The best of two worlds

The Steambow ONYX is a collapsible, pneumatic self-cocking crossbow with the ergonomics of an AR-15. It is the first crossbow that was developed and built especially for the PowerUnit compressed air technology from Steambow and is optimized for a high rate of fire and the maximum number of cocking sequences from a single tank of air.

Depending on the bolt weight, the ONYX offers speeds of up to 330 fps and can be cocked in seconds – almost silently and with zero effort. It can also be used as a conventional crossbow without our PowerUnit compressed air system.

Thanks to its compatibility with AR-15 furniture, you can customize the ONYX to meet your needs, and you can collapse the limbs in seconds for convenient transport.

Bye now



330 fps / 225 lbs

See the Onyx in action

Only a large crossbow equipped with the PowerUnit becomes a Steambow. Look at how easy it is to handle. Starting from the transport to the launch. It is an experience how simple and at the same time spectacular a crossbow can work in this day and age.

  • Silent cocking

    You can cock the limbs almost silently within one second. When you relax the limbs after firing, a quiet hissing can be heard as the air escapes.


    High rate of fire

    The string is hooked into the latch with the limbs relaxed, the next bolt is loaded, and the Steambow is ready to be cocked and fired.


    Enhanced safety

    You decide when to cock the limbs, ideally just before firing. This precludes many dangerous situations.

  • Collapsible for easier transport

    You can use the quick-release pins to fold the limbs alongside the mainframe in seconds. This makes the crossbow narrow enough to fit easily in a normal bag.


    Safe loaded storage

    A Steambow can be stored and transported with a loaded bolt at zero risk of discharge. The optional disposable CO2 cartridges also allow a Steambow to be made ready in seconds after being stored for years.



    The automatic cocking function allows you to cock the Steambow without effort in any orientation and position, including in tight tree stands.

  • Tool-free string replacement

    The limbs of a conventional crossbow are under great tension even when the bow is not cocked. The string cannot be removed from the limbs without special tools or jigs. With a Steambow, you need no tools whatsoever to replace the string.


    Always ready to go

    Even if your air tank is empty, you have no compressor or backup tank, and you have used your last CO2 cartridge – you can also cock your Steambow manually with the right accessories.

  • Precision Manufacturing

    Made of high-quality aluminum alloys on state-of-the-art CNC machines. All surfaces are hard anodized with a matte finish. This ensures high performance and a long life.


    Longer Life

    The limbs of a conventional crossbow are always under tension and can lose their strength over time, especially when exposed to high temperatures. As the limbs of a Steambow are under no tension until pressure is applied, this risk is eliminated.

How the Onyx works

Effortless cocking, virtually tool-free maintenance, greatly enhanced safety, collapsible limbs for convenient transport: The PowerUnit pneumatic cocking system from Steambow can do it all.

  • Transport configuration

    The limbs are folded to the mainframe. This allows the Steambow to fit easily in a conventional bag, to be stored in tight spaces, or to be carried easily with a sling.

  • Onyx uncocked

    Hook the string into the latch. This requires no effort because the limbs are not under tension. In this configuration, the Steambow is absolutely safe because no energy is stored in the limbs.

  • Ready to fire

    Press the plunger on the main valve to silently cock the Steambow ONYX and make it ready to fire.

Technical data

72,4 - 80 cm*
3,4 kg
Power stroke
38,7 cm
Effective range
100 m
Draw weight
225 lbs / 102 kg
Bolt speed
330 fps / 100 m/s

* Adjustable buttstock



FAQ - frequently asked questions

Here you will find many helpful answers, tips and tricks about our products.


Here you can find the manuals for our products.