Hello to you all.
Maybe someone can help me to get on track at the right direction (in a safe way).
My current project is to get my Zastava M76 semi-auto shootable with lead boolits.
I managed to slug the barrel, and I took measurements of the lead pill :
bore .311" - .3115"'
groove .3235"
The rifle is designed for the 8x57mm mauser cartride.
The rifle is a kind of copy of kalasnikov's ak47.
The barrel lenght is 55cm (source wikipedia).
To get this rifle shoot, I have a saeco mould (081) which gives me boolits of ca 182,5 grain (hardness of the metal is ca 15brinell).
I give the boolits a hornady gascheck and put them through a lee .323"sizer.
at this moment I know that the boolits are sized maybe too small (given the groove diameter I measure) but I haven't got the sizer made a bit wider yet, this will happen in the future.
When I make a dummy of this boolit, the metal is hitting the lands a little bit at a case overall length of 73,65mm.
My first concern is to find a safe load which is capable of repeating the rifle after every shot.
dont want to use this rifle as a straight pull (I have a Swiss K31 for doing that)
For my other rifles I use the "Harris-load" of ca 16 grain alliant 2400.
This was my startingpoint at my M76 journy;
2 weeks ago I loaded up five rounds with increasing amount of powder (alliant 2400).
The powderloads were; 16,0 // 16,5 // 17,0 // 17,5 // 18,0 grain.
after boolit seating I putted the cartridges through a lee factory crimp die.
I loaded them from the magazine, the highest load first;
None of the shots was capable of repeating the rifle. But the 18 and 17,5gn load were capable to eject the case without problems. The 17gn load I cant remember, the lowest two loads needed a bit assistance from me as I remember it right.
I don't have experience with "developing my own" loaddata, therefore this post;
I can do two things.
1. I can increase the amount of alliant 2400 till the rifle is repeating fully (or till I see signs of high pressure)
2. Or I use another (slower) powder.
If I do path .1:
I can't find loaddata with alliant 2400 powrder in the 8x57 cartridge (for lead boolits). But is there anybody who has experience with this powder in this cartridge with (almost) the same weight of boolit?
How far can I go up with the powder without making it hazardous. Unfortunately I don't have quickload to find a theoretical calculated pressure...
if I do path .2:
In the lyman cast bullit handbook(number 3 of 1980), loaddata for the 8x57 is given at page 208 for a 181grain boolit.
The mentioned powder H335 is also mentioned at the burn-rate table of the Vitahuori reloadingbooklet (issue 2012).
In that vitha burn-rate table Hodgdon(?) H335 is at the same level of Vithauori N133 powder.
This is triggering me, because a bottle of VV-N133 is standing in my little reloadingroom....
What I don't know is;
can I use the1980 Lyman loaddata for the H335 but then with the N133 powder? (just based on a comparisation of burn-rate).
What would you (experienced reloader who is not taking any risks) do in my case?
Thanks in advance for a helpful reply.
Wouter