The IV Core upgrade (Pronounced IVy) is a complete bolt assembly which comes with two bolts, the firing can, propshaft, and valve chamber. It important to note that since the 3.5 and GSL have the “bonnet” type bolt removal system they have a screw together propshaft while the IV Core upgrade does not.
Planet Eclipse has provided two bolts with the IV Core, the ST1 all metal bolt you see in the photos and the soft tipped bolt found originally in the GSL, and now standard equipment in the 3.5. Additional adjustment on the bolt kit is provided through a spring tension screw on the rear cap.
Players installing the IV core will benefit from the extreme amount of development that went into the GSL. The new IV core will provide a lower sound signature, softer shot and an over all smoother feel. Current 3.0 and 3.1 owners will see efficiency on par with the 3.5 and GSL markers, while older models will see a smaller although noticeable improvement.
This is exciting news for a lot of players that own any of the GEO line of Planet Eclipse paintball guns. It is really impressive to see a company not only look forward in developing new ideas and platforms, but also look back as to not abandon the supporters they have gained along the way.