Home Forums Hunting & Shooting Hunting Rifles Thinking about a 257 Rob AI build on M98

Hi All,

I have been absent from the forum for some time and now getting back on.

In my limited gun/rifle collection, I have the following centrefires:

270 Win - in Winchester pre-64 M70 fwt
308 Win - in Winchester pre-64 M70 fwt
308 Norman Magnum (identical too 30/338) - in a full classic custom rifle built on M98 some many years ago
375 Chatfield-Taylor (AKA 375/338WM) - in a Ruger M77

I have a spare Mauser 98 action ready for another build. As the smallest CF is 270 Win was thinking of something under that. As you can see I like classic calibres and so was thinking of a 257 Roberts Ackley Improved (AI). I have a gunsmith in the family so this is no issue. I know I could get a 26-06 or a 243 Win but really preferred a classic calibre and to do justice to the long (versus medium, i.e. 243/308 size) action.

I am happy for thoughts and comments on this.

Oh, yes. I am in Australia and moved a couple of years ago to Red Deer country in SE Queensland. .

I think that is a great choice. If I knew of a good gunsmith to tackle that type of project I would have liked one.

I didn't have your resources so I bought a 6.5 Creedmoor instead. Enjoy yourself.

Not sure I'd call a .257 AI a "classic" chambering. .257 Roberts absolutely, but throw on the AI and I think it loses some charm. Still a fine choice. I'd also throw in 6.5x55 for a similar classic round.

Mag
Stick with the standard Roberts. You won’t gain anything in the field from the AI.
GreggH

I always thought the RCBS version of the 257AI looked more balanced and also as if it would feed better. It's in the Hornady reloading book.

The 6.5x55 and the 257 Roberts would be pretty danged slick in that action and since you have a smith it makes it even better. Which barrel were you planning on using? Are there Australian made barrels or do you order them from the US?

Sounds like a great build. The 257 Ackley is a pretty neat cartridge as is the 6.5x55 or the Improved version and they both fit the 98 well. Good luck.

Personally, I'd choose the 25-06 over the 257 Roberts, especially on a M98 action.

And, if you want to AI something, AI the 25-06. That'll be a smoking fast rifle and deadly on deer.

Magnum308 -

In January of 2004 I picked up a used.257 Roberts at a gun show. Long-action Ruger. I was just ready to leave the show and go buy a .25-06, but couldn’t pass on the price for the Roberts. At the time my only centerfire bolt rifle was a 7mm RM. It quickly became my favorite rifle and has remained so.

For loads I use WW +P brass and +P load data. My Ruger has a ridiculously long throat so I seat the bullets out as far as I can while still maintaining full case/bullet contact throughout the length of the neck. (I’ve often joked the bullets couldn’t touch the lands with a stick.) SAAMI +P pressures are only 50,000 CUP and 58,000 PSI so I routinely go over max loads. In short, I’m running neck and neck with Nosler’s published .257 Roberts AI loads and getting excellent case life and no signs of excess pressure. Bullets and powders are 75g V-MAX/H4895/3609fps, Barnes 100g TTSX/H4350/3175fps, Nosler 110g AB/H4350/3163fps, and Nosler 120g Partition//H4831SX/2904fps and Swift 120g A-Frame/H4831SC/2947fps.

As much as I like my Roberts, if I was buying today it would be a .25-06. Or I would get a 6.5-06 or 6.5-06AI sporter-weight barrel to screw into an existing action, something to go with my heavy-barrel 6.5-06AI. The 6.5 bullet selection is far better than that for .25 caliber. I have a Savage action waiting for a new barrel. It already has a magnum bolt face so I’ll probably go 6.5PRC with it.

For my 6.5-06AI I purchase .25-06 brass and run it through the 6.5-06AI sizing die to expand the neck. Fireform loads have been extremely accurate using Hornady max data for the standard 6.5-06 with 140g A-MAX and H3831SC.

The Roberts proved to be a good choice and is not only my favorite but also that of my daughters. While I don’t regret the choice, it isn’t the way I would go today. But I’m not much for “traditional”.

Go with the Ackley Bob, if only because you'll never trim brass again.

Did the same but stayed with the std Roberts. Had a Mauser laying around that my Dad brought back from the war. Got a barrel from Green Mountain (they made the Adams & Bennet barrels for Midway), put it in a Boyds stock, after market trigger and viola!
Shoots MOA.

This ^^^. I got a 257 AI about 30 years ago, and it's been my go to rifle for deer. Completely happy with it. But truth be told you probably only gain about 50-75 fps over the standard 257 when loaded to equal pressures. But I don't ever recall having to trim brass!

