TESTED: Bullet Central Micron Dies

Everything I do is about precision, from building rifles to reloading. Today I’m testing the Micron Precision series of dies from Bullet Central! (Use the code URMICRON15 to save 15%!)

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About Micron Dies

The Micron Precision series includes bushing sizing dies, threaded seating dies, and arbor seating dies for a variety of calibers, all designed with cartridge-specific considerations.

I have one of each for 6 GT. Both the bushing sizing dies and threaded seating dies have dual rings for squareness and a split ring to help preserve the setting.

From Bullet Central:

With over 40 years of rifle competition experience, Bullet Central proudly presents the Micron Precision Seater Die Series. Our extensive testing of various seater dies revealed several common issues that can compromise the accuracy of your reloading process. Our new series addresses these problems head-on, offering unmatched precision and reliability.

Common Issues with Traditional Seater Dies:

- Inconsistent Seating Depth: Often caused by poor designs, loose parts, or a generic approach.
- Inaccurate Adjustments: Many dies lack a precise method to adjust seating depth, leading to guesswork.
- Oversized Chambers: These allow brass to shift, resulting in non-concentric alignment with the seater stem.
- Loose Seater Stems: Misalignment and improper contact with the ogive are common issues.
- Misaligned Lock Rings: Can cause misalignment with the press, especially in threaded seaters.

The Micron Precision Seater Die Series Advantage

Designed and manufactured entirely in-house to our exact specifications, the Micron Precision Seater Die Series represents the pinnacle of reloading technology. We have invested heavily in state-of-the-art CNC machinery to ensure each die meets the highest standards of straightness and precision.

Key Features of the Micron Precision Seater Die Series:

- Superior Precision: Advanced CNC machining and processes deliver exceptional straightness and accuracy.
- Reamer Cut Chambers: Ensure proper case alignment, closely mimicking a barrel chamber.
- Innovative Die-Loc Lock-Ring System: Features two precisely machined rings that keep the die perfectly perpendicular to the press, preventing misalignment typical with single lock rings.

Proven by Top Competitors

The Micron Precision Seater Die Series has been rigorously tested and trusted by the world’s leading rifle competitors. Whether you’re shooting in Benchrest or Barricade competitions, investing in a Micron Precision Seater Die ensures your brass is handled with the utmost care after each firing. A reliable seater die is crucial for any reloading setup, and we are committed to being your top choice.

Experience Unparalleled Accuracy

Choose the Micron Precision Seater Die Series by Bullet Central for a reloading experience that sets new standards in precision and reliability. Elevate your reloading process and achieve the accuracy you’ve always desired.

It only takes holding these dies to recognize their extreme quality and attention to detail. The surface finish is excellent with extremely fine knurling.

Micron arbor dies have a different design, but still features a split design with a micrometer locking ring on the bottom and thimble/upper portion to adjust the overall height.

Testing

I have previously-fired 6 GT cases that have been annealed in the AMP Mark II DB and lubed with some Imperial case sizing wax.

Setting up the Micron Bushing Sizer die is just like setting up any other die.

I threaded the die into the Area 419 ZERO press with the rings locked together and the crossbolt torqued down to prevent them from moving.

I bottomed the die out against the shellholder, backed it off half a turn, and incrementally cranked it down, checking with a comparator until the shoulder was bumped down 0.0015”.

After a few tries, everything was working incredibly smoothly. If you need to adjust the decapper, loosen the nut on the rod and crank the pin up and down.

This operation is independent of the bushing.

I primed all the cases using the Primal Rights Competition Primer Seater and charged them with 37.0 grains of H4350.

Dispensing Powder with the RCBS ChargeMaster Link

Next it was time to look at the Micron Threaded Seating Die.

I indexed the turret on the ZERO press and screwed the die partway in.

I used a loaded 6mm GT round as a reference, screwing the die in until I felt it hit something, then backing it off slightly. To keep this setting, I locked the rings in place, ensuring I could see the scale on the die. I verified that the thimble was free spinning. This means that the die is hitting the shoulder, but the stem is not contacting the ogive of the bullet.

This is amended by cranking the thimble down until it hits and running the scale up to meet it. I decided to use one of my favorite projectiles, Berger 6mm 105 Grain Hybrid Target bullets.

To get the utmost precision, be sure to check the first round you complete with a comparator or compare cartridge overall length to the dummy.

If I’m using a bullet with a machined tip like the Hornady A-Tip and don’t feel the need to be overly precise, I stop here.

If I’m loading match ammunition, I want to know where the ogive of the bullet is relative to the lands. If you need to adjust the seating depth, simply crack the torque between the scale and thimble, adjust the lower portion up or down, and secure the cap back down to the scale. This design leaves no creep in the setting. As I seated each bullet I noticed that the neck tension was perfect.

I also seated some bullets using the Micron arbor seating die on a K+M arbor press.

Start by setting the arbor over a reference round. From eye-level, crank the cap down until there is a gap, then find exactly where “zero” should be and secure the setting.

This is where the cap should be when the press is at the bottom of its stroke. Remove the reference cartridge and use the arbor press to seat bullets over the charged cases.

Don’t be alarmed if you notice some stickage due to extremely tight tolerances. A die like this is also ideal for use with an AMP Press.

Results

To see how each of the dies performed, I used a Hornady Lock-N-Load concentricity tool to measure runout.

Bullets seated using the Micron threaded seating die had approximately +/- 0.001” runout. This will do very well. Keep in mind that these cases were fired from a factory Bergara, not one of my full custom rifles.

This means that any of the runout in the fired cases will also translate to the bullet. Rounds loaded on the arbor press had approximately half the runout, +/- 0.0005”.

With all of my runout testing complete, it was time to shoot the ammunition! I placed my Bergara competition 6GT barreled action in a Foundation Centurion and headed to the mid-mountain range.