Has there ever been a Gyrojet light machine gun?, The wiki claims that some have been made, If so is the ammo the same as the pistols?
I’ve been doing extensive research on MBA gyrojets and other ordnance for about 10 years in preparation for the book I writing, which will be released next year. During this time, I interviewed (and taped) Robert Mainhardt formally on three occasions in Gilroy, California before he died in his sleep on July 3, 2006. I also had countless phone conversations with him to clear up some question I had. I also had many conversations with past MBA employees, and was very fortunate to acquire what was left of Mainhardt’s reference collection, including information about the light machine guns (and some not so light) MBA developed in the late 1960’s.
Some of MBA’s LMG’s were clip fed and others were belt fed. Most of them used a 13mm gyrojet with an entended length. Others used a so-called .50 BMG gyrojet that used a .50 BMG bullet jacket as it’s case. These didn’t work because the very high spin rate required to stabilize the long projectile caused the rockets to self destruct due to hoop stress caused by very high centrifugal force.
These machine guns will be covered in the book, and I have some pretty good illustrations to add interest. I’ll also show the machine gun patent model (verified by Mainhardt) I found on eBay by chance.
So…the answer to your question is yes, but none were adopted by any military organization, U.S. or foreign. Hope that helps.