deactivating M25 tracers

We have a boatload of M25 tracer bullets.  Sounded like fun and during the bugger-all of certain parts of the Obama presidency, there were no other milsurp reloading components to be had (at prices I was willing to pay).  The tracers were priced attractively for the time, and everything is cheaper by the boatload.  They weigh in the range of 138 to 142 grains. 

Unaltered M25 tracer bullets, showing cavity and copper cup in tail. 

To render them safe(r) for regular range use, they must be deactivated. One intert00bs writer suggested hot glue to fill the cavity in the tail.  That writer might have had tongue in cheek, thinking that the hot glue would ignite the tracer compound.  Nah, another writer said you really have to nail the cup with a prolonged propane torch to set them off.  We filled about a hundred tracer tails with hot glue without incident. 

Note:  these aren't truly deactivated for purposes of range safety.  We expect them to not ignite when fired from our rifles.  But beat a few of these into the berm and leave them there, and somebody else can hit them with their bullets, and they'll start the grass fire that we didn't.  So, not good enough. 

Besides, one application for these tracers is in 7.62x39, but the M25 bullet is some 6mm longer than a 147gr FMJ, and that cavity full of glue takes up space that is needed for propellant. IMR4198's starting-ish charge of 24.5gr won't fit with the glue-filled bullet seated to magazine length. 

We poked holes in the copper cups of another hundred with a masonry nail, and immersed the bullets in mineral spirits to contaminate the tracer compound.  Some pale gray powder popped out of some with the nail.  More was found washing around in the mineral spirits after the bullets were taken out.  They air-dried for an hour then tumbled in clean walnut. 

These fit with 27-plus grains of H4895 (compressing?), and plenty of room for 27-plus grains of WC844, in the x39 case.  Two charge-weight ladders are ready for next range day. 

L to R, unaltered M25 tracer, tracer with glue-filled cavity, tracer with punctured cup and oil-wet tracer compound.