Posts Tagged ‘5.56 NATO’

Essential Gear: Using the L.E. Wilson Rifle Case Gage

Friday, September 11th, 2015

There are certain tools that can save you a lot of time, effort, and money. For reloaders of ammunition, a case gage is one such tool. Have you ever gone to the range and discovered an issue with your handloads? I certainly have. While a case gage can’t prevent all ammunition problems, it is what I would call “cheap insurance”. If you properly use a case gage, you can be have confidence that your ammunition will chamber properly, and feed reliably (for magazine fed firearms).

L.E. Wilson Case Gage Dial Indicator Full-2000

I have recently upgraded to L.E. Wilson case gages for all of the cartridges that I load (with the exception of 7.62x54R which L.E. Wilson doesn’t make a case gage for). I had a bad experience with a 308 Winchester sizing die setup on one of my progressive presses and ended up with some batches of bad ammunition. From now on, using a case gage is “mandatory process” for every press setup I perform. There are plenty of options for case gages, but I use L.E. Wilson because their products are top quality, they are a family run business, and they are “local”: just 4 miles from the “Ultimate Reloader Outpost”. The information in this article will be in reference to the L.E. Wilson bottleneck rifle case gage, although most of the principles will apply to other brands and types of case gages. I’ll use 308 Winchester as the “example cartridge” here, but note that the concepts apply to most other bottleneck rifle cartridges. Gages like this are used to verify your sizing die setup, and to verify trim-to length for your brass.

Before talking about how to use this type of case gage to verify sizing die setup, it’s important to understand the concept of “headspace”. There are various classes of rifle and pistol cartridges that have their own concept of headspacing (bottleneck rifle, belted magnum rifle, traditional semi-auto pistol, rimmed revolver cartridges, …). Headspace is a measurement that determines what the cartridge “stops against” when chambered, and any corresponding dimensions/tolerances. In the case of bottleneck rifle cartridges this dimension is between a “datum line” on the shoulder on the front side, and the bolt face on the back side. The datum line corresponds to a portion of the shoulder on the case of known diameter.

Headspace is a measurement that determines what the cartridge “stops against” when chambered, and any corresponding dimensions/tolerances.

The diagram below shows the headspace measurement for 308 Winchester:

308 Winchester Headspace Diagram

The case gage measures case overall length based on the shoulder, a function of headspace dimensions – Image copyright 2015 Ultimate Reloader

From the SAAMI 308 Cartridge Dimensions Page, the headspace dimensions are as follows:

  • Datum shoulder diameter: .400″
  • Headspace length: 1.634″ -.007″ (1.627″ – 1.634″)

When checking to see if your cartridge will properly chamber, the case gage is checking the “datum to head” length between the case shoulder and the case rim. The nice thing about this type of gage is that you don’t have to have special tools that are used with calipers- you just drop in the case/cartridge and check min/max indicators on the gage compared with the depth of the case/cartridge. It’s fast and easy.

L.E. Wilson Case Gage Scene Full-2000

After gaging my “bad batch” of 308 Winchester, I noticed that these previously machine gun-fired cases had neck bulging. A further examination of my reloading press setup revealed that while the sizing die appeared to be “bottomed out” – flex in the press sub-plate resulted in a not-deep-enough sizing die condition. Here’s the before and after shot showing what the brass looked like:


While I could have found this by visual examination, using a case gage would have made this issue instantly apparent and obvious. Lessons learned! I have since decided that for super-duty sizing operations (like this military 7.62x51mm brass) I’m going to size on a single stage press first, then prime/charge/seat on a progressive press. Hopefully that will yield reliable and consistent results. If you are full-length sizing brass on a progressive press, be sure to check your sized brass carefully both while sizing a case (only case in press) during setup, and while performing full-progressive loading with cases in all stations.

Using the L.E. Wilson case gage to validate sizer die setup is simple- you size a case, then drop it in (case mouth first) into the large opening on the case gage. There are two surfaces on the top of the gage:

  • The upper surface: corresponds to max length
  • The stepped-down lower surface: corresponds to minimum length

If the case rim for the case/cartridge your are checking protrudes above the max length surface, there’s no gurantee your completed cartridge will chamber. If the case rim falls below the minimum surface, the case shoulder will not be tight in the chamber which is bad for accuracy. Furthermore, if the shoulder moves forward more than ~.005″ when the cartridge is fired, the case head could separate- and that’s not good at all!

L.E. Wilson Case Gage Dial Indicator Indicating Rim-2000

In the picture above, you can see the dial indicator reads – 0.005″ indicating off the case rim, which means it’s flush with the lower step, which means it’s in-spec.

There are a few different ways you can perform this measurement:

  1. Use a straight edge – scraping over the upper surface, should clear the case rim. Scraping over the lower surface should “skim” or catch on the case rim
  2. Use a dial indicator on a stand (shown in the pictures in this article, and demonstrated in the video below)
  3. Use a depth micrometer
  4. Use dial or digital calipers

Note: if you use the dial indicator method to measure headspace length, you need to make sure the case mouth does not protrude out the bottom of the case gage or sit flush. This will cause a faulty measurement/indication. If this is a possibility it is best to position the case gage over a suitable recess or hole to prevent such a condition.

