I found some interesting information on the web about converting an AR to FA. DISCLAIMER :: The link below is for informational purposes only. http://anvilsandinkstudios.com/AR15LightningLinkPlans.pdf Do not attempt to build or install on your weapon as it is equals prison time. for more information about LightningLink and Drop in auto sears checkout SWD Lightning Link DISCLAIMER :: Again these links are for informational purposes only. Naughty Monkey
The last couple of sentences in the second paragraph indicate heat treat would be wise. Unless one has a jeep bumper and a rock.