I did some load development, loaded on a single stage and all. Which doesn’t happen often enough these days! Got TT-33 shooting to very high 1200fps (almost 1300) using 70N (yes, I still have a stash) and Hornady 90gr jacketed bullets (#31000).
Load data was a bit of a challange, I could have easily (educated) guessed a starting point, but I did get access to Quickload model data, which in hindsight was off and VERY over estimated, but safe.
4.x gr at around 900-1020fps, failed entirely or struggled cycle the gun.
5.2gr at around 1212fps - VERY pleasant shooter.
5.5gr at around 1282fps (one round cracked 1300fps) - also VERY pleasant shooter, but definitely feeling more oomph and muzzle climb. More pushy than snappy.
Both very easy to shoot and reasonably accurate. Actually, I really enjoy shooting that firearm, a lot. Military loads are around 1400fps, so I am almost there, really keen to see how they shoot. However, I am convinced that there’s also a sweet spot somewhere between 5.2 and 5.5 that I might look at, because I really want to shoot it in a Service match with it.
Mold received, I am going to crank out some DIY bullets, shooting jacketed is not sustainable. And brass… Oh boy… Not exactly cheap or common, I got enough to keep me going very casually, but not if I want to shoot a match and account for 5% brass loss. Apparently it’s possibly to form brass from 223 cases. Cut, form, ream to reduce brass thickness on the neck. I ordered 7.7mm and 7.6mm drill bits to test the theory… I have some 223 to play with. Hopefully it works well, in which case I will buy a few killos of 223 and work with them.
We shall see how that goes, if it works, I’ll be pretty happy with it.