TESTED: Starline 6mm Creedmoor Brass (Large and Small Primer)

Starline brass has performed really well for me, and 6mm Creedmoor is no exception! I’ve spent quite a while loading and shooting 6mm Creedmoor Starline brass with both large and small primer pockets, and in this article I’ll share both my first hand experiences AND a bunch of lab data quantifying the consistency and performance for this brass.


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Starline 6mm Creedmoor Brass

Starline 6mm Creedmoor brass is available with conventional large primer pockets:

And also with small primer pockets:

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Lab Consistency Testing

For lab testes, 10 pieces of large rifle primer Starline 6mm Creedmoor brass were put through a variety of tests. Following this, 10 pieces of small rifle primer Starline 6mm Creedmoor brass were also tested for weight consistency  (the only test where I tested both, but I have shot both extensively).

Length Consistency

10 cases were measured for length with digital calipers accurate to 0.0005″. Here are the results:

Case Neck Thickness and Uniformity

Case neck thickness uniformity was tested by taking three neck thickness measurements with a ball micrometer accurate to 0.0001″. Here’s that data:

Case Capacity and Consistency

Five once-fired cases were tested for case capacity by using the H2O method (filling case to point where water is level at case mouth). One new case was tested for comparison:

Case Weight Consistency

This time I compared 10 cases with with large primer pockets with 10 cases that have small primer pockets. I thought perhaps there would be more mass in the small primer pocket brass. I used an A&D FX-120i lab scale accurate to 0.02 grains. Here’s the data!

So much for that theory! The weights were VERY close, with the large primer pocket brass coming in at about 0.3 grains HEAVIER. I’ll have to figure out why that’s the case!

My Custom 6mm Creedmoor Rifle

The rifle I’m developing loads for is my HOWA 1500 that I recently rebuilt to address some accuracy issues. I’m now able to attain approximately 1/4 MOA performance when things (including my shooting) are “dialed in”.

Here are some of the stories related to this rifle published so far:

Accuracy and Performance

For handloads, I’ve only used Starline 6mm Creedmoor brass, and here is where I landed!

For the load used in testing, I settled on the following components:

Here’s the video showing my load development process

These loads have produced great accuracy!

What’s more, I’ve seen some GREAT consistency with velocity as well: (this is for a mild load)


Starline 6mm Creedmoor brass is a winner because of the following:

  • It’s made here in the USA
  • It’s available in small and large primer pocket configurations
  • Great consistency and performance
  • It’s typically available! (always good when you’re talking reloading components)
  • It’s very cost effective for the performance it yields (about 60% the cost of top-shelf brass brands)

Midsouth Shooters Supply Has it!

If you’re looking for Starline 6mm Creedmoor brass, you can find it both at Starline’s website, and from Midsouth Shooters Supply!

I’d love to know what you think! Please drop a comment.


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