Best Dial Caliper for Reloading

A Quick Guide for Selecting the Best Dial Caliper for Reloading!

Reloading ammunition demands precise measurements for consistent accuracy, function, as well as safety. The most versatile measuring instrument is a dial caliper that enables the reloader to accurately measure inside, outside, and depth. If you reload your own ammunition you should be using the best dial caliper for reloading for optimum results.

After decades in the machining business I have acquired an intimate familiarity with the concept of precision. Additionally, having used dial calibers almost on a daily basis for work and for precision reloading I have, what you might call a unique perspective as to what to look for when selecting a dial caliper for reloading.

In today’s market, there is an abundance of dial calipers to choose from. A quick search will reveal products priced from as low as $20 and as high as $120 or more. Thanks to CNC machining technology, even the cheapest models are capable of reasonably accurate measurements. However, there are other important issues that should be considered before purchasing a dial caliber for reloading.

What Are the Best Dial Calipers for Reloading?

RECOMMENDATIONS

To be able to offer you what I believe are the best recommendations I have combined my years of experience using dial calipers along with product specs, and customer feedback. Although this article focuses on Dial Calipers, I have taken the liberty to offer my recommendation for a Digital Caliper also.  Please keep in mind the important role this tool will play in your reloading ammo while making a selection.

BEST OVERALL:

Starrett R120A-6 Stainless Steel Dial Caliper

Range: 0-6” inches

Accuracy: +/- 0.001″

Resolution: .001″

Measurements: Outside, Inside, Step, and Depth

Includes: Plastic Case

Overview

Founded in 1880, Starrett is the pinnacle of USA measuring instrument manufactures. Their tools are widely used by engineers, toolmakers, precision machinists and anywhere precise reliable and accurate measurements are necessary.

Coveted Quality

With its distinct red face, the Starrett Dial Caliper 3202-6 is the tool every aspiring toolmaker or precision machinist covets.  Just having it on your workbench speaks volumes about its owner.  It is designed to provide precise inside/outside, step, and depth measurements up to 6 inches.  And, it is built to last a lifetime with proper use and care.

The Starrett Dial Caliper 3202-6 is crafted from 400 Series Stainless Steel and then tempered for maximum strength and wear resistance.  Each piece is CNC Machined and then ground to very tight tolerances. The jaw contact area is precision ground to almost a knife edge that enables you to easily measure narrow groves or slots.

The numbers and hash lines on the dial are vivid and easy to read. Each hash line and graduation number on the satin-finished bar is distinct black and easy to see at a quick glance.

Distinguishing Characteristics

One of the most distinguishing characteristics of this precision built-tool is its smoothness of operation. The fine adjustment roll is knurled for non-slip use with the thumb.

A critically important feature of the Starrett Dial Caliper 3202-6 is the Positive Split Gear Anti-backlash Control. What this amounts to is a spring-loaded pinion gear that eliminates any clearance between the mated gears. This assures that once the instrument is calibrated it will provide accurate outside and inside measurements. (SEE:  How to Calibrate a Dial Caliper)

I have been using Starrett measuring tools for all of my adult life and I can tell you with confidence they are simply the best. The Starrett Dial Caliper 3202-6 is an outstanding choice for precision reloading ammunition because it will withstand the high volume of use without failing.

It is on the pricy side but it represents an investment that will keep on paying dividends for a lifetime. It’s the only dial caliper actually Made in America.

MOST PRACTICAL:

Hornady #050075 Dial Caliper Stainless Steel, 6″

Range: .000 to 6.0” inches

Accuracy: +/- 0.001″

Resolution: .001″

Measurements: Outside, Inside, Step, and Depth

Includes: Protective Storage Case

Overview

As shooters we take pride in our equipment and often plaster company logos on our rifle cases or range bags. The HORNADY logo is perhaps the most familiar when it comes to ammo and reloading equipment. In addition to their line of high quality tools and accessories for reloading, Hornady has a ballistics laboratory where they have developed the world’s largest library of ballistics data. This company understands the unique relationship between precision and accuracy – In order to produce highly accurate reloaded ammunition, consistent precision must be maintained in the reloading process.

