Between those two posts, I gotta go with 6.5X57

It'll make some nice velocity over the 7X57.

My father-in-law was a machinist and custom gun builder. We have 6 Mauser action builds, my favorite is the 25-06, he built it to mimic the Weatherby,. It is almost an exact copy, it has an old Redfield scope on that makes it look like a vintage 1950's Weatherby.

257 Roberts would be perfect

My 7x57ai is getting 1/2 moa or better running 3000 fps easy with 140 Nosler Accubonds. Don’t underestimate the 7x57ai

OK - walk me through this... Just looking a rough numbers...

- 6.5 x 57 looks like the equivalent of the 260 Remington and slightly slower than the 6.5 Creedmoor by 100fps
- 6.5-06 has the overall speed

What am I not considering .. looking for that "one thing" to push me in a direction...

My dad built a 6.5x06 on a Rem. 721 action with a Douglas barrel. Thing is a tack driver, easy to load for, mild recoil, and brass is easy to make.

I'm currently putting together a .264 Win Mag on an Interarms Mk. X action. Just need to get the stock work finished.

6.5-06 brass would essentially be everywhere since you could make it from and -06 case.

Post up a pic on your stock work... what did you choose for it ?

I've thought about the 6.5-06... and I like the specs.. but I also shoot a .280 so I am leaning into the 6.5x57... Seems to fill a nice spot..

While you can make 6.5-06 brass from 30-06 brass, it is much better to make it from 25-06 brass. if you make it from standard '06 brass you must be very careful about thick necks. Chances are you will have to turn necks or end up having too much neck tension, leading to excessive pressure.

The other thing to consider if you build a 6.5-06 over a 7X57AI or 280 Rem is barrel life. The 6.5-06, while being a speedy round and one that tends to be pretty accurate, will eat up a barrel. Not that much of an issue if you are building a hunting gun or occasional long-range steel banger, but if you plan on doing a lot of shooting with it, you will see the effects of throat erosion after 2500-3000 shots.

This is all based on my experience with 3 different 6.5-06 rifles.

Because published muzzle velocity is rarely correct, what is the case capacity of all three?

6.5 Creedmoor and .260 Rem make identical muzzle velocity when hand loaded. So no way is the 6.5x57 100 fps slower than the 6.5 Creedmoor. I'm not sure where you got that "data".

Possibly because people still load the X57 cartridges to the original low pressure specs. The .257 Roberts has been given a +P rating for modern firearms. The 6mm Remington and 7x57 are still woefully underrated by book specs.

I completely believe that.

Published data on .260 Rem and 6.5 Creedmoor is usually flat out wrong. As is the case with so many other cartridges.

See if you can find published data for 6.5 Creedmoor and .260 Rem having a 140 gr making 2800 fps MV from a 24" barrel. I doubt you'll find it. But, thousands of rounds have been safely fired at that velocity, even in +100° weather.

Some thing to remember is that a lot of the load data for the 7x57 is data that can be safely used in the older versions of the 7x57. With a modern action & barrel velocity should right there with 7-08, 308.

True... but my 7x57 is a 1915 Oberndorf and I am careful how I push that one.... its still a sweet rifle and does what I ask of it...

Hornady 10th edition.. 140gr Load data... 260 Rem max shows 2700fps, 6 x 57 max shows 2700fps, 6.5 Creedmoor max shows 2800fps. The Hornady manual is not the "Bible" but only a quick relative reference and I know the loads / speed shown are slower than what can be actually achieved. With some tweaking, of course a hand loader can do better. For a relative comparison it is fine.

Hornady gave their cartridge a 100 fps advantage. Tis not true.

That is what i am thinking, Nosler gives the 260 about a 100fps advantage over the 6.5 creedmoor.

In reality the 6.5x57, 6.5 creedmoor and 260 Remington are ballistic triplets for practical usage. One of the 3 has been around a whole lot longer than the others, so guess you could sy they are copy cats other than fitting in a short action better.

Agreed - I love the way Hornady wrote up the 6.5 Creedmoor... it has to be absolutely the best thing hands down ever... . .... but honestly the more I have looked at the 6.5x57, I like it. And, for me if fills a good niche and I think it will work really well in this action.

While we are at it.... who makes a really good quality, pre-fit, solid wood rifle stock. I have used Richards Microfit in the past for laminate..... but this one will be solid walnut and I'd like to kick it up a notch..

Saw this one on a Mini Howa posted this week, he said the stock is a Boyds Platinum Walnut stock not sure if it is the Claro XX or not

OK - this is my choice for the action.... going to go with a 6.5x57.

I've been looking at brass and see that PPU makes cases in 6.5x57 but has mixed reviews... anyone use PPU ?

Otherwise, the reading I have done indicates using 30-06 cases, trimming and then FL sizing in 6.5x57 die is far easier than starting with 7x57.

The other option is using 257 Roberts cases and necking up....this option seems the best

Thoughts, comments, wisdom are all appreciated !

PPU weights will probably vary more. The PPU I used ten years ago, seemed pretty heavy.

If Lapua makes 257 Roberts, that's the way I would go. Since you're going through the trouble, you might as well get brass that will last for a whole lot of firings. Annealing every second firing will make it last quite a while. 200 pieces of brass's per rifle is my personal minimum.

Completely agree on the 200 case minimum... looks like it is PPU, Nosler or Remington...no Lapua sadly... not a fan of RP brass like I once was... Nosler seems to be the option.. It's P+ and they sure do like their stuff $$$...

Nosler brass is quite good. Maybe as good as Lapua.

My 7mm-08 Nosler brass is on firing number 5. Starting to see about 20% might be getting loose primer pockets.

For what I loaded in 6.5X57 I used Hornady 257 Roberts brass if I remember correctly, already had it at the house for my 257 anyway and I think it would be the easiest route to use theroberts brass as you are only necking it up .007 inches.

S&B makes loads for 6.5x57 also and if you can find it the brass isn't bad and much more consistent from my use than PPU.

Quality Cartridge Brass will be expensive but you can get good brass with the correct headstamp.