Board Thread:General Nerf discussion/@comment-46135863-20200619211405/@comment-27306930-20200619231756

Normally I would suggest buying an improved replacement spring, rather than buying and cannibalizing another blaster. It's cheaper and better. But it turns out the SlingFire has an internal clutch that needs to be modded if you upgrade the spring. As well as several other issues.

The good news is your spring will recover. In about 3 days. Leaving it primed won't permanently damage it. It's a well documented, well understood metallurgical process. The spring will "relax" and return to its original condition. No worries.

But the answer to your question is the Recon MkII, Elite/XD Alpha Trooper, Rampage, Elite XD Retaliator, and Slingfire springs are all compatible. So if you can find one of those at a yard sale or Goodwill, they will work.

If you want to learn more about upgrading the SlingFire spring, this youtube explains the installation of the Worker 5kg Spring Kit. Heads-up, it's more than just throwing a new spring in it 😉