Just stumbled onto this thread. I was stationed at Eglin in the late 1970s and visited the gun/ammo people often through the early 1990s. Got to know Dale Davis pretty well. Eglin had LOTS of the 25mm blue tip TP rounds similar to the one Tony W illustrates near the beginning of this thread. During the 70s through early 90s (when the gun/ammo business was shut down in the Armament Lab) Eglin did most of their lab testing in 25mm because they had so many projectiles and because the test results could generally be scaled up to 30mm or down to 25mm. As late as 1991, the lab was doing work on high velocity aircraft guns in 25mm with a much broader engagement envelope in air-to-air combat. The ammo for these guns was a 25mm fully telescoped round with an aluminum or thin steel case, very much like the GAU-7 round.
When the Eglin Lab went out of the gun business all the 25mm PR projectiles went to the burial pit. I was fortunate enough to pick up a fair number of 4 or 5 variations of the TP loads. These are minor variations, and I think I still have a few if you'd like me to post photos, I could dig some out.
