Direct answer: the right 40 S&W dies streamline sizing, seating, and crimping for dependable handloads. This guide compares five top sets to help shooters, hobbyists, and serious reloaders choose dies that fit their workflow, equipment, and goals. Best for beginners: all-in-one carbide sets with clear sizing and seating steps. Best for precision enthusiasts: NxGEN and premium Redding options with tight tolerances. Best for quick-trim workflows: Lee Quick Trim options.
| Product | Type | Best Use Case | Key Benefit |
|---|---|---|---|
| Lee Precision 90965 | 4-Die Set | New reloaders, 40 S&W and 10mm Auto | Carbide sizing with versatile usage |
| Lee Precision 90799 | 3-Die Set | Budget-conscious loaders | Three essential dies with reliable sizing |
| Lee Precision 91937 | 4-Die Breech Lock | Long-term brass life and color-coded setup | Smart Lock bushings for quick die ID |
| Redding NxGEN / Premium | Carbide Die Sets | Precision shooters | Advanced sizing, neck expansion, and seating control |
| Redding Premium Die Set | 3-Die Premium | High-end bottleneck and straight-wall use | Micrometer seating and unique expander |
Lee Precision 90965: 40 S&W / 10MM Auto Deluxe Carbide 4-Die Set
Best for dedicated hobbyists who reload both 40 S&W and 10mm Auto on a single bench workflow. This 4-die set includes carbide sizing and two seating/crimp components designed for straightforward adjustments and durable performance. The carbide sizing die reduces the need for case lube, speeding setup and cleanup. The multi-die assembly helps keep a consistent overall length for reputable bullet seating.
Which buyer benefits most: a cost-conscious shooter who wants reliable carbide performance without extra bells and whistles. Why selected: versatility for two common calibers and transport-friendly design make it a solid all-around option. Caution: verify overall cartridge length for your specific bullets to avoid seating depth variance.
Lee Precision 90799: 3 Die Carbide Set, .40 Smith & Wesson
Best for entry-level reloaders who want essential dies in a compact package. This three-die carbide set covers sizing, de-priming, and seating, focusing on straightforward operations. The included dies are designed to handle the 40 S&W cartridge reliably, with the potential to adapt to some related straight-wall cases in standard loads.
Who it’s for: a first-time reloader seeking a simple, dependable setup. Why chosen: a three-die configuration minimizes complexity while preserving precision. Caution: limited expansion and crimp control compared to higher-end sets; expect careful tuning for bullet-seating consistency.
Lee Precision 91937: 40 S&W/10Mm Breech Lock Carbide 4-Die Set
Best for reloaders who value quick die changes and color-coded identification. This Breech Lock carbides set includes a full complement of dies: sizing, expander, seating, and crimp. The kit uses colored Smart Lock bushings to quickly identify dies, reducing setup time during reload sessions.
Who it’s for: shooters who switch between calibers and want easy die identification. Why chosen: the Breech Lock system minimizes die changes and helps maintain consistent alignment. Caution: as with any carbide set, ensure proper case lubrication levels and start with lighter loads if unfamiliar with brass consistency.
LEE PRECISION 91208: Sz Carbide Die Only 40 S&W
Best for budget-minded reloaders who already own shell holders or want a dedicated carbide sizing die only. This die focuses on full-length sizing with carbide construction to ease operation and reduce lubrication needs.
Who it’s for: a reloader who wants a dedicated sizing die without a full die set. Why chosen: simplicity and low cost compared to full multi-die sets. Caution: carrying the full process requires compatible seating dies and expander; this option does not include those components.
Redding Reloading Three Die Set, 40 S&W/10mm Auto
Best for reloaders seeking precise resizing and consistent seating performance for straight-wall cases. This three-die set includes a full-length sizing die, expander die, and a conventional seating die, designed for dependable reloading sessions and tight tolerances.
Who it’s for: a serious shooter focused on accuracy and consistent case dimensions. Why chosen: Redding’s machining and tolerances emphasize long-term repeatability. Caution: may require more setup time to optimize seating depth for different bullets.
Redding NxGEN Carbide Die Set Straightwall
Best for high-end handloaders who prioritize advanced sizing performance and neck expansion control. The NxGEN carbide set features an upgraded sizing die, an expander die, and a premium seating die, designed to deliver smooth sizing and consistent bullet fit. The expanded neck tension helps uniform seating and reliable chamber fit.
Who it’s for: precision-focused shooters and competitive reloaders. Why chosen: advanced carbide sizing and a specialized expander support tight overall group potential. Caution: higher cost and a learning curve for fine-tuning neck tension and seating depth.
Redding Premium Die Set for Bottleneck Cartridges
Best for reloaders using mixed cartridge families who want a premium, adjustable seating option with a micrometer. This set includes a NxGEN carbide sizing die, a special expander, and a premium seating die with a micrometer control for precise seating depth.
Who it’s for: a high-volume competitor or careful collector who values micrometer-based adjustments. Why chosen: premium components and nuanced control support ultimate consistency. Caution: premium pricing and longer setup times for dialing in exact seating depths.
Buying Guide
What to consider when choosing 40 S&W / 10mm dies
- Die configuration: Decide between full 4-die or compact 3-die sets based on your experience and bench space. A 4-die set typically includes sizing, expander, seating, and a separate crimp (or a Breech Lock variant).
- Carbide vs steel: Carbide dies require less lubrication and offer longer wear life, but may cost more upfront. They’re ideal for frequent reloaders.
- Compatibility: Check whether your press uses standard 7/8-14 threads and Breech Lock systems. Some sets include locking bushings to speed changes.
- Neck expansion and seating control: For consistent bullet seating depth and neck tension, consider sets with an expander die and micrometer seating die or advanced NxGEN components.
- Quick-die identification: Sets with color-coded or Breech Lock bushings can reduce setup time, especially when switching calibers.
- Brass life and consistency: Expander dies and proper neck sizing can influence brass life and load uniformity over many reload cycles.
- Ease of use vs. precision: Beginner-friendly sets prioritize straightforward operation; high-precision sets emphasize micro-adjustments and uniformity across batches.
FAQ
- What is the main difference between a 3-die and a 4-die set for 40 S&W?
- Are carbide dies worth the extra cost?
- What is the benefit of Breech Lock in die sets?
- How important is neck expansion for 40 S&W / 10mm loads?
- Which dies are best for beginners?
- Do I need a micrometer seating die?
4-die sets add a separate crimping die or a dedicated seating/ crimp function, which can improve overall cartridge consistency for longer-term loads.
Yes for frequent reloaders who prefer minimal lubrication and longer wear life; carbide dies stay smooth with consistent sizing over many cycles.
Breech Lock simplifies die changes and reduces misalignment during setup, speeding up changes between calibers or reload runs.
Neck expansion can improve bullet seating uniformity and neck tension, which helps achieve consistent seating depth and more uniform loads.
Three-die carbide sets with clear sizing and seating steps are usually easiest to start with, offering reliable results without excessive setup complexity.
Micrometer seating dies provide precise control over seating depth, which is valuable for precision reloaders aiming for tight groupings.