Rifle · Proprietary
6mm HAGAR
High-capacity 6 mm AR-15 competition cartridge based on the .30 Remington case family..
- Caliber
- 0.243″ · 6.172 mm
- Introduced
- 2003
- Case
- Rimless
- Parent
- .30 Remington
- Primary use
- Competition, Target, Varmint
- Status
- Limited
- Introduced
- 2003
- Type
- Rifle
- Origin
- United States
- Inventor
- John Harrison, Sid Goodling
- Manufacturer
- Hornady (brass)
- Standard
- Proprietary
- Status
- Limited
- Availability
- Specialty
- Primer
- Small Rifle
- Case type
- Rimless
- Eff. range
- 800 yd
Ballistics
Velocity only, no drag model: no published ballistic coefficient is on file for 6mm HAGAR, so this is the shape gravity alone gives the advertised velocity. Drag would steepen it. The tool below solves real loads through their published G1 or G7 model.
Open in Ballistic Compare- Parent case
- .30 Remington
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.
SAAMI · approximate| Measure | mm | in | ✓ |
|---|---|---|---|
| Bullet ⌀ | 6.17 | 0.243 | · |
| Neck ⌀ | — | — | |
| Shoulder ⌀ | — | — | |
| Shoulder angle | 30° | — | ~ |
| Base ⌀ | 10.72 | 0.422 | ~ |
| Rim ⌀ | 10.72 | 0.422 | ~ |
| Belt ⌀ | n/a | ||
| Rim thickness | 1.24 | 0.049 | ~ |
| Neck length | — | — | |
| Case length | 45.09 | 1.775 | · |
| Overall length | 57.40 | 2.260 | ~ |
Missing a dimension for 6mm HAGAR? Some case measurements aren't in a published SAAMI/CIP drawing yet. Have a factory or reamer print? Send it → — verified hard-to-find data earns a free Lindcott sticker.
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
Designed ~2003 by John Harrison and Sid Goodling ("HAGAR" = Harrison-Goodling Automatic Rifle) for NRA High Power; Hornady produced brass from 2012 (never loaded ammo).
FAQs
- What bullet diameter is 6mm HAGAR?
- 6mm HAGAR uses a 0.243″ (6.172 mm) diameter bullet.
- Is 6mm HAGAR still in production?
- 6mm HAGAR is limited; typical availability is specialty.
- What is 6mm HAGAR used for?
- 6mm HAGAR is primarily used for competition, target, varmint.
- What is 6mm HAGAR based on?
- 6mm HAGAR is derived from the .30 Remington case.
Sources & provenance
- Secondary CartridgeCollector.net — 6mm HAGAR · year, bullet ⌀ archived
Data & sources. Specs compiled from the Lindcott Armory reference; the trajectory is modeled (point-mass), not measured. See methodology. Spotted an error? Report it →