7 x 57 M-77 Tang Safety Accuracy Loads?

[gatling]

I've got a 200th year 7 x 57 Model 77 that is going to be the next load development project. I've cast around on here looking for accuracy loads and the only specifics I found recommended RL 19 for the RSI No. 1, and a few have mentioned that Rugers in general seem to prefer the heavier bullets. This is good, as I have a large coffee can full of 175 gr jacketed 7mm bullets (manufacturer unknown).

Does anybody have any specifics on loads this rifle might prefer?

Thanks in advance.

 

[Chief 101]

for the heavies I would start with H4831 powder...find the length according to the barrel and magazine...making sure you are well off the lands, .030" or more...consult your books and start where you are comfortable. Them year Mod 77,s can have really long throats so if you know where to start with the OAL you can be ahead of the game. The 7 Mauser data is conservative so you can certainly experiment on the high side of the data if you are confident you know what you are doing...play safe and have fun!

 

[Mobuck]

My best performance came from 140 grain Ballistic Tips and H414 but the optimum load was over the published data so I won't list it. The result was almost identical(very slightly higher fps) to current 7mm08 factory loads.