Why Can’t You Use a Fibre Wad with Steel Shot?

Why Can’t You Use a Fibre Wad with Steel Shot?

As the shooting community prepares for the move away from lead ammunition, one question we're hearing increasingly often is:

“If I currently shoot lead cartridges with fibre wads, will I be able to buy steel cartridges with fibre wads instead?”

The simple answer is no - conventional fibre wads aren't suitable for steel shot.

But that doesn't mean shooters who currently use fibre wad cartridges will be left without an alternative. The important thing is to understand why steel requires a different type of wad in the first place.

Why does lead work with a fibre wad? In a traditional lead cartridge with a fibre wad, the wad sits behind the shot charge. As the cartridge is fired, the fibre wad pushes the shot down the barrel, but it doesn't surround the pellets. This means that the lead shot comes into direct contact with the inside of the barrel. That's not a problem because lead is a relatively soft metal. Steel shot, however, is very different.

Why can't steel shot be used with a conventional fibre wad?

Steel is considerably harder than lead. If steel pellets were loaded above a conventional fibre wad, in the same way as lead, the pellets would come into direct contact with the bore as they travelled down the barrel at high speed. The result could be scoring and damage to the inside of the barrels. For that reason, steel shot needs to be contained within a full shot cup which keeps the pellets separated from the barrel throughout their journey through the gun.

The easiest way to remember it is:

Lead + Fibre Wad
The pellets can contact the barrel. Lead is soft, so this is acceptable.

Steel + Fibre Wad
The pellets can contact the barrel. Steel is much harder, creating a risk of barrel damage. ?

Steel + Full Cup Wad
The steel pellets are contained within the cup and isolated from the barrel. ?

Does a steel shot cup have to be plastic?

No, and this is the really important point for shooters and grounds currently using fibre wad ammunition. A full shot cup is necessary when using steel, but that cup does not have to be made from plastic. Gamebore has developed biodegradable full-cup wad systems specifically to provide the protection required for use with steel shot while offering an alternative for shooters who don't want, or aren't permitted, to leave conventional plastic wads in the environment.

So although there won't be a conventional steel + fibre wad cartridge, there are alternatives designed to fulfil the same environmental purpose.

Gamebore Bio-Wad and Bio-Wad Rapid

Gamebore currently has two biodegradable wad technologies for steel ammunition: Bio-Wad and Bio-Wad Rapid. Both form a full cup around the steel shot, preventing the pellets from contacting the bore and providing the necessary protection to the barrels. Both are microplastic-free and biodegradable, and neither requires industrial composting. They are designed to biodegrade naturally after being deposited in the field.

Bio-Wad Rapid is water-soluble and biodegrades within approximately 30 days.

Bio-Wad is not water-soluble, but biodegrades naturally in the field in a time-frame comparable with a conventional fibre wad.

For shooters currently choosing lead + fibre wad, therefore, the practical lead-free alternative is:

Lead + Fibre Wad → Steel + Bio-Wad

The material and design of the wad have changed because the properties of the shot have changed, but the objective remains the same: providing an effective cartridge without leaving persistent conventional plastic wads in the environment.

The wad does more than protect your barrels. There's another important reason we put so much development work into our steel wad systems. The wad isn't simply a barrier between the steel pellets and the barrel. It's an integral part of the performance of the cartridge.

Gamebore's Bio-Wad’s are specifically designed and injection moulded to tightly controlled specifications. The cup provides complete containment of the steel shot through the barrel, while the design of the wad and its gas-sealing characteristics play an important role in the internal ballistics of the cartridge. That means our wad systems are developed not only to provide complete barrel protection, but also to help deliver the consistency, velocity and downrange performance we expect from a Gamebore cartridge.

Whether the wad is conventional plastic, Bio-Wad or Bio-Wad Rapid, it isn't simply packaging for the shot - it's part of the cartridge's performance system.

Why do Gamebore steel game loads use double-base powder?

Changing from lead to steel isn't simply a case of swapping one type of pellet for another. Steel is around 30% less dense than lead, so achieving effective game-shooting performance requires careful consideration of the entire cartridge - including shot size, payload, wad design, velocity and propellant.

Gamebore uses carefully selected progressive double-base powders in its steel game loads. Their burning characteristics allow us to develop the velocity and ballistic performance required from steel while controlling pressure within the appropriate limits. It's another example of why a good steel cartridge has to be engineered as a complete system. The case, primer, propellant, wad and shot all have to work together.

What if my shoot or clay ground says “fibre wad only”?

This is likely to become an important distinction as we move towards 2029. Historically, “fibre wad only” has effectively meant “no conventional plastic wads” - usually because landowners or shooting grounds don't want persistent plastic wads left on the land. With steel ammunition, the terminology will need to evolve.

A conventional fibre wad cannot provide the shot containment necessary for steel, but biodegradable full-cup wad technology can provide the required barrel protection without leaving a conventional plastic wad behind. Shooters, clubs, grounds and landowners will therefore need to distinguish between a genuine requirement for a wad manufactured from traditional fibre and the underlying objective of the rule: preventing persistent plastic litter on the land.

For many clubs and shoots currently operating a fibre-only policy, biodegradable steel ammunition means changing more than simply the material used to make the pellets. Steel behaves differently to lead, and cartridges have to be designed accordingly. That's why you won't see a conventional fibre wad sitting underneath an unprotected charge of steel shot. Wad technology provides a practical route into the lead-free future.

Preparing for the move away from lead

The transition from lead means changing more than simply the material used to make the pellets. Steel behaves differently to lead, and cartridges have to be designed accordingly. That’s why you won’t see a conventional fibre wad sitting underneath an unprotected charge of steel shot. 

Instead, steel requires a full shot cup to protect the gun - and technologies such as Gamebore Bio-Wad and Bio-Wad Rapid allow us to provide that protection without relying on persistent conventional plastic wads. So if you're currently a fibre wad shooter wondering what you'll use when you make the switch from lead, the simplest answer is:

You won't be looking for steel + fibre. You'll be looking for steel + biodegradable full-cup wad.

Browse Gamebore's selection of steel cartridges for Clay and Game.


(Pictured: The water-soluble Bio-Wad Rapid during its biodegradation process)