Manufactured to Precise Specifications

The Hornady #050075 Dial Caliper was designed by Hornady specifically for the reloader who expects repeatable accuracy when assembling ammo components. These calipers are manufactured in Asia to precise specifications and strict quality controls to assure the consistent quality you expect from Hornady.

Heat-treated 400 Series Stainless Steel is used for the frame and body. Each part is surface ground to close tolerances and the contact measuring surfaces are micro lapped to exact parallelism and squareness. This means when you open the caliper to 1.000” for example, both the inside and outside jaws are exactly one inch apart.

Premium Features

One of the features of the Hornady #050075 that stands out to me is the machined housing, vs cast. In my opinion, it makes for a stronger and better overall quality measuring instrument. This is a feature typically only found on higher-priced industrial grade calipers. The Hornady RED bezel really stands out and is easy for the eye to keep track of on the reloading bench.

The dial face is white with contrasting black numbers and hash lines with a fine point needle that provides vivid resolution. A knurled thumb screw is located at the bottom of the dial body to secure the bezel and maintain calibration. There is a knurled floating Thumb Friction Wheel that allows you to open or close the jaws and feel when the jaws come into contact with an object. A larger knurled thumb screw is located on the top of the body that locks the movable jaw in place when a measurement is taken.

Black hash lines and numbers are clearly laser-etched in the beam and graduated in .100 and Inch increments. The Depth Rod is machined to a narrow end that enables you to take precise depth measurements in tight places.

Trusted for Precision Machining and Reloading

The Hornady #050075 utilizes a spring-loaded anti-backlash design that keep the rack and pinion gear teeth meshed throughout the entire 6” measuring range. This arrangement eliminates any looseness as wear gradually develops over the years so the caliper will always provide accurate measurements at any point of the measuring range.

As a precision machinist I can’t compromise when it comes to measuring instruments. I must have tools I can trust or I end up losing the trust of my customers. The Hornady #050075 Dial Caliper is a measuring tool that can be trusted for precision machining as well as precision reloading.

 

BEST VALUE:

Fowler 52-008-706-0 Stainless Steel Dial Caliper

Range: 0-6” inches

Accuracy: +/- 0.001″

Resolution: .001″

Measurements: Outside, Inside, Step, and Depth

Includes: Plastic Storage Case

Overview

Headquartered in Newton, MA Fowler is an American manufacturing company that has been making precision measuring tools since 1946. This tool is imported and made to precise specifications.

Although I don’t currently own a Fowler dial caliper I do have many of their other measuring tools that have provided reliable service over the years.

The Fowler 52-008-706-0 is a machinist grade dial caliper with emphasis on rugged construction and precision accuracy for everyday use. It features Shockproof design and a high contrast dial face with graduations of 0.001” and +/- 0.001” accuracy. Easily measure outside, inside, or depths with the smooth sliding jaw. The Rack is protected with a shroud to prevent debris from getting in the teeth. A knurled Lock holds the jaw securely in place after taking a measurement. The thumb-operated fine adjustment wheel enables one hand operation.

Self-contained movement

Each of the main components is made from hardened stainless steel to provide corrosion resistance, accuracy, and long life. The movement is self-contained and designed to eliminate gear misalignment. A dual pinion drive mechanism greatly reduces any premature wear on the rack and pinion.

A spring Anti-backlash control prevents erratic readings as a result of any looseness between the rack and pinion gear teeth. This important feature prevents the gear from jumping out of sync which would cause false a measurement reading.

The dial is easily adjusted to a zero setting and a small knurled screw locks the bezel in place to prevent accidental movement once calibrated (SEE: How to Calibrate a Dial Caliper).

Whether you are a professional machinist, or a serious shooter who does reloads ammo, you can’t go wrong with the Fowler 52-008-706-0. It includes a plastic storage case and comes with Fowler’s 1 year warranty just in case something does go wrong. This is one of the best dial calipers currently available for precision reloading.

