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March 24th, 2021

Accuracy One Seating Depth Comparator Review

Accuracy One Seating Depth Comparator gauge ogive shoulder measure reloading ammunition case

Looking for a faster, easier, and more accurate way to measure bullet positions on your loaded rounds? Check out the Accuracy One Seating Depth Comparator. This unique tool provides a shoulder-to-ogive measurement instead of the traditional cartridge base-to-ogive measurement. The Accuracy One Comparator just might work for you. This unique tool allows a very rapid and secure measurement that provides a precise determination of the bullet seating depth in the case.

Accuracy One Seating Depth Comparator

Product Review by F-Class John
You probably check your loaded ammo by measuring cartridge base to ogive, but have you ever considered there may be a better way? Curt at Accuracy One has considered the question, and after exhaustive research and testing he created the Accuracy One Seating Depth Comparator. As opposed to looking for a base to ogive measurement, this tool measures from the shoulder to ogive, which is arguably the more repeatable number when it comes to accuracy.

Click Arrow to Watch Video Tool Review

As Curt explains, “Well, when you fire a chambered cartridge, the strike from the firing pin first pushes the cartridge forward until it bottoms against the shoulder. The primer is then ignited. What this means is that your seated bullet depth consistency can more accurately be gauged using the dimension from shoulder to ogive. Using this dimension, you effectively eliminate any small variances in your sized case length from the equation”. As a result, it made sense that when he was designing the measurement tool his goal was to create a universal insert that allowed a user a quick, easy, accurate and repeatable process that measures from mid-shoulder to ogive.

Accuracy One Seating Depth Comparator gauge ogive shoulder measure reloading ammunition case

The comparator fits cartridges from .22 to .30 Caliber with 0.400″ and larger shoulder diameters. The tool fits so many bullet sizes because of the specific taper that Curt developed. This ensures that any caliber in that range makes good contact along the ogive. As I used this tool and talked to people about it, I kept getting skeptical comments with people asking how it could measure the ogive on that many calibers accurately. I had to remind them that the ogive is not a single point on the bullet but in fact the entire curve from the tip of the bullet to the point it straightens out. As a result, it’s only important that the tool you use is consistent in what point along the ogive it measures and that’s where the Accuracy One Seating Depth Comparator shines. According to Curt, he went through countless iterations on his design until he was able to accurately and repeatably measure all those calibers (.22 to .30).

Accuracy One Seating Depth Comparator gauge ogive shoulder measure reloading ammunition case

How to Use the Accuracy One Seating Depth Comparator
Using the comparator is simple. There are alternative methods. The easiest way is to simply zero the indicator, insert a loaded round, note the measurement and compare any future rounds against it for variation. An alternative to this is a method I use. I insert a loaded round and then zero the indicator. This allows you to see the exact variation without mental math (and frankly it’s faster this way). I also use this method to sort loaded rounds for matches in order from shortest to longest ensuring that rounds that measure the same are fired together.

Bonus Option — Measuring Length to Lands with Tool
Another great use for this Accuracy One comparator is to take my initial depth to lands. This helps ensure my seating depth was properly set. Using a case with very light neck tension, I load a bullet, and with a stripped bolt I load and close it. Then I can remove the round and take a measurement, zero the indicator and make a note of it in my book. After that the comparator will remember the new zero until it’s zeroed again and if that happens by accident, I can always reference the number that my round measured and pull on the indicator stem until that number is found and then zero it again. I found this entire process fast, easy and repeatable as I loaded rounds and needed to check for any seating depth variance.

Tool Pricing:
Seating Depth Comparator without Indicator: $65.00
Seating Depth Comparator with Indicator: $115.00
Gauge Stand: $47.00

Accuracy One Seating Depth Comparator gauge ogive shoulder measure reloading ammunition casePurchase Options
You can buy the tool with or without an Digital Indicator. Accuracy One also makes a Primer Depth Gauge. Both Accuracy One tools employ the same digital indicator. This helps save money as you can order the comparator alone if you already have one (either from another Accuracy Tool or another tool).

The Accuracy One Seating Depth Comparator is essentially the same size as the Accuracy One Primer Depth Gauge, so you can even utilize Accuracy One’s primer gauge storage case. There is also an optional stand that I HIGHLY RECOMMEND as it can hold either the seating depth OR primer gauge, making for amazingly simple one-handed operation while you’re loading.

CONCLUSION — Tool Is Precise, Repeatable, and Fast
Overall, this tool left me feeling confident in my depth setting and I found it quick and easy compared to past methods. At the end of the day there are several ways to skin the proverbial cat when it comes to measuring seating depth. But if you’re looking for what just might be the most accurate, consistent and speediest method, give the Accuracy One Seating Depth Comparator a try.

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May 30th, 2018

New Accuracy One Precision Primer Gauge

Accuracy One Precision Primer Gauge prime seating depth crush thickness measuring primer pocket

For centerfire rounds, consistent ignition (and low ES/SD) all begins with the primer in the base of the cartridge. When the firing pin strikes the primer, it sets off a small flame/spark which lights the powder in the case. Energy from that burning powder pushes the bullet out of the cartridge, down the barrel, and out to the target. It’s fair to say, then, that accurate shooting all begins with the primer.

When seating primers, consistency counts. You want to make sure the primer is fully seated in the primer pocket in the base of the case. You want to ensure a slight bit of crush (flattening) for proper seating, and it doesn’t hurt to have very consistent primer seating depths. That’s why guys use tools to uniform their primer pockets.

Here’s a new tool that lets you measure the consistency of primer seating depths. We haven’t used this device yet, but Forum members have reported it works well — measurements are quick and repeatable. Will this tool lower your ES/SD or improve accuracy? That’s hard to say. However, it will definitely help you detect when a primer in a loaded round is seated too high or too low — that’s important. In addition, it can give you precise measurements for comparison testing with different types of primers.

Accuracy One Precision Primer Gauge

The Accuracy One Precision Primer Gauge will precisely measure primer pocket depth and the depth of seated primers in relationship to the face of the case head. The Precision Primer Gauge can also be used to measure the thickness of an unseated primer, allowing you to calculate the optimum seating depth for the particular primers and cases you are loading.

Accuracy One Precision Primer Gauge prime seating depth crush thickness measuring primer pocketPrecision Primer Gauge Features:

Digital Indicator with 0.01mm/0.0005″ resolution
Gauge Body is machined from 303 stainless steel
Small Primer Stem and Large Primer Stem
Both .223 Rem and .308 Win zeroing block
Magnum and .338 Lapua zeroing block

Case Compatibility: The Precision Primer Gauge works with 300 Win. Mag case head diameter (.532”) cartridges, .308 Win. case head diameter (.473”) cartridges, and .223 Rem case head diameter (.378”) cartridges using either large or small primers.

Precision Primer Gauge Pricing:

PPG Without Indicator: $100.00
PPG With Indicator: $150.00
PPG Main Body Only: $40.00
Phone Orders: Call (814) 684-5322

How to Order the Precision Primer Gauge:
The Precision Primer Gauge can be ordered via phone, or by sending in the PDF ORDER FORM form via mail or email.

Assembly Tips: Nylon screw is provided for securing the gauge body to the indicator. The contact point of the indicator must be removed to provide proper function. Also, please note that the standard gauge body is not compatible with cartridges that share the .338 Lapua case head diameter unless the diameter of the magnum step is machined to .595” to accept the larger diameter case head. This modification of the gauge body is available upon request.

Product Tip from EdLongRange. We welcome reader submissions.
Permalink Bullets, Brass, Ammo, New Product, Reloading 3 Comments »