If you use the reference surfaces on the case gage, you’ll be assured that your ammunition should chamber in any “in-spec” firearm of the proper chambering. But what if you want optimized sizing for precision and accuracy for ammunition intended for a single (non semi-auto) firearm? If that’s your desire, you can use the method recommended by L.E. Wilson:

  1. Drop a previously fired case into the gage (ensure there are no dings or nicks, case mouth not bent/collapsed)
  2. Take a depth reading of the case rim relative to the upper surface of the case gage
  3. Subtract .002″ – .004″ (depends on how tight you want cartridge to chamber)
  4. Use the adjusted depth measurement to evaluate and fine-tune your sizer setup

As mentioned previously, the case gage can also be used to measure the trim-length of the brass you are working with. To perform this measurement, drop a case into the gage, flip it over, and set the gage on a flat surface as shown below:

L.E. Wilson Case Gage Case Length Measurement-2000

Reading the measurement is simple, just check that the case mouth length falls between the lower surface and upper surface of this end of the gage. Very fast and easy to use! By checking sizing die setup and case trim length, you’ll be confident that your ammunition will perform optimally from a performance/accuracy perspective, and will also chamber and feed reliably.

It’s also important to understand that final sized brass dimensions are a function of the pre-sized brass dimensions, case wall thickness, sizer die setup, and other factors. This concept is important, because the result is that different batches of brass will size to different final dimensions due to the “spring-back” effect. You push back the shoulder with a sizing die, and the shoulder “springs back” a few thousandths of an inch (but will vary based on the factors described previously). If you are particular about precision and accuracy, you should sort your brass into “groups” and then validate sizing die setup for each group of brass that you process.

Sorting criteria for groups of brass can be simplified to:

  • Cases that are over max headspace
  • Cases that are  at or close to max headspace
  • Cases that are close to min headspace

This way you can be certain of your results.

Here’s a video demonstrating how the L.E. Wilson case gage is used to validate 308 Winchester sizing die setup and trim-to length:

You can find L.E. Wilson gages on various online retailer’s websites, or go directly to L.E. Wilson.

Happy [confident] loading to you all! Stay tuned here because I’ll be following-up with an article and video covering L.E. Wilson pistol gages.


6.5mm Grendel: 308 Ballistics for the AR-15

Friday, September 4th, 2015


When Steve Lawrence from the 6.5 Guys asked if I’d like to shoot his AR-15 chambered in 6.5mm Grendel, I said: “Absolutely!”. We were up at the “Ultimate Reloader Outpost” working on another shooting project, and had some spare time. A great opportunity to try a new AR-15 chambering!

Prior to to this experience, I knew little about the 6.5mm Grendel cartridge, and had no idea why it was developed. Steve explained that this cartridge enables an AR shooter to achieve similar ballistics to 308 Winchester from a 6.5 mm cartridge that can be utilized by rifles built on the AR-15 platform. Since the AR-15 is more compact and lighter in weight, an AR-15 in 6.5mm Grendel is an interesting alternative to the AR-10/LR308 type platforms.

When I first picked up a 6.5mm Grendel cartridge, I thought- “Wow, that’s short and compact”. It’s actually derived from the 7.62x39mm cartridge, another popular chambering for the AR-15. By necking down the 7.62x39mm to 6.5mm, more velocity is attained from a similar powder charge.


Designed in 2003, he 6.5mm Grendel is a relatively new cartridge. The “short and compact” form factor is the result of the need for more powder capacity (compared with 5.56 NATO or .223 Remington) and to allow “room” for long slender high-BC bullet profiles. At the same time, the cartridge needs to fit into AR-15 length magazines. It’s a game of trade-offs, but the 6.5mm Grendel manages these trade-offs very well.

Here are the dimensions for the 6.5mm Grendel cartridge, from the cartridge diagrams page on


And here you can see the ballistically-similar 308 Winchester cartridge along side the 6.5mm Grendel. Different designs, different proportions, different bullet diameters, but similar trajectory. You may also notice here how Steve’s Lapua brass looks much nicer than my 7.62x51mm military brass.


Steve’s rifle means serious business. It features a 26 inch barrel, a huge muzzle brake, a two-stage trigger, and a Bushell HDMR scope held in place by a LaRue SPR quick-attach scope mount.

Here I am holding Steve’s rifle:


It’s interesting to handle rifles, examine cartridges, and to study specifications and ballistics. But the real story unfolds when you pick up the rifle and see what it (and the shooter) can do. Steve had a bunch of loaded rounds that he needed to shoot as a part of his brass preparation process, so I got to empty several magazines through the rifle. This was enough shooting to get some good mirage through the scope from the air passing over the hot barrel.

Here’s a quick video that shows me shooting Steve’s awesome rifle:

I did have one flier (first shot), but I managed to put 4 successive rounds into about 1/2″ at 100 yards at a pace of 3-4 seconds between shots. Get rid of the flier, and I’d be really happy with that.