BEST MODERATELY PRICED:

RCBS 87305 Stainless Steel Dial Caliper

Range: 0-6” inches

Accuracy: +/- 0.001″

Resolution: .001″

Measurements: Outside, Inside, Step, and Depth

Includes: Fitted Plastic Case

Overview

If you are a shooter who is into reloading ammunition, chances are you have some RCBS products on your bench. RCBS has an established reputation for offering high quality reloading tools and accessories and their 87035 Dial Caliper is no exception.

This dial caliper is made from hardened stainless steel with a non-glare Matte finish that really helps see the hash marks on the beam. With this dial caliper you will be able to measure outside, inside, depth and steps accurately to plus or minus 0.001” of an inch. The movement is Shock Proof so you won’t have to worry about it losing accuracy with normal bumps and heavy handling.

Backlash-Eliminating Design

Slide locking is provided by a Knurled Thumb Screw. A small lock screw securely holds the dial in place after zeroing and calibration. (SEE: How to Calibrate a Dial Caliper) The Pinion gear is spring loaded to keep it in mesh with the rack teeth to eliminate backlash.

The quality and design of the RCBS 87305 Stainless Steel Dial Caliper is good and will serve every measuring need for reloading. In my opinion this dial caliper is somewhat better than similar priced models because the main body is machined vs cast. This makes it just a little more rugged and expensive but it also makes for a better quality tool that should last a lifetime with proper care.

BEST BUDGET-PRICED:

Accusize Industrial Tools P920-S236 Precision Stainless Steel Dial Caliper

Range: 0″ to 6″ inches

Accuracy: +/- 0.001″ and +/- 0.020mm

Resolution: .001″ and .020mm

Measurements: Outside, Inside, Step, and Depth

Includes: Fitted Plastic Case

Overview

Accusize Industrial Tool is a very large manufacture of precision measuring tools, cutting tools, and support tooling for the metalworking industry. They are a Canadian based distributor and source their tools from Canada, Asia, and the U.S.

As a very small machine shop operator, it is necessary for me to keep a tight rein on my expenses. I prefer to purchase all U.S.A. made tools but sometimes I have to go with a more affordable import to be able to turn a profit. I own about 6 Accursize Industrial Tool products that I use regularly and each one is top quality.

The Accusize Industrial Tools P920-S236 Dial Caliper is a high quality measuring instrument. It’s made from 400 Series hardened Stainless Steel with all surfaces ground to size. The measuring surfaces are micro lapped to assure precise measuring just like the much more expensive models. What that means is the Jaw measuring surfaces are exactly parallel with each other and flat unlike most of the economy-priced products. The housing is machined from solid bar stock instead of cast which makes it more rugged in my opinion.

Unique Feature

One of the unique features of this Dial Caliper is it provides measurements in both INCH and MILLIMETERS which comes in handy, especially in the machining trade. The dial has two needles that are independently geared with the shorter red needle to show MM and the longer black needle to show Inch. The Numbers and hash lines are very fine but also very vivid so you can clearly see them at a glance.

The dial face provides direct readings in 0.001” and 0.02mm on the large dial scale. When proper technique is used you can rely on this dial caliper to provide measurements accurate to within +/- 0.001 and +/- 0.020mm.

Smooth Operation

One of the things that impressed me about this Dial Caliper is how smooth the movement is with no looseness which is common with many of the cheap imports. This is an indication of holding close tolerances in the machining processes which takes more time. The floating fine adjustment wheel allows you to gauge the pressure when you are measuring an object. A small knurled head locking screw is located on the bottom of the instrument where it’s out of the way. A larger knurled head locking thumb screw is located on top and aft of the dial where it’s easily accessible.

