Home Forums Hunting & Shooting Ask The Gunwriters 257 R 100 grain E-Tip help

During my day filled with ground squirrel whacking, I took a break and pulled out my chronograph and tested some single loads with H4350 and 100 grain Nosler E-tips in my wife's 257 Roberts.

I had loaded single loads from 43.0 grains up thru 46.0 grains in .5 grain increments, hoping to find a safe to shoot load up around 3000 fps. I was a bit surprised to see the velocities I got from a 22 inch barrel. 2.850 COAL, .145 off the lands, Win +P case and WLR primer.

43.0 = 2993 fps
43.5 = 3032 fps
I stopped here and decided not to shoot the rest of the loads, especially going as high as 46.0, which I believe would have been over pressure.

All I want for this rifle it to accurately shoot ~ 3000 fps. This is plenty fast for this cartridge and will not have excessive muzzle blast or recoil for my wife's shooting ability.

It seems the E-tips are indeed a bit sticky.

Next is to shoot some groups with 43.0 and 43.5 and see how she shoots.

Those velocities are by no means "hot" in a 22" .257 with 100-grain bullets. Generally 3100 fps is possible at pressures around 60,000 PSI--which is a little less than even the so-called +P pressures--but a lot less than .270 Winchester SAAMI pressures. But whatever....

Yaddio -

Nosler's Load Data (https://load-data.nosler.com/load-data/257-roberts/) puts a 100gr bullet at 3007fps when using 43.5gr of H4350.

It looks like you're right on track if all you wanted was 3000fps.

I think that's IMR 4350 powder listed on the Nosler website?

Agree. I think I could have elaborated a bit more.
43.5 grains of H4350 with a 100 TTSX today chrono'd at 2780. This surprised me, kinda low.
46.0 grains of H4350 with a 100 TTSX gave me about 3080, (same gun with a different barrel, so a bit of an inconsistent variable)
43.5 grains of H4350 with a 100 E-tip gave 3032 fps.
This lead me to believe that the E-tip might be sticky and gets higher pressure with less powder. At least similar velocities with less powder.

Next thing to do is just shoot some groups at these levels and see what it's doing for accuracy. If it doesn't group I'll try to go up a bit higher.

Dang, you're right! Just goes to show, never believe everything you see on the internet!