Hi all Papa is looking to build a 7x57 for 15 year-old Granddaughter.

[Blue Avenger]

https://www.shawcustombarrels.com/sh...age-varmint/17
https://mcgowenbarrel.com/savage-pre-fit-barrels/
are a couple economy sites.
Google savage barrel and you will get a list. You will also need a tool kit to do it. If you are sure you will never want to change it again, get a quoit from a local smith.
You did mention prairie dogs.
.22-250 or .243 barrels, new take off could be an option.

[8mm RUM]

Well dang, about face!
I did not know Ruger Americans can change barrels the same way as Savage.
I have a brand new Ruger American in 30/06 that I inherited this year.
I have zero use for a '06 in fact I worked up a Varmint load with 110 bullets just so I might use it at all. Same bolt face same rotary magazine, just need a wrench, nut and barrel. It even has a Redfield 3X9 scope. I found a new Shaw Barrel chambered in 7x57 AI, 1x8 twist threaded muzzle blued,22 inch varmint taper, and shipped for less the the Savage.

PS do you think I need the "Deep" throat to take the Longer bullets?

[Dave Hoback]

LOL! “Long” throat sounds better. That is for the really long, super high BC 7mm pils, like the 190 Bergers, or Hornady A-Tips. Not likely if she doesn’t like recoil.

[8mm RUM]

Long sounds better then deep yup.
Is there an issue to have a long throat, and not use it? who knows how she or me will use it in 10 years. Weatherby has a LONG THROAT on most there rifles. We have several and don't shoot long bullets most you can't reach the lands with normal hunting bullets.

[PhilC]

I remember when you were setting her up with the Grendel, good to hear she's moving up! Need to stop in and say "hi" once in awhile you know where. :)

[Dave Hoback]

Long sounds better then deep yup.
Is there an issue to have a long throat, and not use it? who knows how she or me will use it in 10 years. Weatherby has a LONG THROAT on most there rifles. We have several and don't shoot long bullets most you can't reach the lands with normal hunting bullets.

Can’t run very short & very long bullets and still expect the best accuracy. Sure it will work. But if the barrel is throated for the heaviest/longest bullets, the lighter/shorter bullets will have a massive jump. Which is not always good. But they will still shoot fine.

By the way: Linda Lovelace would agree with the previous

[Highbrass]

Which ever rifle you decide to go with I would go with a bit more mainstream round.
Something like a 7mm-08 or a 243 Winchester or 6mm Creedmoor?
In the future she may need to purchase ammo off the shelf.
7x57 is not one you would likely find in WalMart.

[8mm RUM]

Most our rifles are odd balls, we load and keep 300/500 rounds for each.
Try to find 247 Weatherby, or 300 Norma mag. Even a mainstream gun can be hard to buy factory ammo 338.378, even my beloved 8mm rem mag.