Live fire trials against strv 103 like armor plates with bar armor (1962)

During the leadup to the adoption of the Strv 103 several live fire trials were carried out to determine what kind of armor should be used. In 1962 one such study was carried out with the goal of assesing the voulnurability of a 50mm plate at a 12,5 degree angle & to determine the effect of bar armor on armor penetration.

In the test a 105 mm Lvkan m/42 was used with full calibre APHE projectiles and a 105 mm L7 was used with L28A1 APDS.

Lvkan m/42 anti aircraft gun.

The target consisted of a 50 or 40 mm plate with 2 mm witness plates behind it.
In front of the main plate armor bars of 30 mm in diameter were mounted during some of the firings. The bars were mounted 100 mm apart and had a hardness of 500 hb.
Chart showing Round number, ammunition type, weight of powder charge, impact velocity, armor thickness, angle, if bar armor was mounted, results.

The reports notes that out of 9 full calibre rounds fired three penetrated the armor, but only after the thickness was reduced to 40 mm and the angle decresed to 18,8-22 dg with the bar armor showing little to no effect. None of the other full calibre rounds penetrated the 40 or 50 mm plate at an angle of 12,5- 13 dg, however one round fired at 17,5 dg did not penetrate but caused the armor to spall when it bounced. Out of 9 APDS rounds fired 3 in the range of 1363-1395m/s managed to penetrate the armor. Out of the 6 rounds that failed to penetrate three hit the bar armor and completely or partially shattered before impact with the main armor plate. The remaning 3 rounds (in the range of 1276-1371m/s) bounced off while leaving no damage to the witness plates.
The report concluded that the L28A1 could penetrate the 50mm plate at 12,5 dg up to a range of 1000 m. With the same round penetration was not achived when the bar armor was applied. While the full caliber round could only penetrate the armor at an angle of 17-19 degrees with a impact velocity of 900 m/s.