Steve has spent quite a bit of time perfecting his loads for this cartridge and rifle. The load we were shooting is as follows:

  • Bullet: Hornady 123 grain AMAX
  • Federal small rifle match primer
  • 27.9 grains IMR 8208 XBR (Hodgdon lists 28.5 grains as max)
  • Lapua 6.5mm Grendel brass

Note: This load data is for reference only. Always cross-reference with manufacturer’s load data. Ultimate Reloader is not responsible for errors or possible issues you may have when using this load data. Use at your own risk.

Steve noted that for some reason, IMR 8208 XBR is used pretty much across the board by competitive shooters shooting 6.5mm Grendel- it seems to be just the right formulation for this unique cartridge and the peculiarities of the AR-15 platform.

It was a lot of fun to experience the 6.5mm Grendel, and I’m really impressed with Steve’s rifle and loads. It’s not hard to see why people like this cartridge. If you want to read more, check out these resources:


Cleaning Reloading Dies with an Ultrasonic Cleaner

Monday, August 3rd, 2015

Disgusting. That’s the word I use to describe my crusty jar of mineral spirits that I use to clean dies. It’s a mess to use, and when I blow dry the dies there’s a fine mist of mineral spirits that you can smell in the shop air. You may know the feeling: the excitement of unboxing dies, and the realization that you’ll need to spend 15-20 minutes cleaning them until they are “de-gunked” of the factory oil and ready to use in your press. I’ll admit, I’ve used dies without cleaning them, and while it may not cause many problems, at minimum they can coat your fingers with oil each time you touch them. It’s not satisfying to use dies that have gummed up factory oil on them: I don’t even like the look of oiled-up dies on my presses. For me, it’s time to turn the page- I’m hoping I’ve found a better way to keep my dies clean. We’ll see!


After getting a new RCBS ultrasonic cleaner, I thought I should give that a try instead of my old crusty jar. RCBS has both “Weapons Cleaning Solution” (intended for guns and gun parts) and “Case Cleaning Solution” (intended for brass). Since reloading dies are pretty much like gun parts, I thought I would give the Weapons Cleaning Solution a try. The RCBS Weapons Cleaning Solution comes in a 32 fluid oz. container that has a handy built-in measuring/dispensing chamber. The instructions state that you should use a minimum of 40 parts water to 1 part cleaning solution, up to a maximum of 14 parts water to 1 part cleaning solution. I chose a middle value of 30 parts water to 1 part solution when I mixed the batch used for this article and video.

RCBS Weapons Cleaner

Here’s the video, which shows the setup, cleaning cycle, and drying procedure that I used to clean some brand new RCBS 45 ACP dies:

Here’s how the parts came out of the cleaner (after some drying time):

RCBS Dies Drying

After the parts were completely dry, they felt clean, and according to RCBS they now have a protective film of corrosion protection. Thankfully, this film of protection is not something that’s apparent when you handle the parts. That would defeat the purpose of cleaning new dies wouldn’t it?

I think I’ll go and clean my first batch of brass with this Ultrasonic Cleaner!

Talk to you all soon,

Unboxing the RCBS Ultrasonic Cleaner

Thursday, July 30th, 2015

In preparation for loading 45 ACP on the RCBS Pro Chucker 5, I thought it would be a great idea to “get serious” about my die cleaning setup. Well, I’m about to show you a huge upgrade from my “shake the dies in a can of paint thinner method” that I’ve used for years. I’m pretty excited to “step into the modern era” on this one.


Enter the RCBS Ultrasonic Cleaner. This unit is packed with features, and will be great for cleaning dies, cleaning handguns and gun parts, and cleaning brass. In this post/video, I’ll do a live un-boxing (no, I didn’t peek inside prior to shooting the video :)).

Here’s the overview of what’s included:



  • Main unit
  • Parts basket
  • Power cord
  • Drain hose
  • Owner’s manual

I’m looking forward to cleaning some dies with this unit- that’s up next. I’ll pick up where we left off here with setup, and we’ll get those 45 ACP dies ready to rock on the RCBS Pro Chucker 5!



RCBS Pro Chucker 5: Press Assembly Part 2

Saturday, July 11th, 2015

In this post, I’ll continue where we left of in my last post (see RCBS Pro Chucker 5 Press Assembly Part 1) by taking on the assembly of the new-and-improved RCBS Uniflow powder measure. This new version of the Uniflow that’s included with the Pro Chucker 5 features some great updates that include a quick-change metering insert system, and a “universal drum” that’s used for both rifle metering inserts and pistol metering inserts.

Here’s what the new Uniflow powder measure looks like installed on the press:

RCBS Pro Chucker 5 Powder Measure Assembled 500

In the video below, I’ll show the process of assembling the powder measure from the parts and sub-assemblies that come with the press as pictured here:

RCBS Pro Chucker 5 Powder Measure Parts 1200

You can watch here:

Now that we’ve unpacked, mounted, and assembled the press, I think it’s time to start cranking out some ammo! Stay tuned for the next post and video which will cover loading 45 ACP. Can’t wait!