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Hornady · Magnum

300 RCM 178 gr ELD‑X® Precision Hunter®

0.278BC (G7)
178.0gr11.53 g
884m/s2900 fps
4506J3323 ft·lb
ManufacturerHornady
Calibre7.82 mm (.308")
Bullet weight178.0 gr  ·  11.53 g
Ballistic coefficient G10.552
Ballistic coefficient G70.278
Drag model usedG7
Muzzle velocity883.9 m/s  ·  2900 fps
Muzzle energy4506 J  ·  3323 ft·lb
Sectional density0.268
Form factori7 0.965  ·  i1 0.486
CategoryMagnum
SourceHornady website 2026-07-02 (verified)

Reading these numbers

Both a G1 and a G7 ballistic coefficient are published for this bullet. BallisticApp defaults to G7, because the G7 standard projectile is shaped like a modern boat-tail bullet and holds its coefficient far more steadily across the transonic range than G1 does.

Muzzle energy of 4506 J (3323 ft·lb) is computed from the bullet weight and muzzle velocity above, not quoted from the catalogue. Sectional density 0.268 describes weight per unit of frontal area; divided by the ballistic coefficient it gives the form factor, which is how much drag the shape adds over the standard projectile.

Among the 488 loads of this bore diameter in the database, this one's G7 BC of 0.278 is higher than 150 of them.

Similar 7.82 mm (.308") loads

Turn this into a drop table for your rifle.

These figures are the bullet's starting point. What you actually dial depends on your rifle's zero, the air you're shooting in and the wind on the day — BallisticApp solves that on the phone, offline, using the same G1/G7 tables and this database.

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