The 5.7×28mm is one of the more demanding cartridges an amateur can choose to load, and anyone researching dies for it should understand why before spending money. This page is an overview of what exists and what makes the cartridge awkward. It is not load data, and it does not link to retailers — current published data from the powder and bullet manufacturers is the only load information anyone should work from.
Why this cartridge is harder than it looks
Three things separate 5.7×28mm from a routine handgun cartridge:
- It is a bottleneck case at rifle pressures in a handgun-sized package. Sizing requires a conventional lubricated bottleneck process; the carbide sizing dies that make straight-wall pistol reloading so convenient do not apply here.
- Factory cases carry a polymer coating. Original specification brass has a coating intended to assist extraction in a delayed-blowback action. Sizing operations disturb it, and reloaders have argued for years about what that means for extraction and case life in different firearms.
- Case capacity is small and pressures are high, so charge weight tolerances are tight. Small errors that a large-capacity case would absorb are not absorbed here.
None of that makes it impossible — people load it successfully — but it is a poor choice as a first cartridge to learn on. It is also worth being honest that factory ammunition in this chambering has become far more available and far cheaper than it once was, which removes most of the original economic argument for loading it at all.
What a die set for this cartridge contains
Sets are normally two dies:
- A full-length sizing die, which returns the fired case to specification and, in most sets, deprimes it in the same stroke. Because the case is bottlenecked, it needs case lubricant — this is the step that goes wrong most often, and a stuck case is the usual result.
- A seating die, which seats the bullet to a set depth and, depending on the die, applies a light crimp.
Some reloaders add a separate expander or mouth-flaring die and a dedicated crimp die rather than relying on the seating die to do both jobs, which gives independent control over each operation.
Who makes them
Four names come up consistently in discussions of this cartridge, and all four have produced 5.7×28mm dies:
- Hornady — the set most experienced 5.7 reloaders name as their preference, generally on the basis of sizing consistency. Hornady dies use a removable spindle assembly, which makes clearing a problem easier than on some designs.
- RCBS — a long-established full-length sizing and seating set, widely used and widely available. The general view is that it works well, with a longer history of reported teething issues on this particular chambering than Hornady’s.
- Lee Precision — the budget option, and the one most likely to be in stock. Reloaders who own several sets typically describe the Lee dies as acceptable rather than preferred, which for an occasional loader may be entirely sufficient.
- Redding — a premium manufacturer whose dies are excellent in general, though this chambering has attracted a longer record of user complaints than their reputation elsewhere would suggest.
Specialist reloading retailers — the kind that stock dies for uncommon chamberings rather than general sporting goods shops — are where these sets actually appear in stock, and availability fluctuates.
The supporting equipment that matters more than the die brand
For this cartridge in particular, several items are not optional extras:
- A case gauge. Chamber tolerances vary between firearms in this chambering, and a gauge is how you confirm that a sized case will actually chamber before you have loaded fifty of them.
- Good case lubricant and a way to remove it. A stuck case in a sizing die is the classic failure here. A stuck-case remover is worth owning before you need it.
- An accurate scale. Given the small case capacity, a scale you trust to a tenth of a grain is not a luxury.
- A single-stage or a well-set-up turret press. This is not a cartridge on which to learn progressive-press troubleshooting.
Before you start
Work only from current published load data supplied by the powder and bullet manufacturers for this exact cartridge and bullet weight. Do not extrapolate from another cartridge, do not scale data up or down, and do not use load information from forum posts. Start at the published starting charge and work up while watching for pressure signs. Follow all applicable laws where you live — reloading is regulated differently across countries, states and localities, and it is your responsibility to know the rules that apply to you.
If the above reads as more involved than you expected, that is the useful conclusion: for most people, factory 5.7×28mm ammunition is now inexpensive and available enough that the case for loading it yourself is weaker than it was a decade ago.