Loading for 30 Luger 6 in barrel - early days - testing powders

[Kiwi]

Much excitement with the arrival of my Interarms Mauser Parabellum in .30 Luger. Of course the first step was to field strip and examine. The 'used' gun was bone dry and showed no signs of being fired, certainly not in many years if at all. A good oiling and reassembly and it was ready for the range.

Ignorance is not always bliss, I ripped a bit from my thumb loading the magazine not knowing to use the loading tool. Thumbs bleed profusely.
While waiting for my paperwork to clear I had purchased some Prvi Partizan, and RCBS dies (auction $30).
I started with the Prvi, The toggle would not snap closed, but with one in the breech then the magazine inserted it cycled fine, 1 jam in the first 15 rounds. I should clarify that as a bullseye shooter I am used to loading 5. Home, clean, inspect, re-oil.

I spend a couple of days reading the reloading section of this site, found 85gr projectiles at Graff (got a few hundred) and started calculating powder loads, from posted loads, powder burn speed charts, and my reloading booklets from Hercules and IMR, I ignored Winchester as the only powder I have is WST a fast powder and the posts here indicate the Luger prefers a medium to slow powder which makes sense given my Mauser has a .30 bore and 6 inch barrel. Thinking here was narrow barrel like a rifle compared to fat barrel like a 12ga.

I have
Alliant Unique initially for 20ga but availability and low price has me buying rather than reload, this powder has been repurposed to 45 Colt where the economics of reloading really pay.

Alliant Herco initially came with a 12ga press and was not used until tried out with .45acp and is now my favorite powder for that.

IMR SR 7625 I was given a tin and use it for .380 reloads where it performs well.

I decided to make test loads of each and see if the gun cycles. From reading here I wanted to avoid the Unique if possible given the descriptions of dirty, but if it works, it works.

First problem was the decapping and sizing die would not bell the case. Where it should bell a teensy bit it just started to compress the shoulder. With no belling, bullet seating was careful but successful.

I load 8 rounds, just like Noah two by two
4.8gr. Herco I thought this was much too light and expect an FTE
5.8 gr Herco generally uses a slightly higher charge than Unique with slightly lower pressure

5.1 gr Unique I used Hugh's sticky – 5gr did not cycle a 93gr, and 6gr working in a shorter (3-7/8) barrel did work for an 85gr.

4.2 gr SR 7625 - for this I compared the 2 Alliant powders with this for relative loads and pressures on a 9mm 115gr to come up with the powder weight

All these were at the light end and intended as starter loads purely to see if the gun would cycle

And back to the range where I load 2 magazines with 4 each and fire all printing a nice 5 shot cluster in 1.75 inches, the other 3 not too far away and more due to me getting used to the trigger than anything else. The only surprise was the light Herco cycling.
The toggle does now snap closed with a mag in so the earlier problem was probably due to no oil and no use.

Next I will retest the Herco at 4.8 with a fuller magazine, and the SR 7625 with a lighter load and fuller magazine.

Haven't had this much fun since kindergarten