243 WIN. Varget Max. Charge

[KHOOKS]

I'm tring to work up a load in my .243. It's a Win. M70 .243 1/10 twist. I've worked up to 41.5gr Varget and was wondering if anyone has a around about max charge weight for Varget powder in the .243. I'm load Win. brass with BR@ primers and a 87gr amax. I'm just tring not to load to many rounds over pressure so I don't have to pull to many bullets.

Ken

 

[jeeptrash]

Re: 243 WIN. Varget Max. Charge

I have the same rifle and am just getting back into reloading so I am curious about this myself.

 

[Clark]

Re: 243 WIN. Varget Max. Charge

From my 6-1-30-2010 notes:

1903 Turkish Mauser built in Oberndorf Germany between 1903 and 1905, 24" A&B F54 moly chrome barrel 243 short chambered large ring, cut threads for small ring.
standard 243 reamer, chamber neck is a go with .277" pin gauge , which is minimum.
Bolt closes on headspace go gauge with slight increase in bolt handle force
With bullets seated at 2.71", chambering and ejecting cartridges, it looked like ~ .1" of lands marks.
So I backed off on the seating length to ~ 2.6" so the bullet would be ~ ~ .010" off the lands

42 gr Varget
.912" length 87 gr bullets
2.6" OAL, .405" extractor groove
Quickload predicts 66 kpsi
no egg (extractor groove growth)
spent primer hard to de cap

re used same case
43 gr Varget
.912" length 87 gr bullets
2.58" OAL, .405" extractor groove
Quickload predicts 72 kpsi
no egg (extractor groove growth)
spent primer hard to de cap

re used same case
44 gr Varget
.912" length 87 gr bullets
2.595" OAL, .405" extractor groove
Quickload predicts 77 kpsi
.001"egg (extractor groove growth)
spent primer easy to de cap

What does it all mean?
If the real limit is between 43 and 44 gr, then the max practical load with long brass life for me with my 4% margin reloading process control will be between 41.25 and 42.25 gr.
Another work up with smaller powder charge incremental steps between 43 and 44 gr would be necessary to narrow it down further.

 

[KHOOKS]

Re: 243 WIN. Varget Max. Charge

Ok this addes up with what I'm see. I loaded up the above loads in (5) lots of 5 shots with charge weights at 39.0/40.0/40.5/41.0/41.5. My best two 5 shot groups at 100y in 10-12mhp wind was right at 1.25 MOA in 47DEG temp. They were 39.0gr and 41.0gr so I think I'm going to work up and down by 0.2gr from 41.0gr and get the seating depth to a known number than out of the book numbers.

Thanks this is exactly the stuff I was looking for.