Originally Posted by
falcon
caplock,
The 6mm x .75 thread for your Lyman Hawken is smaller than the standard 1/4 x 28 thread used in T/C rifles so I doubt you have a T/C nipple in by mistake, it would be tight an it would bugger up the threads on your bolster (or drum). If your nipple is fitting loose, and I'm not really sure what you're calling loose, you could do as Cayugad suggests and wrap the threads with Teflon tape but you may want to try a quality replacement nipple first.
BPS