.338 Lapua Magnum
The ultimate long-range sniper cartridge. Designed to defeat body armor at 1000 meters. Holds the record for longest confirmed sniper kill. Extreme recoil and cost — a specialist's tool. Dominant in extreme long-range competition.
Best For
Ballistics (Typical Factory Load)
🔧 Handloading Data
Reference load data for experienced reloaders. Always start at the start charge and work up. Consult official manuals before loading.
| Bullet | Powder | Start | Max | Velocity | COAL | Source |
|---|---|---|---|---|---|---|
| 250 gr (16.2 g) HPBT | Hodgdon H1000 | 86.0 gr 5.57 g |
90.0 gr 5.83 g |
2,900 fps | 3.680" | Hodgdon |
| 300 gr (19.4 g) SMK | Alliant Reloder 25 | 82.0 gr 5.31 g |
86.0 gr 5.57 g |
2,750 fps | 3.680" | Hodgdon |
📐 Measurement Guide for Reloaders
Measured in grains (1 grain ≈ 0.065 grams) using precision digital or mechanical scales. Maintaining strict powder weight is crucial for safety and velocity consistency.
Total length from case base to bullet tip. Checked with digital calipers. Must be within manufacturer's specified range to fit and feed from your firearm's magazine.
Precision shooters measure to the ogive — the curved part of the bullet that first contacts the rifling — for more accurate bullet seating depth and consistency.
Brass stretches with firing. Measure case length to know when to trim. Use headspace comparators to check shoulder bump-back during sizing.
The grip the brass has on the bullet. Measured with ball micrometers by comparing neck wall thickness before and after bullet seating.
Inspect fired brass for over-pressure: flattened primers, ejector marks, case head expansion. If unsure, reduce charge and consult your load manual.
⚠️ Always consult established reloading manuals (Hodgdon, Hornady, Lyman) for your specific bullet and powder combinations. For experienced reloaders only.
Technical Specifications
| Bullet Diameter | 8.6 mm |
| Case Length | 83.53 mm |
| Max Chamber Pressure | 43,000 PSI |
| Type | Rifle |