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Dark Storm™ Precision Steel with Bio-Wad®

NEW for 2020 - Dark Storm™ Precision Steel with Gamebore's exclusive BioWad®

Building on the Quad Seal™ design, the Bio Wad® is a new full cup wad utilising the same cutting-edge material which is 100% environmentally safe.

It incorporates all the benefits of the Quad Seal™ with the addition of a new and unique cup section. The Bio Wad® has petals with newly designed unique 45 degree overlapping edges, giving complete barrel protection. Manufactured in-house by Gamebore, the new Bio Wad® is specifically designed for steel shot.

The high strength of the product means we can load not only standard steel loads but also high-performance steel cartridges for guns with the appropriate Fleur de Lys proof marks. The new cartridge is loaded using our exclusive Alliant double-base powder which gives outstanding downrange energy and all-weather performance that cannot be duplicated using single-base propellants.

Dark Storm™ Precision Steel is loaded with 32gms of shot in 3 (*High Performance Steel), 4 and 5 (Standard Performance Steel) in a 20/70mm HD case and will be available to order in late August. Limited Availability.

Shotgun proof and choke recommendations for each load:

5/32gms Standard Nitro Proof Modern Shotgun. Half choke maximum.

4/32gms Standard Nitro Proof Modern Shotgun. Half choke maximum.

3/32gms *High Performance Steel Proof Shotgun with Fleur de Lys stamp. CIP regulations state no choke restriction however we strongly advise Half Choke Maximum 


*Steel MPS Velocity calculated at Muzzle and falls within MAXIMUM CIP Momentum.


Standard Steel
Standard Steel ammunition can be used in any shotgun (other than Damascus/twist barrelled guns), in good order bearing any London or Birmingham proof symbols 1954 onwards. For pre 1954 shotguns guidance will be needed from the British Proof Authority. The shotgun must be chambered for the case length of the ammunition as a minimum. Longer chamber lengths can be used with shorter ammunition.

High Performance 
High Performance Steel ammunition can only be used in shotguns bearing a CIP Fleur de Lys proof mark. CIP recommends a MAXIMUM choke of half (.5mm) for shot sizes 4mm and larger. Please see above for Gamebore's own recommendations based on product performance, our experience, and safety. 


NEW Quad Seal™

Exclusive 4 Ring Gas Seal


Wad Petals

Cut at 45° to ensure full barrel protection





Technical performance

Velocity x Distance

The following graph shows the relationship between Velocity (MPS) and Distance (M) for the shot selected from the table below.

Cartridge Load gms Shot Size WAD Length mm Muzzle Velocity FPS Velocity MPS V1
Dark Storm™ Precision Steel with Bio-Wad® 32 4, 5 Bio Wad 20/70HD 1400 400
Dark Storm™ Precision Steel with Bio-Wad® 32 3 Bio Wad 20/70HD 1490 430 HP

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