Do I need a Kimber .257 Bob???

[Oldtrader3]

I get 3400 fps from the 85 gr Nosler BT. The loading manuals for the .257 Roberts are still stuck at 40,000 PSI max from 1935! If you run a modern .257Roberts up to 60,000 PSI, you can do many things very close to a .25-06. My .257 is also in a full length action and is freebored. I can run it at least 100 fps faster than a standard rifle in a short action.

 

[SJB358]

I get 3400 fps from the 85 gr Nosler BT. The loading manuals for the .257 Roberts are still stuck at 40,000 PSI max from 1935! If you run a modern .357 up to 60,000 PSI, you can do many things very close to a .25-06. My .257 is also in a full length action and is freebored. I can run it at least 100 fps faster than a standard rifle in a short action.

Without a doubt. That 257 gives up very little to a 25-06 if it is set up properly.

Cartridge : .257 Roberts +P+ (not SAAMI)
Bullet : .257, 75, Hornady V-Max
Useable Case Capaci: 51.726 grain H2O = 3.359 cm³
Cartridge O.A.L. L6: 2.775 inch = 70.49 mm
Barrel Length : 24.0 inch = 609.6 mm

Predicted Data for Indicated Charges of the Following Powders.
Matching Maximum Pressure: 63000 psi, or 434 MPa
or a maximum loading ratio or filling of 110 %
These calculations refer to your specified settings in QuickLOAD 'Cartridge Dimensions' window.
C A U T I O N : any load listed can result in a powder charge that falls below minimum suggested
loads or exceeds maximum suggested loads as presented in current handloading manuals. Understand
that all of the listed powders can be unsuitable for the given combination of cartridge, bullet
and gun. Actual load order can vary, depending upon lot-to-lot powder and component variations.
USE ONLY FOR COMPARISON !

105 loads produced a Loading Ratio below user-defined minimum of 90%. These powders have been skipped.
Powder type Filling/Loading Ratio Charge Charge Vel. Prop.Burnt P max P muzz B_Time
% Grains Gramm fps % psi psi ms
--------------------------------- -----------------------------------------------------------------
Alliant Reloder-17 101.1 50.6 3.28 3732 99.1 63000 11023 0.919 ! Near Maximum !
Norma URP 109.6 51.7 3.35 3717 98.4 63000 11091 0.932 ! Near Maximum !
Ramshot Hunter 109.7 54.0 3.50 3717 96.8 63000 11286 0.929 ! Near Maximum !
Bofors RP19 ~approximation 109.6 51.7 3.35 3716 98.4 63000 11088 0.932 ! Near Maximum !
Hodgdon H414 103.8 52.3 3.39 3714 95.9 63000 11275 0.931 ! Near Maximum !
Winchester 760 103.8 52.3 3.39 3714 95.9 63000 11275 0.931 ! Near Maximum !
Vihtavuori N550 106.3 51.8 3.36 3712 98.2 63000 11189 0.938 ! Near Maximum !
Ramshot BigGame 102.3 50.4 3.26 3706 99.2 63000 10829 0.932 ! Near Maximum !
SNPE Vectan SP 11 102.4 50.4 3.27 3704 99.2 63000 10812 0.932 ! Near Maximum !
IMR 4895 98.9 47.2 3.06 3702 99.3 63000 10818 0.938 ! Near Maximum !
Winchester 748 91.8 47.1 3.05 3687 100.0 63000 10271 0.934 ! Near Maximum !
Bofors RP11 ~approximation 99.7 47.5 3.08 3686 98.9 63000 10722 0.939 ! Near Maximum !
Alliant Reloder-15 99.7 47.5 3.08 3686 98.9 63000 10722 0.939 ! Near Maximum !
Raufoss RA11 99.7 47.5 3.08 3686 98.9 63000 10722 0.939 ! Near Maximum !
IMR 3031 99.8 44.5 2.88 3686 100.0 63000 9822 0.936 ! Near Maximum !
Norma 203B 100.2 47.8 3.10 3686 99.3 63000 10671 0.940 ! Near Maximum !
Hodgdon BL-C2 94.2 49.0 3.18 3680 99.8 63000 10532 0.942 ! Near Maximum !
Norma 203 old 101.7 49.0 3.18 3677 99.7 63000 10538 0.950 ! Near Maximum !
Hodgdon H4895 96.3 45.9 2.97 3676 99.5 63000 10491 0.938 ! Near Maximum !
ADI AR 2206H 96.6 46.1 2.98 3670 99.2 63000 10505 0.938 ! Near Maximum !

 

[truck driver]

Thats a nice program you got there.

 

[SJB358]

Thats a nice program you got there.

Rodger, anytime you need some data, let us know. There are a few of us with the program.. We will be happy to run them when you get the 200's..

 

[truck driver]

Thanks Scotty
Back in the late 70s early 80's when I had my 257 built a friend who is a chemical engineer helped to develope a load that averaged out at close to 4000fps. he blended different powders to achieve optimum performance out off a 280 Remington on a Ruger 77 with a factory 24 inch barrel he used for bench rest in hunter class. The things he could due amazed me at the time and he worked up a load for my 26" custom barreled 257. He told me that if I had cut the barrel to a 28 inch length it would have exceeded 4000 fps.
He wouldn't tell what powders he used or what the mix ratio was and said it was for my own pertection. He did give me a small supply and told me to use it sparingly for he wouldn't make any more so when it was gone it was gone. I have none left and in away I'm glad because I would have burnt up a very accurate rifle barrel which still shoots great.

