I just purchased reloading equipment and a friend who has been reloading for the past 25 years is taking me through the process.
I can't find data on the 7x57 R. I am shooting a Merkel K 1.
I was at Cabela's last night and one of the guys who is well versed in reloading said the 7x57 data is ok as long as you stay under 49000cup max pressure.
Any feedback is welcome
Thank you,
Steve

That sounds like good advice.
But how does one measure cup pressure?
Without a pressure barrel ( or modern strain gauges ) we cannot.
Is your Rifle pre-1960 or so?
Then stick with WW II load levels.

If you need more uumph go to a newer , modern round / rifle combo.

Gun was manufactured in 2001.
Thanks for the advice.

I just went through this with obtaining the same chambering in a Blaser K95 barrel. Both the K95 and the Merkel are chambered for other high intensity loads so I was completely surprised when Blaser USA told me to stick to 7x57R factory loads or similar handloads. IIRC, they boot a 140-gr bullet at about 2600 fps, or about 200 fps under a modern 7x57 rimless in a strong bolt action.

All I can think of is they are thinking liability in all this for some reason. Long story short, found my K95 has a very long throat so I can seat the 139-gr Hornady Interlock out so far there is barely any shank left in the case. Anyway, I'm starting with R17 and 46 grains and working up as far as I can go maxing at 50 under this bullet (if I get that far). I'm not saying this is safe in my rifle let alone yours but I am betting it is.

BTW, I passed this by John Barsness who also has a Merkel in 308 and he too felt they were hedging because of liability issues. Again, I can't really understand this for a rifle with an action handling the 300 Win Mag and assorted other high intensity cartridges.

Additionly, my barrel is not old but manufactored in the last coule years, so age isn't an issue either.

Best of luck and keep me in the loop with your findings.
George

Well, with an OAL of 3.19 with the 139-gr Horn IL i worked up to 50 grains of R 17 getting just over 2800 fps and best of all .75" in several 3-shot groups. I don't know if it's worth looking at anything else.

George, all I can say is that I use a similar load in a Ruger #1 in 7x57 and get similar results.