Bullet Comparators: A Comprehensive Guide (Updated August 2023)

Understanding Bullet Comparators: The Foundation of Precision Reloading

If you've ever wondered why some shooters consistently achieve tighter groups than others despite using similar equipment, the answer often lies in the details of their ammunition. For reloaders, one of the most critical yet frequently overlooked tools is the humble bullet comparator.

A bullet comparator is a precision measuring tool that allows reloaders to measure cartridge length from the case head to the bullet's ogive (the curved portion of the bullet) rather than to its tip. While this might seem like a minor distinction, it's actually a game-changer for achieving consistent, accurate ammunition.

Here's why ogive measurement matters: Bullets with the same overall length (OAL) but different shapes can have vastly different distances from base to ogive. This means they'll interact differently with the rifling in your barrel, leading to inconsistent pressure and accuracy issues.

The science behind this is straightforward. According to a study by Precision Shooting Magazine, variations in bullet seating depth as small as 0.005 inches can change muzzle velocity by up to 50 feet per second and significantly impact point of impact, especially at longer ranges.

"The difference between average shooting and exceptional accuracy often comes down to consistency in ammunition preparation," explains Mike Turner, a competitive shooter with over 20 years of experience. "And you simply can't achieve that consistency without measuring from the ogive."

Traditional calipers can only measure to the bullet tip, which is problematic because:

• Soft point and polymer-tipped bullets have variable tip lengths
• Slight damage to bullet tips changes measurements without affecting performance
• The ogive, not the tip, is what engages with the rifling

This is where a quality bullet comparator like the AltitudeCraft kit comes in, providing the ability to make consistent, meaningful measurements that directly translate to better accuracy on the range.

The Problem with Traditional Measurement: Why Your Calipers Aren't Enough

I've seen plenty of reloaders making the same mistake—measuring cartridge overall length (COAL) using just a standard caliper. At first glance, this seems reasonable. After all, isn't the total length what matters? But there's a fundamental flaw in this approach that's costing shooters both accuracy and consistency.

The issue is that bullet tips are notoriously inconsistent, even within the same box from premium manufacturers. According to testing by the National Rifle Association, variations in bullet tip length within the same box can be as much as 0.015 inches—enough to cause noticeable point-of-impact shifts at just 100 yards.

Consider these real-world problems faced by reloaders:

• Soft-point hunting bullets can have tip variations of up to 0.020 inches within the same box
• Polymer-tipped bullets may have consistent tips but varying ogive profiles
• Bullet tips can be damaged during handling without affecting ballistic performance
• Different bullet designs with identical overall lengths can have significantly different ogive positions

As Amazon reviewer Scott T. notes, "Measuring to ogive to assure seating consistency is the only way to really get the accuracy you're chasing. Soft point bullets and tipped bullets vary in length by enough to throw you off if you only use OAL."

Another critical issue is that without ogive measurement, you can't accurately determine bullet jump—the distance a bullet travels before engaging the rifling. This jump directly affects pressure, velocity, and accuracy. Too much jump causes inconsistency; too little can create dangerous pressure spikes.

This problem is compounded when working with different bullet types in the same caliber. A hollow point, soft point, and FMJ bullet might all measure the same overall length, but have dramatically different ogive positions—leading to completely different performance characteristics.

The AltitudeCraft Solution: Precision Engineered for Reloaders

The AltitudeCraft Bullet Comparator Kit directly addresses the measurement challenges that plague reloaders with an elegantly designed system offering both versatility and precision. At its core, this kit is about eliminating variables and providing consistent, reliable measurements that translate to better performance on the range.

What sets the AltitudeCraft kit apart is its comprehensive approach. With 14 different caliber inserts ranging from .17 to .45, this single kit covers virtually every caliber a reloader might work with. Each insert is precisely machined from 6061 aluminum with tolerances maintained within 0.003-0.005 inches of specified dimensions.

The product's clever design solves several common issues:

• The ceramic-like hard anodic finish prevents wear and tear that could affect measurement accuracy over time
• Color-coded inserts allow for quick identification and reduce the chance of using the wrong size
• The included storage tin with custom foam inserts keeps all components organized and protected
• The universal design fits virtually any standard caliper, removing the need for specialized equipment

According to ballistics expert David Tubb, "Consistency in bullet seating depth relative to the lands is one of the most critical factors in achieving optimal accuracy." The AltitudeCraft kit makes achieving this consistency not just possible, but straightforward.

