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GJW The History

  

This cartridge has an interesting history of development.  It was made by the swiss physicist Guido J. Wasser in cooperation with the DEVA (the most reputating German ballistic institute) based upon the 5.6 x 50 magnum cartridge.  It was ment to serve a dual purpose.

On the 1989 convention for german acoustic engineers, Wasser (who is known as the father of modern barrel oszillation measurements) had presented a method for measuring barrel-vibrations.  For this he needed a cartridge with excellent internal ballistics.

Wasser is also an internationally known handgun silhouette shooter, (and founding member of  IMSSU).  This sport involves shooting at different distances at 12mm (l/2 inch) thick steel plates, with the shape of animals.  Specially the 25 kg ram target at 200 meters is very hard to topple.  For this you need  a lot of striking energy.

The cartridge 7x49 GJW also served its  purpose in this area and proved itself at international matches  to be superior to a lot of other cartridges which were specially designed for this demanding sport.

Wasser also got attention with a bolt action pistol he developed, which is made out of titanium, and totally free of vibrations. In the mean time several manufacturers made comparable pistols for this sport in the 7 GJW caliber.  Among others the firm Keppler (Germany), Wutrich (Switzerland), Imperial Gun wich makes the Excalibur (England), Picra (Czech Republic), Loppo (Finland), MOA and RPM (USA) and also the firm Bullberry (USA) wich makes a 15 inch barrel for the well known Contender.

In the beginning of 1990 the cartridge (officially named the 7 x 49 GJW) passed the admission requierments and made it into the CIP lists (and it is also approved for production by IHMSA).

Looking at the performance and accuracy of this cartridge, it could very well be used for hunting.  As a special deer cartridge it had the advantage over smaller calibers of less damage to the game.

 

RELOADING

At first the brass had to be made from necking-up and fireforming 5.6 x 50 Magnum cases. 
But at the time of the erection of the worldorganisation for silhouetteshooting, the IMSSU, the Swiss amunition firm Thun marketed brass for the reloader.

These cases are of benchrest quality and are made in standard and nickel. 

The standard bullet for silhouetteshooting for this cartridge is the 168 grain Sierra matchking.  With this bullet, the 7 GJW has 43% less wind deflection than the 7 TCU.

Dies can be had from RCBS or Guido.

For hunting bullets ranging up to 150 grains are better suited.

 

PRECISION

The Frenchman Patric Lacher shot with a scoped silhouettepistol many 10 shot groups in the range of 15 mm. The best measuring 11 mm (.43 inch) at 200 meters, he is shooting groops like this on
a regular basis. This is about 1/4 MOA and as good as any sniper rifle only this was fired with a 10 inch barrel.  With his production gun, he won the unlimmited class at the '97 French championships.

At the first worldchampionships in 94 in Grasse, France, and at the third in Finland, Esko Lempola shot a second place in production with this cartridge.  He also won the unlimited catagorie at the Norwegian championships using his production gun from Loppo.

Guido J. Wasser shoot three times thru the horn of the ram - an obscure record with this cartridge.