Rifle
.17 Mach IV
An early .17-caliber centerfire wildcat on a shortened .222 Remington case, years ahead of factory rounds like the .17 Remington Fireball..
- Caliber
- 0.172″ · 4.369 mm
- Introduced
- 1962
- Case
- Bottleneck
- Parent
- .221 Remington Fireball
- Status
- Wildcat
- Introduced
- 1962
- Type
- Rifle
- Status
- Wildcat
- Availability
- Rare
- Primer
- Small Rifle
- Eff. range
- 250 yd
Ballistics
- Parent case
- .221 Remington Fireball
Representative trajectory — modeled from a single velocity input (no published BC for this cartridge yet).
Dimensionscase measurements · scale drawing · size vs familiar rounds
Case dimensions — the scale drawing at the top of the page is built from these.
reloading data · approximate| Measure | mm | in | ✓ |
|---|---|---|---|
| Bullet ⌀ | 4.37 | 0.172 | · |
| Neck ⌀ | 5.05 | 0.199 | ~ |
| Shoulder ⌀ | 9.14 | 0.360 | · |
| Shoulder angle | 30° | — | · |
| Base ⌀ | 9.53 | 0.375 | · |
| Rim ⌀ | 9.60 | 0.378 | · |
| Belt ⌀ | n/a | ||
| Rim thickness | 1.14 | 0.045 | · |
| Neck length | 5.16 | 0.203 | ≈ |
| Case length | 35.56 | 1.400 | · |
| Overall length | 46.48 | 1.830 | ~ |
Size vs familiar rounds
Drawn at true 1:1 — every case is accurate relative to the others. Absolute size depends on your screen's pixel density, so measuring one against a real ruler may be off. .17 Mach IV is highlighted below.
Reloading costestimate cost per round vs factory
Estimate your cost per round and how it compares to factory. Inputs are yours — nothing is stored.
Cost estimate only — not load data. Charge weight is your input; follow published manuals for safe charges.
Lineage
Connected reference
History
An early .17-caliber centerfire wildcat on a shortened .222 Remington case, years ahead of factory rounds like the .17 Remington Fireball.
FAQs
- What bullet diameter is .17 Mach IV?
- .17 Mach IV uses a 0.172″ (4.369 mm) diameter bullet.
- Is .17 Mach IV still in production?
- .17 Mach IV is wildcat; typical availability is rare.
- What is .17 Mach IV based on?
- .17 Mach IV is derived from the .222 Remington case.
Sources & provenance
- ManufacturerHornady Manufacturing — Hornady Obsolete Load Data — 17 Mach IV · bullet ⌀, velocity, grain weightsarchived
- SecondaryWolfe Publishing — Rifle Magazine — The .17 Mach IV Cartridge · year, velocity, parent_cartridgearchived
- Secondary.17 Mach IV — Wikipedia (pointer; cites O'Brien development) · parent_cartridge
Data & sources. Specs compiled from the Lindcott Armory reference; the trajectory is modeled (point-mass), not measured. See methodology. Spotted an error? Report it →
Lindcott Armory