The real magic happens when you use this tool to develop loads tailored specifically to your firearm. By measuring from the case head to the ogive, you gain the ability to precisely control bullet jump—the distance the bullet travels before engaging the rifling. This level of control allows reloaders to find the optimal seating depth for their specific rifle and ammunition combination.

Data from the Precision Rifle Blog indicates that finding the optimal bullet jump can reduce group sizes by up to 50% in many rifles. With the AltitudeCraft kit, you have the precision tool needed to experiment with and optimize this critical variable.

Comparator Kit Alternatives: How They Stack Up

When shopping for a bullet comparator, you'll encounter several options from established brands like Hornady, RCBS, and Sinclair, as well as budget alternatives. Understanding how these compare to the AltitudeCraft kit is essential for making an informed decision.

The primary advantage of the AltitudeCraft kit is its comprehensive inclusion of 14 inserts covering the full spectrum from .17 to .45 caliber. As one reviewer noted, "This set is great for its price while offering a large range of calibers for the majority of your reloading needs."

Hornady's offering is perhaps the most direct competitor, but it comes with fewer inserts in the base package and lacks the convenient storage solution. As reviewer H.J. Seeley pointed out, "I had to get a new set of comparators because I keep losing my Hornady inserts. This set is really nice because of that box that keeps everything organized in one place."

RCBS and Sinclair options generally focus on fewer calibers but are constructed of steel rather than aluminum. While steel may offer marginally better durability, the anodized aluminum of the AltitudeCraft kit provides more than adequate durability for typical use while remaining lightweight.

Where budget options fall short is typically in manufacturing precision and consistency. Some cheaper alternatives can have significant variance in hole dimensions, which defeats the purpose of a precision measuring tool.

Interestingly, one reviewer who performed detailed measurements found the AltitudeCraft inserts to be "between about 0.007" and 0.009" under nominal bullet diameter," which is appropriate for the intended function and comparable to more expensive alternatives.

Key Features Breakdown: What Makes This Comparator Kit Stand Out

The AltitudeCraft Bullet Comparator Kit isn't just another measuring tool—it's a thoughtfully engineered reloading accessory with features that directly address the needs of serious reloaders. Let's examine the key components and what makes them valuable.

1. Comprehensive Insert Collection

With 14 caliber-specific inserts, this kit covers an exceptionally wide range of bullet diameters:

• .172 (for 17 Remington, 17 Hornet)
• .204 (for 204 Ruger)
• .224 (for 223 Rem, 5.56 NATO, 22-250)
• .243 (for 243 Win, 6mm)
• .257 (for 25-06, 257 Roberts)
• .264 (for 6.5 Creedmoor, 260 Rem)
• .277 (for 270 Win)
• .284 (for 7mm Mag, 7mm-08)
• .308 (for 308 Win, 30-06, 300 Win Mag)
• .338 (for 338 Lapua, 338 Win Mag)
• .358 (for 35 Whelen, 350 Legend)
• .375 (for 375 H&H, 375 Ruger)
• .416 (for 416 Rigby, 416 Rem Mag)
• .458 (for 45-70 Gov't, 458 Win Mag)

This breadth ensures you won't need to purchase additional components regardless of which calibers you reload. As one reviewer noted, "They covered all calibers. Use them all the time."

2. Dual-Screw Mounting System

The comparator body features two brass thumbscrews that secure it to your caliper. This design provides more stable and secure attachment than single-screw alternatives, resulting in more consistent measurements. The thumbscrews can be operated without tools, making field adjustments simple.

3. Color-Coded Identification System

Each insert is anodized in a different color according to its caliber group, making identification quick and intuitive. This thoughtful touch eliminates the frustration of squinting at tiny markings and reduces the chance of using the incorrect insert.

4. Metal Storage Tin with Custom Foam Insert

Unlike many competitors that provide minimal packaging, the AltitudeCraft kit includes a durable metal storage tin with custom-cut foam inserts. This keeps all components organized and protected when not in use. Multiple reviewers specifically mentioned appreciating this feature, with one stating, "The design is dead nuts simple and it comes in a nice metal storage box with foam cut-outs to keep things in place."

