www.gunslinger.net.nz
© 2008, Shane Cossar, New Zealand.
All rights reserved.  
Contact:  shane_cossar@hotmail.com

Gucci Gear Topics:

To achieve the full potential for consistent accuracy this system requires the best ammunition available.

AMMUNITION

.338 Lapua Magnum  
The .338 was conceived as a mid point between .308 and .50 calibres.  This translates to a downrange velocity that has low sensitivity to cross wind and a ‘flat’ trajectory resulting in an impact point only about 2m lower than the muzzle, at 1200m.

The AI AWM is chambered for .338 Lapua Magnum (8.58x71mm).
Lapua has several types of .338 Lapua Magnum ammunition available to civilian shooters.  Scenar is a hollow-point boat-tail (HPBT) for competition shooters.  Lock Base, common in military use, is a full-metal-jacket boat-tail (FMJBT) that maintains velocity supersonic up to 1300m and is effective to 1500m.  Naturalis LR is specifically for hunting and has a large bullet designed to spread on impact.  Armour piercing (AP) and Armour Piercing Incendiary (API) ammunition is only available to government organisations. 
Alternatively, Black Hills has both a .338 Lapua Magnum 250 and 300 grain Sierra Matchking round.

Table of Ammunition Ballistic Data

Weight

Velocity (m/s)
0m

Velocity (m/s)
1200m

Ballistic co-efficient >830 (m)

Impact point at 1200m (zeroed at 1100m)
(mm)

Scenar

16.2g / 250grains

905

421

0.675

-1976

Lock Base

16.2g / 250grains

900

379

0.662

-2255

Factory .338 Lapua Magnum ammunition is not commonly stocked by gunshops.  Belmont Ammunition and the NZ Ammunition Company are both distributors for Lapua ammunition and components.  However Lapua ammunition is not brought in very frequently.  If they have no stock they occasionally make a special order, in which case the minimum purchase of .338 Lapua Magnum ammunition will be a case of one type – 400 rounds.  As bulk quantities of ammunition must be shipped, expect a lead time from order to delivery of some three months. 
The Black Hills 250 grain Sierra Matchking ammunition is more readily available in New Zealand, either in boxes of 20 rounds or by case of 200 rounds.
In a home environment ammunition can usually be stored for up to five years before any significant degradation occurs.

Hand loads should generally outperform most factory ammunition.  As factory.338 Lapua Magnum ammunition is designed to achieve high levels of accuracy, do not expect hand loads to achieve any major improvements.  Therefore the decision to hand load or reload should be made on cost-savings.  Lapua cases can be reloaded a minimum of 10 times, so reloading will be significantly cheaper than purchasing factory ammunition. 

Disclaimer:  Shooting is potentially dangerous and damaged equipment can be expensive to fix.  You should confirm all changes to be made to your rifle system and shooting practices with your local gunsmith or gunshop owner.