I have had five rifles chambered for the Roberts but down to two now, both Hawkeyes, though one is matte blued and the other is gloss blued. Both have the same Leupold 2.5-8x36 scopes and look like peas in a pod. The only difference is the gloss blued rifle was bought second hand and had been long throated by the previous owner. When the same load is fired in both rifles with the bullets sat 30 thou off the lands, the velocity of the long throated rifle (LTR) is about 150 fps less than the standard throated rifle (STR) (100gn Hornady and 47gn H4350). It takes 49gn H4350 to reach the same velocity in the LTR as the STR indicating pressures should be about the same. However, it just seems a bit weird to be loading 49gn H4350 in the Bob, with 100gn bullets, so I tend to load 48gn meaning I settled for lower velocity in the LTR (STR 47gn H4350/100gn/3150 fps, LTR 48gn H4350/100gn/3090 fps). I guess this seems to go against the whole premise of long throating a rifle, i.e. to get more velocity. The throat has only been lengthened about 3 or 4 millimetres but it has had quite an impact on the velocity.
Both rifles have been bedded, floated and had the triggers worked and will shoot three shots into about 1/2 an inch or a wee bit more at 100m attesting to the quality of Ruger barrels. The other Roberts rifles I've owned were a rebarrelled Featherweight which I had rechambered to .25-06, a Ruger M77 in 95% condition which I had rebarrelled to 7x64 and a Ruger Ultralight that I had rebarrelled to .257 AI.
I guess the .257 Roberts is fading away but if you have a rifle and a set of dies you are good to go. There must still be a few fans here in Australia as when the shops get a supply of brass in every couple of years it disappears in a week or two. I have a 100 cases for each rifle (2 x Roberts and 1 x 257 AI) and have five bags of Winchester brass sitting on my shelf. With cartridges that are not that popular I tend to buy cases when I see them, not when I need them, so always have some on hand.
