🔧 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
300 gr (19.4 g) HP	Hodgdon H4198	44.0 gr 2.85 g	48.5 gr 3.14 g	1,850 fps	2.550	Hodgdon
300 gr (19.4 g) HP	IMR 4198	43.0 gr 2.79 g	47.5 gr 3.08 g	1,820 fps	2.550	IMR
405 gr (26.2 g) LFP	Hodgdon H4895	33.0 gr 2.14 g	37.0 gr 2.4 g	1,350 fps	2.550	Hodgdon
405 gr (26.2 g) LFP	Alliant Reloder 7	33.0 gr 2.14 g	36.5 gr 2.37 g	1,380 fps	2.550	Alliant
500 gr (32.4 g) FP	Hodgdon H4198	35.0 gr 2.27 g	39.0 gr 2.53 g	1,150 fps	2.550	Hodgdon
500 gr (32.4 g) FP	IMR 3031	36.0 gr 2.33 g	40.0 gr 2.59 g	1,200 fps	2.550	IMR

📐 Measurement Guide for Reloaders

Powder Charge

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.

Cartridge Overall Length (COAL)

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.

Cartridge Base to Ogive (CBTO)

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.

Case Length & Headspace

Brass stretches with firing. Measure case length to know when to trim. Use headspace comparators to check shoulder bump-back during sizing.

Neck Tension

The grip the brass has on the bullet. Measured with ball micrometers by comparing neck wall thickness before and after bullet seating.

Pressure Signs

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.