AIT utilizes a spring-loaded anti-backlash pinion gear to prevent the gear from jumping out of sync with the rack. It also prevents any looseness between the gear teeth and the rack teeth to assure precise outside measurements when the instrument is calibrated for inside measurements. It simply means there is no need to perform separate calibrations for outside and inside measurements. (SEE: How to Calibrate a Dial Caliper)

If I was in need of a new dial caliper and on a tight budget (which I am lol), I wouldn’t hesitate to purchase the Accusize Industrial Tools P920-S236. I believe it’s the best budget-priced dial caliper currently available.

BEST DIGITAL CALIPER for RELOADING:

Mitutoyo 500-196-30 Absolute Scale Digital Caliper

Range: 0-6” inches

Accuracy: +/- 0.001” and +/- 0.02mm

Resolution: 0.0005″/0.01mm

Measurements: Outside, Inside, Step, and Depth

Includes: Protective plastic case and SR44 silver oxide battery

Overview

If you have decided that a Digital Caliper is a better option for reloading I strongly feel the Mitutoyo 500-196-30 Absolute Scale Digital Caliper is the best choice. I have used various digital caliper brands and models and can tell you from my own experience they are great when they work and a frustrating waste of time and money when they don’t.

If you are going to go the digital caliper route, don’t go cheap! The cheap models that are so plentiful have inferior electronics that are vulnerable to humidity and any bumps or jars typically encountered in a work environment. They go through batteries quickly and won’t last!

The Mitutoyo 500-196-30 is the latest generation of digital calipers that utilizes Absolute Encounter technology. Once it is set, it keeps track of its origin point so that whenever you turn it on the Display shows the actual position. This means that as soon as you turn the instrument on its ready to measure. This eliminates the need to repeatedly ZERO it each time you go to use it which is a great time saver.

Large LED Display and Easy Operation

One of the features you will appreciate is the large, easy-to-read LCD Display readout. Like most digital calipers the Mitutoyo 500-196-30 measures both in INCHES and MILLIMETERS by using the menu button. A Thumb Friction Wheel enables you to feel when the jaws make contact with an object for consistently precise measurements. And, you don’t have to worry about the dirt, oil, or moisture getting into the electronics with the sealed Advanced Onsite Sensor (AOS).

The Mitutoyo 500-196-30 Digital Dial Caliper has a long record of surviving day to day use in machine shops and industrial environments. It will easily survive the usual wear and tear typically encountered with volume reloading. It is pricy but considering the quality, features, and long life expectancy it is an investment you will appreciate every time you use it.

What to Look for When Choosing a Dial Caliper for Reloading!

Over the course of even a short reloading session a dial caliber will get used dozens of times. A serious rifle marksman who regularly shoots bench rest or precision long range competitions may load 200 or more rounds per session. Someone who is into pistol shooting competitions may load thousands of rounds per month. The point is that if you are paying attention to the multiple cartridge dimensions like you should a dial caliber will receive a lot of use.

Consequently, every time you move the caliper jaw back and forth it can eventually causes wear on the movable jaw and frame. The tiny little gear and the rack that it runs back and forth on can also become worn with high usage. Moreover, no lubricant should be used on any of the moving parts which can further accelerate wear. Accordingly, construction materials must be compatible in order to prevent premature wear. This design consideration adds significantly to the overall price of a good quality dial caliper.

Construction Materials

A top quality caliper frame and jaw should be machined from hardened 400 series stainless steel which is very resistant to wear. The rack should be made of C93600 to C93700 Bronze Alloy for maximum wear resistance. Additionally, the gear should be made from high carbon steel that has been heat treated for maximum wear resistance.

Readability

Another important feature to consider when selecting a dial caliper is the dial and the graduations on the frame. The Dial should have contrasting numbers and distinct hash marks for easy reading. Each hash mark on the slide should be precision laser etched and easy to read. The bezel should be free from excessive slop and yet easy enough to rotate for calibration. It should be equipped with an easy to access locking screw to assure it maintains calibration.

