Rapax HULK High Velocity Spring (4+J)
Thousands of happy users use our airsoft springs in their Silverback SRS/Tac41, Novritsch SSG10, SSG96, …
Springs are 13mm outer diameter, so they fit all above mentioned sniper replicas.
Joule may vary depending on the setup used on your sniper replica, as, piston weight, barrel length…
Results : Rapax HULK High Velocity spring gives between 3.5J (with 300mm barrels) to 4.9J for longest barrels.
We remind you that J is measuring just with heavy bb´s and not with 0.2. Please adjust hop-up for best flight path before measuring.
If the spring shoots more then your field limits are, please cut some of the coils without damaging the spring integrity. Instructions how to cut a spring are in video section here https://rapaxsprings.com/how-to-cut-airsoft-spring/
The first thing you will notice is a lighter pull compared to standard springs. In short: less effort for more joule. The Silverback M170 and Rapax Hulk spring need similar pull strength but the Rapax Hulk spring gives more FPS/joule in comparison.
All Hulk springs are the same length, use the same material, have the same number of coils, ect.
Rapax handmade springs – made in Europe to give you the best and most silent results for your sniper. Enjoy light bolt pull.
Spring wire used for Rapax springs production is of the highest quality spring wire, ensuring a prolonged period of usage compared to other springs.
We use spring tempering process in a way to guarantee a long lifetime and very small FPS/Joule loss over time.
Our springs prevent the “twang” sound in airsoft sniper replicas, we advice to use lithium grease on it.
You can also visit “useful videos” page on this web site to get more knowledge about Rapax springs and other topics. For example, most usefull for many would be the importance to find out how weighted pistons work.