Continuation regarding RS12 and RS20 for shotgun cartridges

Dear Reload Swiss RS Family,

A little while ago, we published some information on shotgun cartridges. Since then, the person who got in touch with us has continued to work on the subject and has very kindly sent us some additional information. As you’d expect, we’re more than happy to share the findings with other reloaders.

Calibre 12/70
Recipe with RS12Recipe with RS20
ShellFiocchi 12/70 T2 plasticFiocchi 12/70 T2 plastic
PrimerFiocchi 616 (high power)Fiocchi 616 (high power)
PowderRS12RS20
Load1.88g (29.0gr)2.20g (33.95gr)
Shot cupB&P Z2M-h21B&P Z2M-h15
Cork disk--Kal. 20 3.2mm
Shot32 g lead (2.7 mm)36 g lead (2.9 mm)
Crimp8-point star crimp6-point star crimp
V3 from a 74 cm barrel Approx. 407 m/s388 m/s
Pmax, estimateApprox. 520 barApprox. 580 bar
Calibre 12/76
Recipe with RS20
ShellFiocchi 12/76 T4-M plastic
PrimerFiocchi 616 (high power)
PowderRS20
Load2.38 g (36.7 gr)
Shot cupB&P Z2M-h21
Cork disk--
Shot36 g lead (3.1mm)
Crimp6-point star crimp
V3 from a 74 cm barrel 404 m/s
Pmax, estimateApprox. 580 bar

RS24 was also tested in combination with lead shot loads, but was found to be less suitable. However, a good recipe was found for using RS24 with harder shot.

Calibre 12/76
Recipe with RS24
ShellFiocchi 12/76 T4-M plastic
PrimerFiocchi 616 (high power)
PowderRS24
Load2.33 g (36.0 gr)
Shot cupGualandi TUBO48
Cork disk2x cal. 20 3.2 mm
Shot38.98 g copper (2.8-3.5 mm)
Crimp6-point star crimp
V2 from a 74 cm barrel 386 m/s
Pmax, estimateApprox. 900 bar

Use a knife to score a criss-cross pattern on the Gualandi shot cup over 60-100% of the shot height This ensures that the shot string is evenly distributed. Specification with copper shot: Hardness less than Vickers 50 HV/1. A ½ choke was used in this instance. Due to the hardness of the projectiles, it is advisable to use a choke that is suitable for steel shot.

We hope this information is helpful and inspires you in your own work. Wishing you all good shooting, great fun and every success with our powders.

Best regards,

Dominik Antenen