Function

One of the most important features to look for is ease of operation.  The caliper should have a smooth feel to it when sliding the movable jaw.  This is an important consideration to enable you to achieve consistent readings when taking a measurements.  Additionally, its one of the main distinguishing difference between an economy-priced dial caliper and a top of the line model.

A knurled clamping screw should be large enough to easily turn with your thumb and finger. This feature is to enable you to lock the caliper in place once you have taken a measurement.

Make sure the rack has a shroud to help shield it from dirt or debris becoming embedded in the teeth. If this happens it could cause the gear to jump a tooth and throw the instrument way out of calibration. Even with a shroud, care should be exercised to keep the caliper clean. I recommend that you develop the habit of laying your dial caliper face down when it’s not in use. Than minimizes the chance of debris getting into the mechanism.

QUICK TIP:  If you feel the slightest hesitation when you slide the caliper jaw you should stop immediately. Slowly reverse direction of the jaw to expose the rack and grab a can of Keyboard Spray Dust Cleaner.  Now, carefully blast any obstruction to safely remove it from the caliper rack. If you can still feel any hesitations use a toothbrush to loosen the offending debris and then give it a blast.

Which is Better – Dial Caliper vs Digital Caliper?

You may be wondering what are the advantages of a digital caliper vs a dial caliper. Both styles are very popular among serious reloaders and both have advantages and disadvantages that should be considered.

To offer some perspective I own and use both dial and digital calipers for my reloading and machining work. Consequently I have made some observations that may be helpful in making a decision that’s right for you.

Dial Caliper

Pros

• As a matter of habit I tend to favor using my dial calipers (I own 6). They are plenty accurate enough for reloading and they are reliable.
• With a dial caliper you don’t have to worry about any battery going dead just when you need them.
• Dial calipers tend to be more rugged than digital and less prone to failure.  They are less susceptible to shock from bumps or heavy handling.

Cons

• As I mentioned above, debris can become embedded in the rack teeth causing the gear to skip a tooth which will through the instrument out of calibration.
• Calibrating a dial caliper is just slightly more time-consuming than with a digital set. SEE: How to Calibrate a Dial Caliber

Digital Caliper

Pros

• I enjoy using a good quality digital caliper because tend to have a smoother feel than a dial caliper. The reason for this is digital calipers have an electric reader that scans the graduations on a scale without touching it as the jaw is moved back and forth. Whereas, a dial caliper utilizes a rack and gear to turn the dial hand that gives it a very slight mechanical feel.
• Reading a measurement on a LED Screen is easier than looking at a dial plus the slide scale on a dial caliper.
• Most Digital Calipers have both Fractional and Metric functions making it more versatile than a dial caliper. This feature doesn’t provide as much value for an ammo reloader as it does for a machinist.
• Digital calipers are extremely easy to calibrate with just a touch of the Reset button. Because of their enclosed design they are less vulnerable to dirt and debris affecting the calibration.

Cons

• Like any other battery-powered electronic instrument, digital calipers can become inoperative just when you need them. Changing out a battery is easy but just make sure you keep one or more handy because without a battery your nice digital calipers are useless.
• If you forget to check the battery now and then it can leak and damage the electronics beyond repair. A good habit to get into is removing the battery after each reloading session.

A good quality digital caliper is comparatively expensive.

Bottom Line

Both Dial and Digital calipers are highly accurate measuring instruments and either one works great for reloading ammunition.

Also SEE: How to Determine Correct Scope Ring Height

How to Calibrate a Dial Caliber

There are a couple ways to calibrate your dial calibers. The best way is to first wipe the stationary and movable jaws with your finger to remove any trace of dirt or lint. Then, close the jaws applying light pressure and at the same time adjust the bezel so the -0- lines up with the hand.

Some of the more expensive dial calibers come with a 1.000” standard that should be used to check the calibration. If you do have a standard it’s better to use that to set the dial. You should make sure that you get a 1.000 reading on the standard and then check with the jaws closed to make certain it reads zero. If not, you might not be applying equal pressure for both readings.

I highly advise that you check the calibration frequently and before starting each reloading session.