I've owned at least one 257AI for nearly 40 years and think that it is a good cartridge, but the 25-06 is an easier way to reach the same level of performance. The 257AI has more of a "cool factor", but the 25-06 is easier and being a factory loaded cartridge would probably be easier to sell or trade down the line.. Those cartridges are two more or less equal ways to reach the same place, just pick the one that moves you more.

If I had to have a 257AI, I'd sell the 98, buy a 700 action and get it tubed in a 25-06. Be cheaper, easier, lighter with more parts available.

If the M98 is not negotiable, just go plain 257 Roberts.

Times are different now, but back in @1985, I had a 257AI built on a very nice FN Belgian military 98 Mauser action that I bought at a pawn shop for $25 in a bucket of junk. I went full bore on it at the time and I had special Oberndorf bottom metal and a Jantz Model 70 type safety installed along with a very slick Dayton Traister trigger and a Model 70 style bolt handle welded in place. The military action was untapped at the time that I bough it so I had that work done too. It still has the Leupold 7.5X scope on board in Buehler mounts that I bought specifically for it at the time. The barrel is a Douglas Air Gauge barrel. All of the metal was rust blued in a very nice soft satin finish. It all sits in a very nice but not fancy French walnut stock with a very simple but extremely nice custom checkering pattern cut at 22 lines per inch. It feels like velvet to the touch but it is very durable.

It is still one of my favorite rifles and it shoots extremely well. After saying that, I also own three other 257 Roberts rifles and a deer at 200 yards won't know which rifle I used. But the 257 AI case offers some benefits such as far less case trimming, and personally I simply like the looks of the minimal taper and sharp 40 degree shoulder to the 257AI cartridge. It reminds me of a smaller 284 Winchester-like case, and since the 284 Winchester is another favorite of mine, the 257AI fits well in my collection along with a couple of 284 Win bolt action rifles.

btw - the smith who did the action/barrel work opened up the feed rails ever so slightly and polished them so that the AI cartridge feeds like silk from the magazine.

I say go for it and enjoy what you end up with. If you have a smith in the family, the costs shouldn't be prohibitive like they might be otherwise today to get all of the work done that a Mauser action might require to totally get what you want. At the time with a growing family, I skipped far more than just a few lunches to get what I wanted.

EDIT: I dug the rifle out of a safe and took a few pictures of it to replace some that disappeared maybe 3-4 computers back...... Here is a picture of the complete rifle. Notice the cheek piece on the "wrong" side of the rifle. I am a lefty who learned to shoot a right handed bolt rifle as a kid (a Savage bolt action 22LR), so it was a necessary part of the custom stock. I've bought two left-handed bolt rifles in my lifetime and both went down the road at different times. Old habits, etc.......

That's a beauty!

We converted (4) surplus 98 Mausers to 257 Roberts Ackley in 2002 as a first project.
We had to buy a mill, a lathe, a welder, and lots of other stuff.
We used Lothar Walther barrels from Brownells.

Mine shot a 0.45" 5 shot group at 100 meters with 75 gr Vmax bullets.

Since then we got more lathes, mills, welders, and have rebarreled ~ 60 rifles with the 3 shops.

That M98 257RAI project was a turning point in our lives.

I think I would pass on the 257 and go with the 25-06.

I have been a 25 caliber fan for many years. My screen name on another forum was 25Cal. My first centerfire bolt action was a 25-06, and I used it for varmint and deer hunting for years. Since then, I have owned other 25 caliber rifles: 250 Savage, 250 Savage A.I., 257 Roberts, and 257 Roberts A.I.

I currently own two 250 Savage rifles, one a Savage 99 and the other a Savage Axis with E.R. Shaw aftermarket barrel. I also have another Axis rifle in 257 Roberts, again with an aftermarket E.R. Shaw barrel.

My favorite of all these? The Savage Axis with 257 Roberts barrel. It has a mild recoil, unlike the Remington 700 25-06, and it is very accurate. With handloads, a 117 grain bullet can be driven to 2,900 fps with ease. The handload I shot in my 25-06 pushed a 120 grain bullet to 3,000 fps, not a lot faster, and with more recoil. I'm 73, and have a bad right shoulder, so recoil is an issue for me, but maybe not for you.

If you have your heart set on the 257 A.I. by all means do it. I'm just relating my experiences.

Don't see how you can go wrong with that. A good action paired with a good round in a custom build. But I am pretty partial to my quarter bores too.