RMS 4+ J spring, aps2 standard, 13mm od spring
RMS stands for Rapax Modular spring.
Made to be used in Silverback, Novritsch, Modify and many other sniper rifle replicas.
Rapax airsoft springs are 13mm outer diameter, so they fit all above mentioned sniper replicas.
Rapax Modular Spring series are made with same quality standards as the Light Pull series springs. With durability and quality there made to give you the best sniper experience. The difference from light pull series is in its length (considerably shorter than light pull series), slightly harder pull, but increased silent shots. Also RMS springs are electrically coated to prevent rust which gives a more smooth operation on the spring guide.
RMS 4+ J spring come with two PETG printed 4mm spacers included in package, so you can adjust FPS/J according to your field limits.
Results : RMS 4+ J spring gives between 3.5J (with 300mm barrels) to 4.9J for longest barrels.
All springs are the same length, use the same material, have the same number of coils, ect.
Spring wire used for Rapax springs production is of the highest quality spring wire, ensuring a prolonged period of usage compared to other springs.
Tempering of these springs is made in a way to guarantee a long lifetime and very small FPS/Joule loss over time.
Springs are made in tight tolerances regarding diameter, they prevent the “twang” sound in airsoft sniper replicas.
Note: G-spec, the one with 300mm barrel always need harder spring to achieve same J/FPS than longer barrels.
You can see our HULK 4+J spring from lightpull series https://rapaxsprings.com/product/rapax-rapax-hulk-high-velocity-spring/
You can also visit “useful videos” page 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.