The development story of Gripfinger Shooting Support Spike – Making a good product even better
Jouko Komulainen, an inventor from Oulu, sees problems as nothing more than challenges waiting for a solution to be discovered. Komulainen’s inventions, such as the FixFork golf ball retriever and Gripfinger, a shooting support spike for firearms, are solutions developed to address issues encountered in various hobbies. Both inventions are patented products available for sale, and Komulainen already has more ideas in the pipeline.
This customer story focuses on Gripfinger, the support spike that attaches to firearms and grips onto tree trunks to stabilize aiming. Familiarly referred to as a shooting support spike, this product is designed to be attached to the accessory rail of a hunting firearm. It features a retractable steel spike that can be pressed against a tree trunk. This creates a new point of support for the firearm, ensuring a secure and stable grip during aiming. The product has now been developed into a second-generation version, incorporating new features that make it more versatile and compatible with various firearms and scopes.
Optotec has had the pleasure of being involved in enhancing this product, emphasizing functionality and versatility without compromising durability and quality.

Jouko Komulainen presenting his inventions
The Idea Quickly Evolved into a Clear Product Concept
The idea for the shooting support spike arose from the need for additional support when hunting moose. The concept was to provide a means of supporting the firearm against a tree, allowing even a heavy weapon to remain stable in the hunter’s hand during aiming. A viable approach for implementing this support was quickly discovered, as Komulainen, who had engaged in competitive shooting at a young age, applied a solution used in competition shooting gear, where a diopter sight was mounted on top of elevation blocks.
“I began to consider whether the support spike could be the same kind of accessory as elevation blocks that could be attached to the accessory rail. When contemplating the installation location for the support spike, I concluded that the optimal position would be beneath the scope since it is located at the center of the firearm, where the center of gravity also resides, thus ensuring effective stability during aiming. Installing the support spike in that specific spot would also be easy,” Komulainen explains the thought process behind the product idea.
Subsequently, Komulainen took action and began building a prototype of the product. He initially constructed the prototypes using hand tools until he had determined the most critical mechanical features and proportions of the product. Numerous factors had to be considered to ensure the product was user-friendly, durable, and compact enough to fit beneath the scope.
Once Komulainen had a functional prototype in hand, he sought advice and support for further developing his invention through an inventor community in Oulu. That led him to a designer at Optotec, with whom he started developing a market-ready product based on the prototype. With the assistance of the inventor community, Komulainen also received considerable support and advice regarding the intellectual property rights of the shooting support spike. Once the patent matters were settled, and a functional and desired product had been designed, Komulainen had a batch of the first Gripfinger version manufactured through a trusted subcontractor. The subcontractor also fine-tuned the product for better manufacturability.


From good to better
The further development of a functional product always presents its own challenges, particularly to ensure that the addition of new features does not inadvertently diminish the existing functionalities. In the case of Gripfinger, the compact size posed challenges as accommodating both the existing and new features required for versatile use without compromising their effectiveness proved to be a demanding task. Additionally, it was desired that the product would allow the installation of Optilock™ scope mounting rings on top of the support spike’s body.
In the previous version, the attachment to the accessory rail was done with a single bolt, but it was desired to make it more durable, so the natural solution was to use two attachment bolts. However, installing these two bolts side by side in the same plane was impossible due to limited space, as the threaded hole required for the bolt would collide with the hole intended for the spike. The placement of the threaded holes was studied carefully until suitable positions were found for both attachment bolts. Compared to the previous single-bolt attachment method, the two-bolt solution also reduced the bending of the mounting claw when the product is tightened onto the accessory rail.
The small size of the product also required careful consideration of manufacturing tolerances. The parts could not be too tightly fitted together to avoid excessive force or tools needed for the moving parts. On the other hand, excessive looseness would negatively affect the user experience and the durability of the product. When attaching it to the accessory rail, it was necessary to consider not only the geometry of the rail but also the fact that the mounting claw always bends slightly due to tightening. This bending is due to the diameter of the attachment bolts being slightly smaller than the installation holes in the claw.
The inventor continues to invent
Once Optotec had refined the details and tolerances of the product and prepared the necessary manufacturing documents, Komulainen gave his trusted subcontractor the green light to start the production. When the products came out of production, Komulainen was able to conclude that the product met the expectations he had placed on it.
“The outcome of the product development is exactly what I wanted. I am amazed at the level of expertise and the number of innovative people we have here in Oulu. I feel like I am in the hands of true professionals. The collaboration with Optotec has been pleasant and effortless. The innovative approach to work and the high-quality craftsmanship have convinced me,” says Jouko Komulainen.
Gripfinger has received a positive reception from hunters, and user experiences demonstrate that the product functions just as intended. Gripfinger is available for purchase at retailers such as Kärkkäinen and the asetarvike.com online store. The sales of the new version kicked off at the Northern Finland Wilderness Fair held in Ouluhalli in May, 2023, where Komulainen was exhibiting the product under his business name Woodclub. The development will go on to keep the product competitive and to better meet the needs and desires of customers. Additionally, Komulainen already has new ideas and inventions in mind, which the inventor will start implementing as soon as he has the time from his current projects.