Gentlemen I use the split case method to determine OAL. I assembled 4 resized and cut cases with 4 splits. I put a Hornady 175gr psp flat base bullet to just get a grip in the case mouth and chambered it. I did this 8 times and the cartrige extracted gave a average of 81.85mm. My rifle is a CZ 550 Lux. I backed of 2mm and smoked the bullet and rechambered the round again. I did this a few times and there appears to be soot taken off in a sort of circle , I could not see rifling marks engraved. I loaded a dummy round and it fits my magazine box easily and also the bolt closes with minimal force. I still see a shiny ring on the smoked bullet but no rifling engravings or is the shiny ring the start of the lands or ? Advice please! How will these bullets perform on bushbuck and wild pig at a velocity of around 2350fps at under 200m? I seated the bullets to a col of 78mm which is what Somchem list as max OAL for the 7x57. I am using Somchem S335 which I believe is the equal to IMR3031. Can anybody shed any light? Thanks in advance.

i'm not gonna comment on the ring thing you'll figure that out yourself.
but as long as you are not jamming the bullet into the rifling you are good.

the load you show will flatten just about anything the x57 is good to shoot.
which covers just about anything 4 legged up to @ 450kg or so.

I don't make it a habit of giving reloading advice but have reloaded enough in the last ten years or so to know that after you get the measurement to lands to seat bullet some .020" deeper in case or more for a hunting bullet or I do anyways. Times I get them close to lands and see what a rifle will do but most are not ever that close.
The 175 grain I shoot gets 48 grains of RL22 and seated out to 3.275", I figure this 7x57 Chilean Mauser 98 would take about anything I point at in my parts....should for what you claim you will as well.

What is oal? I take it you mean col? (Cartridge overall length)

QuickLoad says that the COL with that Hornady bullet should be 3.071 inches or 78 MM. The case length should be 2.244 or 57 MM.

What is right is what fits in the magazine and cycles in your rifle. I find 3 to 6 thousands off the lands works in my rifles. I do not own a 7X57.

Gerard I meant to say COL I picked your brain too much on the fone this week so I posted here so as not to hassle you!

quote:

Originally posted by lal:
Gerard I meant to say COL I picked your brain too much on the fone this week so I posted here so as not to hassle you!

I still use the term OAL and am not alone. roger

2mm is more jump than many of us use. Rather than the split case use an unaltered case if the bolt will not close seat a little deeper. Take the firing pin assy out of your bolt so you can feel the bolt closing pressure more easily.
If you think your round has been seated too short you can pull it out a little with an inertia bullet puller.
Once you think you have the exact number try a different bullet and case. Eventually you will figure out what to use.
The split case method has its merits but it does not tolerate feeding.

Bartsche,
One is never too old to learn. I looked around a bit and oal (as in overall length) is in widespread use. In fact, the abbreviation is used in several industries. Col (as in cartridge overall length), is peculiar to firearms alone.

I must say I have always regarded it as a misnomer but, there it is.