 

[Oldtrader3]

Gotta watch we engineers, we do develop some different loads sometimes!

 

[Savage99]

While the .257 Roberts has been a topic with us rifle aficionados for decades it never really caught on and is pretty much obsolete. You won't find ammo easily for it in stores.

None of the 57mm cartridges have been all that popular because they don't fit the actions made today. The Kimber 84M is a short action cartridge and your not going to have much fun or flexibility with that short magazine and throat.

I really like the Kimber rifles otherwise.

A reason the 257 R. never caught on is that it's bullets are kind of big ricochet wise for varmints and kind of small for big game.

I am now hunting in more open land and if I shoot a deer at say 280 yards I don't want it to go far and loose it on that other property. I want a bullet that will hammer it and the little Roberts is not it.

That's why it's obsolete.

I don't know how you would get ricochets from a bullet traveling at upwards to 4000fps with 75gr. Hps.
I used this caliber for ground hogs in central Md. and have missed them because the bullet would explode on contact with alfalfa. Ground hogs looked like they swollowed a granade when hit. As far as Deer go I have yet to have one run after being hit.
If I could have only one rifle in any caliber I could choose to hunt varmits and deer it would be the 257 Roberts.

Your way off by claiming the 257r will do near 4000 fps with a 75 gr! Hornady #9 shows a maximum of 3500fps!

Overall the 257r is too big for varmints and too small for deer. Best for nothing. That's why it's dead!

However it's a rifle cartridge and some like it so that's nice!

 

[Oldtrader3]

Obviously, I am not ringing in cogently on this conversation? I have only owned a bolt action .250 Savage, .257 Roberts (2 of them) and a .25-06, all of these but the present .257 Roberts were Winchester long actions and my current long action freebored FN Mauser. My loads may running be a little out of the box because this rifle in a long action and is freebored but I have been loading for .25 caliber bolt actions since about 1970 and killing deer with all of these rifles and a using a chronometer for load development.

Savage99, you had better believe that I can kill deer, DRT, with a .257 Roberts long action and freebore. Maybe a .250 Savage might be a stretch for some larger deer with a Model 99. However I would not bet too much money that a rigged up .257 Roberts in a long action, won't kill deer to 300+ yards nearly as well as a .25-06! Try Partitions, maybe those Berger bullets are not delivering the mail for killing power?

 

[truck driver]

Obviously, I am not ringing in cogently on this conversation? I have only owned a bolt action .250 Savage, .257 Roberts (2 of them) and a .25-06, all of these but the present .257 Roberts were Winchester long actions and my current long action freebored FN Mauser. My loads may running be a little out of the box because this rifle in a long action and is freebored but I have been loading for .25 caliber bolt actions since about 1970 and killing deer with all of these rifles and a using a chronometer for load development.

Savage99, you had better believe that I can kill deer, DRT, with a .257 Roberts long action and freebore. Maybe a .250 Savage might be a stretch for some larger deer with a Model 99. However I would not bet too much money that a rigged up .257 Roberts in a long action, won't kill deer to 300+ yards nearly as well as a .25-06! Try Partitions, maybe those Berger bullets are not delivering the mail for killing power?

I had mine built on a Remington 725 which is a long action that started life barreled in 30-06 and I wore the barrel out shooting ground hogs. The shop I bought it at also built custome rifles and had a 25 cal. barrel blank for sale which I bought. One of thier Smiths had opened up his on shop and didn't have a long wait time to build the rifle so I let him put it together for me.
To make the 257 sing he said I should consider a 257 Ackely with a long free bore. He didn't have an Ackely reamer in the shop but had a new 257 Roberts standard reamer so I left him chamber it with it and the long freebore with the intention of getting the AI reamer later which never happened since it shot so good. At the same time my rifle was being built I meet the Chemical Engineer who was doing load developement on the smith's range and we became friends. When the rifle was done he was impressed with what the freebore did for velocity and decided to see what he could do to ring the most out of it and that's how he came up with the load I mentioned I wish I had saved the notes and crony readings but I didn't that was back in the early 80s.
The 725 action is a modern 30 Remington action. My Smith said the action was a little over kill for the little Roberts cartridge but it has worked flawlessly since it was built.

 

[Oldtrader3]

I don't shoot the 75 grainers in my Roberts but I do shoot the 85's, 100's and 110's. I get 3395 fps out of the 85 grainers and 3140 fps out of the 110 grain Accubonds. If you don't think that a 110 AccuBond at 3100+ will not kill a deer, think again. I am getting 3140 fps out of Nosler 110 AccuBond factory ammo. I am betting the with Hybrid 100V that I can get more from the 110 Accubonds than from factory loads.

 

[cloverleaf]

.... :grin: :grin: .... a gunsmith friend tried to convince me that I should rechamber my FN300 long acton to 257 Bob. until he saw how well the 250 shot. Then he said, "you might want to leave it alone.... :lol: :lol: CL

 

[Oldtrader3]

CL, I had a Win 70, .250-3000 and it shot really well. In the bolt action frame, I could get 100 grain Partitions to about 2900 fps and it killed deer pretty well, plus it was really accurate.

 

[HOGWILD338-378]

If you wanted to shoot a higher BC bullet i would say buy it but me passing up the 257 Roy with the following numbers would be hard for me to do! 110 Gr AccuBond BC.418
100yd 200 yd 300yd 400 yd
2.70 3.26 0.00 -7.90

Be kind :lol: :lol: 3460 fps works for me :shock:

 

[Oldtrader3]

No doubt, the .257Roy cooks! However, I am also happy just par boiling.