120 gr. RCBS in .257 Roberts loads?

[Newtire]

Well, I finally got around to getting things together enough to shoot some j-word bullets out of my .257 Roberts I picked up a few weeks ago. I also scored a mould from a guy on here that is an RCBS 120 grain. I wondered if anyone had ever shot one of these and if any luck? I plan on starting with a few stepped up .243 style loads using 2400 & SR 4759.

[docone31]

We have a fellow on here who paper patched the 25-06, and loaded them hot!
I bet the .257 does real good that way.

[beagle]

Hey Newtire. I played some with the 25-120-SP and a HP version several years ago.

Here's my data:

25-120-SP HP Rifle M722 Rem/.257 Roberts
122.8 Grains

13 grains WC820 1625 FPS 2” @ 100 yards
16 grains Milsurp 4759 1817 FPS Not acc
18 grains 4198 1780 FPS 1” @ 100 Yards
14 grains WC820 1728 FPS 1.5”@100 Yards

25-120-SP
128.1 Grain

18 Grains 4198 1838 FPS 1”@100 Yards
11 Grains Unique 1637 FPS 2”@100 Yards
22 Grains 4895 1709 FPS 2”@100 Yards
25 Grains 4895 1907 FPS 2”@100 Yards
16 grains Milsurp 4759 1784 FPS 3”@100 Yards
13 Grains WC820 1581 FPS 3”@100 Yards

Pretty good bullet in my Roberts and I pulled off the scope and now use it with irons with the HP bullet.

They seem to be a bit sensitive to seating depth.

Use a nose first sizer as it's easy to bend the long, skinny rascals when seating the GC and sizing with a base first sizer./beagle

[Newtire]

Man, that's some real useful info. Now, Iwill have to get me a Lee sizer I reckon. I'll try the Lyman first as that's what I have and check it out. Never thought of that. Thanks for all the info! Mine is actually an Ackley Improved version so will make some adjustments as necessary maybe and report the results in a future post.

[Newtire]

Well, here's the range report on the .257 Ackley Improved with the 120 gr. RCBS boolit. Both batches of boolits were water-dropped wheelweights, lubed with Felix Lube in a Lyman sizer to .258" & Hornady checked.

I made 2-different loadings. I used 19 grains of H4198 in one batch & 18 grains of SR 4759 in the other. After sliding the nose of the boolit into the bore rather easily, I decided to coat that bore riding section with some liquid alox. I did this for 1/2 of each of the 2 different loadings.

The alox coated ones did appear to make a difference with the 19 grain H4198 load as the group was spread out not using the alox. The SR 4759 load seemed to make no difference. I fired the alox "enhanced" ones first so as to maybe coat the bore but it didn't seem to help one way or the other.

The H 4198 loads were all inside of 3/4" for the alox coated ones and 1-1/2" for the uncoated ones.

The SR 4759 loads were both inside of 1/2". I used Win Large Rifle primers but will give these a try with pistol primers in the future. The rifle is glass bedded with a 26" bull barrel so attribute the accuracy to that fact but that RCBS boolit sure does shoot. I had a .243 boolit that was long like that but it didn't shoot at all. Then again it wasn't an RCBS mould. Those boys with the green machines seem to know what they are doing. This shooting was all done at 50 yds. From now on, that rifle only goes to the 100 yd. range.

[JohnH]

I shoot that boolit in a 25-06 Encore. 19 grains of 2400 and Winchester large rifle primers are quite deadly on clay pigeons at 200 yards. 18 grains of 5744 is a very good load as is 12 grains of Unique. I've tried large pistol primers with a couple of loads and find the large rifle primers to consistantly give better groups. These are rather large cases and I believe the hotter or perhaps longer flash duration of the rifle primer to be a plus.

[Newtire]

I shoot that boolit in a 25-06 Encore. 19 grains of 2400 and Winchester large rifle primers are quite deadly on clay pigeons at 200 yards. 18 grains of 5744 is a very good load as is 12 grains of Unique. I've tried large pistol primers with a couple of loads and find the large rifle primers to consistantly give better groups. These are rather large cases and I believe the hotter or perhaps longer flash duration of the rifle primer to be a plus.
Thanks John for the information. I like the information on the Large Rifle as opposed to the Large Pistol primers as that's the next thing on my "list" to try. I will load a batch of each tomorrow and further dial this thing in. I plan on taking that trophy wheelweight (or maybe not!) this year from Bill's Brother-in-law depending on...alot of things! Thanks fror the alternatatives! Emmett Rifle Range, here I come! Looking forward to the shoot in Winnemucca! Hope to meet some of you there.

[runfiverun]

I have found with powders like 2400 in the big cases if you switch to the pistol primer you have to re-work the load a bit.
I use 18 grs of 2400 in the 0-6 case and a lr primer.
I have to use 19 grs with the lp primer to equal it.

[reloader28]

It makes nice boolits.
Unfortunately my 257 has the wrong twist for the heavy boolits. They were all hitting the target sideways and a 16" pattern at 50yds.

I dont have the wife convinced to let me get a new Cooper rifle yet to use these boolits in.[smilie=b:

[EW308]

Hello,
I've been considering buying a 257 Roberts or 25-06 for cast bullet shooting at the chickens at 200 meters, probably using the RCBS 120 grain cast bullet, I was wondering what the O.A.L. is in both the 257 Roberts and 25-06 ? Thank you Ed