5. High-Quality Anodized Aluminum Construction

The 6061 aluminum construction provides an excellent balance of durability and weight. The ceramic-like hard anodic finish prevents wear that could affect measurement accuracy over time, while keeping the tool lightweight and easy to handle.

Real-World Benefits for Shooters: Why Precision Matters

The technical features of the AltitudeCraft Bullet Comparator Kit translate into tangible benefits for different types of shooters. Let's explore how this precision measurement tool makes a real difference in various shooting disciplines.

For Long-Range Precision Shooters

Long-range precision shooting magnifies even tiny inconsistencies. A variation of just 0.005" in bullet seating depth can shift point of impact by several inches at 1,000 yards. The benefits for these shooters include:

• Ability to fine-tune bullet jump for optimal accuracy in their specific rifle
• Consistency across reloading batches, ensuring predictable performance
• Reduced vertical dispersion in shot groups, leading to tighter groups overall
• Data collection capabilities to identify optimal loads for different conditions

According to the Precision Rifle Blog, "The difference between mediocre and exceptional long-range performance often comes down to the fine details of ammunition preparation, with bullet seating depth being among the most critical variables."

For Hunters

Hunters benefit from the confidence that comes with knowing their ammunition will perform consistently when it matters most:

• More predictable point of impact at varying distances
• Improved accuracy for ethical harvesting of game
• Ability to develop loads optimized for hunting bullets, which often have soft or polymer tips that can vary in length
• Consistent performance across temperature ranges typically encountered in hunting conditions

For Competitive Shooters

In competitive shooting, where fractions of an inch can separate winners from losers, the benefits are clear:

• Elimination of variables that can affect shot-to-shot consistency
• Ability to replicate successful loads with precision
• Reduced flyers and more predictable performance under pressure
• Confidence in equipment, allowing focus on technique

Even for casual shooters, the enhanced accuracy and consistency translate to a more rewarding range experience with tighter groups and improved confidence in their handloaded ammunition.

As reviewer Rsscully notes, "My measurements are much more consistent and I feel better about my repeatability on the finished product."

How to Use a Bullet Comparator: A Step-by-Step Guide

Getting the most out of your bullet comparator requires proper technique. Here's a straightforward guide to using the AltitudeCraft Bullet Comparator Kit effectively.

Setting Up Your Comparator

1. Select the appropriate insert for your bullet caliber from the 14 provided options.
2. Insert it fully into the comparator body, ensuring it seats completely and securely.
3. Attach the comparator body to your caliper using the two thumbscrews. Position it so that the insert aligns with the measuring surfaces of the caliper.
4. Zero your caliper with the comparator attached to ensure accurate measurements.

Measuring Loaded Ammunition

1. Place the base of the cartridge against the fixed jaw of your caliper.
2. Slide the bullet into the comparator insert attached to the moving jaw until the ogive contacts the insert.
3. Read the measurement displayed on your caliper. This is the base-to-ogive length.
4. Record this measurement for future reference or comparison.

Finding Optimal Seating Depth

To determine the ideal seating depth for your rifle:

1. Create a dummy round with the bullet seated long enough that it will contact the rifling when chambered.
2. Carefully chamber this round and then extract it. The bullet will be pushed back into the case.
3. Measure this adjusted round with your comparator to find the exact length where the bullet contacts the rifling.
4. Seat your actual rounds slightly shorter than this measurement (typically 0.010"-0.020" shorter) to provide the optimal "jump" to the rifling.

Using for Quality Control

The comparator is also excellent for ensuring consistency across a batch of ammunition:

1. Measure several rounds from your batch.
2. Calculate the average length and note any variations.
3. Adjust your reloading process if variations exceed 0.003".
4. Periodically check factory ammunition to ensure consistency.

Remember that while the specific measurement itself isn't standardized across different comparators (as one reviewer notes, "a comparator is not an absolute"), what matters is consistency within your own setup. Your measurements are unique to your equipment and serve as your personal reference standard.

Customer Experiences: Real-World Feedback

The true test of any reloading tool comes from those who use it in the field and at the loading bench. The AltitudeCraft Bullet Comparator Kit has accumulated numerous reviews from verified purchasers, providing valuable insights into its real-world performance.

