Lee Precision 300 Blackout Rifle Precision Micrometer Bullet Seating Die

The Lee Precision 300 Blackout Rifle Precision Micrometer Bullet Seating Die brings repeatable, consistent seating depth to your handloaded ammunition. Whether you're loading match rounds for precision rifle work or field cartridges for subsonic hunting, this die gives you the control to dial in exact seating depth with a machinist's precision—without the precision-die price tag. The micrometer adjustment system reads like a standard depth gauge, making it intuitive for reloaders of any experience level.

The floating bullet guide is the standout feature here. It holds your case and bullet in perfect alignment during seating, then allows radial clearance so everything centers itself naturally—the result is minimal bullet runout, which translates to tighter groups and more reliable feeding. The guide is reversible too, so you can configure the die for seating alone or adjust it for simultaneous seating and crimping in a single stroke, a flexibility you won't find in most budget-friendly seating dies.

Build quality matters in a seating die, and Lee has machined and burnished the seating stem to handle nearly any bullet profile without marring the tip. The laser-engraved micrometer thimble and body are marked in thousandths of an inch, making it easy to dial in your desired seating depth and replicate it from round to round. When you're ready to load 300 Blackout, this die gives you the adjustment resolution and consistency that precision ammunition demands.

Key Features

• Precision micrometer adjustment with thousandths-of-an-inch divisions for repeatable seating depth
• Floating bullet guide minimizes bullet runout and ensures perfect case-to-bullet alignment
• Reversible guide allows configuration for seating alone or simultaneous seating and crimping
• Machined and burnished seating stem handles all common bullet point styles without damage
• Dead length seating: body contacts shell holder for uniform, precise depth control
• Laser-engraved markings for easy readability

Specifications

Frequently Asked Questions

What makes the floating bullet guide different?

The floating guide holds your case and bullet in alignment while allowing radial clearance, so they self-center during seating. This design minimizes bullet runout compared to fixed guides, resulting in better accuracy and more consistent ammunition.

Can I use this die for both seating and crimping?

Yes. The floating bullet guide is reversible—unthread it and reinstall it in the opposite orientation to configure the die for simultaneous seating and crimping in one stroke, eliminating a separate step.

Will this die mark or damage my bullets?

The seating stem is machined and burnished specifically to seat nearly any point style bullet without damage or marking to the tip.

How do I read and adjust the micrometer?

The micrometer thimble and body are laser-engraved with divisions representing one thousandth of an inch, marked just like a standard precision depth micrometer. Adjustment is infinitely variable, allowing you to dial in exact seating depth and repeat it consistently.