I did a lot of bump firing my SAR-1 yesterday, heating it up and seeing if I could set the handguards on fire.  They got way too hot to touch, turned black at the contact points, and smoked a lot, but no flames.

Had some problems though...  about 3-6 times per mag, the hammer would ride the bolt forward amd result in a chambered live round and no bang.  Had to pull the bolt back half-way to recock it and continue.  It never happened while firing normally, just bump-firing.  It also felt like it may have been doubling on occasion while bump-firing.

Any suggestions?

TIA