50 Cal. AccuTrimmer. However, with the Forster tool you will pay more for that superior cutting ability — Forster’s 50 BMG trimmer costs $95.99 at Sinclair International. Yes, Lyman also makes a dedicated 50 BMG Case trimmer ($66.49 at MidwayUSA), but the Forster cutter head is much sharper, and we prefer the Forsters collet-style case-holder. Bottom line — the Forster gets the job done more quickly, with less effort, so it’s worth the extra money.

Forster 50 BMG case Trimmer

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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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