257 Roberts range report

[Brians356]

You may do your Roberts a favor by trying RL-17 &/or Hodgdon Superformance - velocity, via the latter may well scare you to death! I have not been without a .257 Ack. Imp. (Roberts) since 1976, and have messed with many 25 Cal. cartridges - for hunting, the .257 Ack. Imp. remains my favorite.

Since its introduction, RL-17 has been my, "go to", .257 Ack. Imp. powder: 110 Gr. BT at 3330 FPS average, via both the 'ol Oehler & MagnetoSpeed chronographs - impressive, mild, and sub 1/2 MOA 5-shot groups via PacNor #3 contour, 24" BBLs. This velocity, for 110 Gr. bullet weight, is fully 220 FPS faster than any other [available] powder I have tried.

However, for the last outing, I decided to crack the seal on some SuperFormance, which had been sitting in the cabinet since its inception, in order to compare to my "pet" load. I was stunned to easily achieve MagnetoSpeed recordings of MV in excess of 3500 FPS! With no pressure signs! Via a decent bolt-action .257 Roberts, these should both provide a little more of a good thing! The BAD news: for these cartridges, there is no published DATA. RG

In 250 Ackley, RL-15 is ideal. Look at Sierra's data - RL-15 is their choice for both "accuracy load" and "hunting load" behind 75, 87/90, and 100-gr bullets.

How did you decide where to start with Superformance in your 257 Ackley with no published data?

In 6mm Rem, Superformance easily pushes a 70-gr bullet to 3800+ and 80-gr to 3500+ from a 24-in barrel at reasonable pressures.
-

 

[RGRobinett]

If one could get a 120-135 grain bullet with a respectable BC, in a 8.5-9 twist Roberts for 500 m Rams and 115 grain Bergers for everything else, might be magic in HP silhouette.

At risk of hijacking this thread, I am experimenting with a pair of Bartlein 1:8" twist barrels and 135 Gr. BT bullets - for cartridges of .257 Roberts/ .257 Ack. IMP/.25-06, it appears that this weight is beyond the point of diminishing returns: "on paper" (computer screen) a 125Gr. looks more promising - the combination of velocity & BC. Sadly, the making of these bullets is extremely time consuming, as the jackets must be drawn by hand - there simply is not enough interest to get one of the jacket makers to produce suitable jacket length.

In 250 Ackley, RL-15 is ideal. Look at Sierra's data - RL-15 is their choice for both "accuracy load" and "hunting load" behind 75, 87/90, and 100-gr bullets.

How did you decide where to start with Superformance in your 257 Ackley with no published data?

In 6mm Rem, Superformance easily pushes a 70-gr bullet to 3800+ and 80-gr to 3500+ from a 24-in barrel at reasonable pressures.
-

Sierra DATA, though useful, is neither magic, nor all inclusive - from .250 Ack. Imp. capacity, & up, for velocity, and with, at least, equal precision, RL-17 will, probably, "blow RL-15 out of the water" - most likely by about 200 FPS! But, the Sierra lab rats haven't figured this out yet!

When I decided to pop the seal on the Superformance, I employed the same logic as required with the RL-17, a combination of [un]common sense & extrapolation, based upon 50+ years of wildcatting. I do not employ case wrecking, high pressure, potentially dangerous loads, however, I do, by judicious use of a micrometer, identify the top end for each powder/bullet/barrel combination, then back off to a safe operating range which insures ready extraction and long case-life.

Locate an old Speer #7 loading manual, and read Jack O'Connor's load development article - it worked then, and it works today. There are a great many applications for the plethora of new powders,
for which there is no published DATA - I sometimes wonder if the lack of DATA isn't either, "a vast anti-velocity conspiracy", or an attempt to save all of the obsolete powders!RG

 

[Brians356]

Sierra DATA, though useful, is neither magic, nor all inclusive - from .250 Ack. Imp. capacity, & up, for velocity, and with, at least, equal precision, RL-17 will, probably, "blow RL-15 out of the water" - most likely by about 200 FPS! But, the Sierra lab rats havent figured this out yet!

You've said that before. I'm open minded about RL-17 in 250 AI. But have you actually verified it does "blow RL-15 out of the water" in 250 AI, or is this just a strong hunch on your part?
-

 

[RGRobinett]

You've said that before. I'm open minded about RL-17 in 250 AI. But have you actually verified it does "blow RL-15 out of the water" in 250 AI, or is this just a strong hunch on your part?
-

You'll have to figure that out for yourself - just be safe. RG

 

[Brians356]

You'll have to figure that out for yourself - just be safe. RG

I can only take that as a coy "I haven't actually tried it".
-

 

[SheepDog]

I was just looking at the Nosler load data this morning and they listed RL 25 as best in the Bob with a 120 grain bullet. Best velocity and the best accuracy. I believe I will stick with the H414 for now It seems to hold a lot of promise and I use it in my 06 as well.

 

[prasse]

I found places for 6mm, large calibers from 6.5 and up and this one for small stuff. If it is posted in the wrong area please feel free to move it.

I went to the range today but what made it special was my son and daughter-in-law came with me. I am going to make up names for them so if I forget you will know why:
Tom and his wife Shirley had picked up a new gun for Shirley to use hunting. It was a Remington semi-auto 3006. Now Shirley is almost as tall as my son, at just under 6' (he is 6' 4") and although she is slender she is no wimp. I was still doubtful about the 06 so I brought a 6mm x 30-30 and my 257 Roberts for her to try. After I sighted my 257 in with the new scope she had already decided the 30-06 was Tom's. After firing the 6mm x 30-30 she was in love! She fired the 257 a couple of times but decided in the end that she liked the 6mm. One of the nice things that came out of this was that my 257 actually showed some promise for accuracy. The loads we were using were just "junk" ammo I through together with some 100 grain HP Speer bullets and a charge of 45 grains of H414. The only ammo I had fired before this was factory Nosler 115 grain loads. They produced groups/ no patterns of 2.5 to 3 inches at 50 yards. My junk ammo produced groups of 1 to 1.25 inches at 100 yards. Now I feel better about working up some loads for this gun so I can use it for hunting. OH, since My son doesn't hunt I will have a new partner - and she's a lot better looking than my son!

I am novice .257 Roberts user, having bought a used Ruger No.1 recently. The gun come with some handloaded rounds with Sierra 90gr HPBT bullets. They shot fairly good, 3 shots in 20mm at 100m. I had Nosler Partitions on hand, both 100 and 120gr. Loaded a few rounds and went to the range. I wanted to make powerful loads and was positvely surprised by the accuracy and velocity of my loads. Both grouped 3 shots in 10mm (.4") at 100m(110 yards). Velocity out of the 26" barrel was 1050 m/sec ( 3465 fps) and 940 m/sec(3102 fps), respectively. Both loads gave easy extraction and no pressure signs in MY GUN. Meanwhile I bought all kinds of bullets for little money as well as 200 new PPU cases in 6,5X57. They work fine and after reforming have the same case capacit as the original WW cases. The gun seems to become my favorite huntung rifle for evrything here in Austria.