I've been trying to find a load that would give good accuracy in my .257 Roberts, using 100 grain bullets. The rifle is a Ruger 77, old tang-safety model. Nothing has been altered on it from factory issue, except the trigger. Barrel is 22 inches long.

100 gr. Sierra BTSP bullet (100 gr. Hornady Interlock SP bullets are at least as good and usually better. But I ran out of them, so switched to the Sierras, which I had on hand.)
39 gr. IMR 4064
Remington brass
Federal 210 primer
Overall length, 2.88 inches
Crimped with Lee Factory Crimp Die
Velocity: 2770

My best group: 0.70 inch for 3 shots at 200 yards

Hmmm interesting. I was unable to find any good (accurate) loads other than with 115 gr.TSX's. I will go back and try your suggestion. What rifle are you using? Mine is a Ruger Ultralight.
Peter.

quote:

Originally posted by Peter:

What rifle are you using? Mine is a Ruger Ultralight.

Mine is the regular weight Ruger. It's the old one with red butt pad and tang safety. I bought it used, so I don't know how many rounds have been put through it. The rifling looks good.

Try 47 to 47.5 grains H4350 with 100 grain TSX. It's light's out...

My 100gr .257 load is also 39.0gr IMR 4064
With a 100gr Partition, win. case win mag primer
Have not chronographed it, but it consistantly groups five shots 3/4 inch at 100 yds.
Pre 64 model 70

Alan,

Welcome...I am located over in Grants Pass here...

Very nice rifle you speak of... a pre 64 Model 70 in 257! Class my friend... a very classic rifle!!!!

I also concure on the choice of load... 4064 in the 57mm case works great, be it in 6mm Rem, 6.5 x 57, 7 x 57 or 8 x 57!

Seafire,
Its nice to see someone else knows a fine rifle when they see one!
Grants Pass, I guess its a small world. I've been reading AR forums for a few years, just never have much to post about. Thanks for the welcome anyway.

quote:

Thanks for the welcome anyway.

Al:

My pet load exacty. In a 22" tube that load is running about 2900fps. I have interchanged TSX, Sierra Pro Hunter and Game King, Hornady spire pnt and Nosler Accubond all shot under 1/2 moa at 100 yards with that load. The TSX in 100gr is my hunting load though.

Perry

Yesterday I was measuring velocity of 26" barrel 257 Roberts Ackely Improved 100 gr HDY #2540 SP moly at 52~57 kpsi

3,236 fps
3,212 fps
3,244 fps


.37" 3 shot group at 50y
.8" 4 shot group at 100 yards [ cease fire was called before 5th shot]

This was with 42 gr of bulk surplus IMR4895 that thinks it is H322.

I think that the Ackley Roberts version should gain 60 fps over non-Ackley Roberts from additional case volume.
The rest of the gain is from higher pressure.

quote:

Originally posted by seafire/B17G:
Alan,

Welcome...I am located over in Grants Pass here...

Very nice rifle you speak of... a pre 64 Model 70 in 257! Class my friend... a very classic rifle!!!!

I also concure on the choice of load... 4064 in the 57mm case works great, be it in 6mm Rem, 6.5 x 57, 7 x 57 or 8 x 57!

Here are my 50 yr olds, Bob (257) and Tom (Swift). Both waiting on scope mounts. Bob gets a Balvar 8 and Tom gets a Unertl BV-20.

quote:

Originally posted by LE270:
I've been trying to find a load that would give good accuracy in my .257 Roberts, using 100 grain bullets. The rifle is a Ruger 77, old tang-safety model. Nothing has been altered on it from factory issue, except the trigger. Barrel is 22 inches long.

100 gr. Sierra BTSP bullet (100 gr. Hornady Interlock SP bullets are at least as good and usually better. But I ran out of them, so switched to the Sierras, which I had on hand.)
39 gr. IMR 4064
Remington brass
Federal 210 primer
Overall length, 2.88 inches
Crimped with Lee Factory Crimp Die
Velocity: 2770

My best group: 0.70 inch for 3 shots at 200 yards

My Dad's favorite load for his 257 Roberts 60 years ago was 39.0 grains of IMR 4064 using 100 grain bullets of the day.
My favorite load for my 257 Bob today is 45.0 grains of H-4350 with 100 grain Nosler Partitions. My rifle is a Ruger 77 also.

This is the exact load I use in my Roberts except I use the Speer Hot Core 100 gr.

My rifle is an 03-A3 with a 25" Shilen heavy sporter weight barrel. I get consistent 3/8" groups at 100 yds and 3/4" groups at 200 yds. In my rifle they chrono at 3000fps average.

Needless to say I love this rifle!

Funny you would post this now.
I am working up a load for my custom roberts and 100 grain bullets.
But i did'nt have any IMR-4064 on hand.
So far I have loaded H-4350 IMR-4350 and W-760, and will try H-414.
My other Roberts , A Ruger ultra light loves H-414. But I supose I should run out and get some 4064. As It has showed promise in the past.
But I highly recomend to all try H-414. 45 to 46.5 Grains. 46 grain gave me 3100 with a 100 grain T-shock from my little ruger...tj3006

I got to the range with both my .257 Roberts rifles this weekend. the mission was to find a 100 grain load for My custom springfield.
Well I now have 2. The 100 grain hornady flat base over 45.5 grains of H-414 gave me a .75 and another that was just over an inch.
That should be very close to 3000 , but I will chroney another time.
I did up some of my favorite deer load of 46 grains of H-414 under the 100 grain tripple shock. I loaded them about .030 off the lands and got 2 touching and 2 more about a half an inch apart. Problem was the 2 groups were an inch and a half apart.
But I remember I had some loaded for the ruger, and it has a shorter throat. So the bullets were seated deeper. And I put a some good groups on paper with them.
That load is screeming fast , 3140 out of the 20 inch ruger. Bet its over 3200 in the 24 inch custom. the hodgden web page gives presure of 44,500 with a sierra bullet and 45 grains , and the tripple shocks are suposed to lower presure , so it should be safe in a modern rifle,
I also got the load to print right at an inch with the ruger.
I was glad to see that as the load used to be great in it but not for the last year or so.
I thinbk trimming the brass was the answer.
...tj3006

quote:

Originally posted by seafire/B17G:

I also concure on the choice of load... 4064 in the 57mm case works great, be it in 6mm Rem...

I agree with that.

My 6mm Rem. is persnickety about what powder it likes. The only one that really works well in it is IMR4064.

Never shot a .257 but I have used the 100grn Sierra to toast the first 6 inches of the bore in a .25-06. I use 52 grns of IMR 4350. Groups runs about 5/8" for 5 shots and a bit smaller for 3.
It is one of those weird rifles that shoots groups nearly as small at 200 as at 100 yds.