I have seen only 1 Longstrike mod on the web and it was difficult to understand so i am going to make one.
Step 1: Opening It Up
You only have to focus on the main blaster unit not the extension or stock remove the bolt with a hammer claw and unscrew the screws.
Step 2: Modding
Now, for the mod you see the big spring take it out and just stretch it out not to much but not to little.
Step 3: Put It Back Together
Now make sure everything is in place and put the other side back on.Then screw everything back together and put the stock and bolt back on.
Step 4: Range
My Longstrike now shoots about 25 `. It may sound louder now