Consistent Praise for Organization

One recurring theme in customer reviews is appreciation for the storage solution. As reviewer Range Squirrel notes, "I chose this over the Hornady Headspace Comparator solely on the packaging. The design is dead nuts simple and it comes in a nice metal storage box with foam cut-outs to keep things in place."

Another purchaser, H.J. Seeley, shared: "This set is really nice because of that box that keeps everything organized in one place. It's such a great idea rather than Hornady's cheap blister pack."

Feedback on Accuracy and Performance

Regarding the crucial aspect of measurement accuracy, reviews are generally positive. Tampa Hoosier writes, "I am happy to report, the kit I received was every bit as accurate as my calipers. The comparator base with an attached caliber-specific bushing should be zeroed out at 1". When I assembled the 30 caliber bushing onto the base and attached it to the moving arm of my caliper it read 1.000."

Tswoodshop compared the kit to a name-brand alternative: "I compared this to my Hornady bullet comparator testing several calibers on various bullets, and it was dead on target."

Comments on Build Quality

The anodized aluminum construction receives mixed but generally positive reviews. One customer who did detailed inspection noted, "The inserts are all fall between about 0.007" and 0.009" under nominal bullet diameter. This is pretty much spot on for the calibers between .264 and .458 but it's a bit much for the smaller calibers."

Aaron Pasteris observed, "Inserts are aluminum so could wear with a LOT of use but you'd have to move up to Sinclair at 5x the cost to get stainless. So for the vast majority of reloaders this is a lifetime kit."

Customer Service Experiences

Several reviewers specifically mentioned positive experiences with AltitudeCraft's customer service. One customer who received a defective insert reported, "AltitudeCraft has responded with EXCELLENT customer support. Very eager to fix the issue, sent replacement at no cost."

Another reviewer, Shawn, noted: "1st set came in missing a piece, put in for a reorder and got it replaced no problem. Company communicated very well."

Making Your Decision: Is This Comparator Kit Right for You?

After exploring the features, benefits, and real-world feedback on the AltitudeCraft Bullet Comparator Kit, it's time to determine if this tool deserves a place in your reloading setup. Let's consider different scenarios and requirements to help you make an informed decision.

Who Should Definitely Get This Kit

This comparator kit is an excellent investment if you:

• Reload multiple calibers - With 14 inserts from .17 to .45, this single kit covers virtually all common calibers, eliminating the need to purchase multiple specialized kits.
• Value organization - If you're tired of losing small reloading components, the included metal storage tin with custom foam inserts will keep everything in one convenient place.
• Are pursuing maximum accuracy - For competitive shooters, long-range enthusiasts, or anyone looking to optimize their handloads for the highest possible precision.
• Are new to precision reloading - The comprehensive kit provides all the tools needed to begin measuring and controlling bullet seating depth, an essential skill for serious reloaders.

Potential Limitations to Consider

While the kit offers excellent value, there are some considerations:

• Aluminum vs. Steel - The aluminum construction is lighter but potentially less durable than steel alternatives. For most reloaders, this won't be an issue, but extremely high-volume users might prefer steel inserts.
• Marking Visibility - Several reviewers mentioned that the caliber markings on lighter-colored inserts can be difficult to read in certain lighting conditions.
• Insert Length for Large Calibers - One reviewer noted that when using very long bullets in larger calibers like .375 or .416, the bullet tip may protrude through the bushing and contact the caliper.

The Bottom Line: An Excellent Value Proposition

For the vast majority of reloaders, the AltitudeCraft Bullet Comparator Kit represents an excellent balance of functionality, convenience, and value. It provides professional-grade measurement capabilities at a price point that's accessible to hobbyists and serious shooters alike.

As reviewer Jeff B. succinctly put it: "For the price, it would be difficult to beat this bullet length comparator set... I don't know how you could do better. This bullet comparator set is a good value and I definitely recommend it."

If you've been measuring only to the bullet tip and wondering why your groups aren't as consistent as they could be, or if you're looking to take your reloading to the next level of precision, this comprehensive kit provides everything needed to start measuring what truly matters—the distance from case head to bullet ogive.

Frequently Asked Questions