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257 Roberts, IMR4350, 115gr NBT

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https://forums.accuratereloading.com/eve/forums/a/tpc/f/2511043/m/7801026022

27 April 2016, 22:17
257 Roberts
257 Roberts, IMR4350, 115gr NBT
Been a long time since I have posted in this forum. Its good to be back snooping. I am looking for peoples loads and velocities with this [257R, 115gr bullet] combination or something very similar.

Took my Rem700 to Wyoming in 2013 with 41.0gr IMR4350 and she was a bit slow at 2625fps. Believe my gun has a 24" barrel. It worked, got a nice buck, but it can do better.

I have done a pressure test moving up from 41.0 and there are zero signs of pressure issues. IMRs data claims 45.5gr max with 115s at 2866 with a 24", Nosler's book says 40.0gr max with 115s at 2806 with a 24". That's a BIG discrepancy!

I have read of folks running 47+ grains with 115gr bullets but I am not planning on going that hot. Looking for something in the 2900fps range if possible.

Thanks for the feedback.
28 April 2016, 01:54
Texas Killartist
Handloader 231 had an article by Barsness (handloads that work) that said 43.0g of H4350 behind a 115g NP would get you there.
The 2010 Hodgdon info I have shows it's only possible (w/ their powders) w/ Hybrid 100V.
According to Hornady, you should try RL 19.
Alliant claims you can get there w/ RL 22 at +P pressures.
Hope this helps
28 April 2016, 04:15
dpcd
I sue 48 grains or 4850, with 120s but my Ruger has a long throat. Check your throat and seat the bullets as far out as you can and use all the powder space. Some of the 257 data is way too light for some unknown reason. There is no reason to load them shorter than your mag will take, or less than 55 K psi.
28 April 2016, 17:48
Snellstrom
My .257 is shooting 41.5 grains of IMR 4350 about 2880 fps with 117 grain Sierra's out of a 23 inch barrel, Husky 96 action. Pin point groups.
What trick are you guys using to get 48 grains of IMR 4350 in a .257 Roberts case?
28 April 2016, 19:29
bartsche
quote:
Originally posted by Snellstrom:

What trick are you guys using to get 48 grains of IMR 4350 in a .257 Roberts case?


old46 gr, was about it for me.It was pushing a 90gr.Sierra Didn't own a cronograph at the time. beerroger


Old age is a high price to pay for maturity!!! Some never pay and some pay and never reap the reward. Wisdom comes with age! Sometimes age comes alone..
28 April 2016, 19:34
dpcd
It is not a trick; as I said, my Ruger 77 has a long throat and I seat the bullets way out. Fill up the resulting space with powder. they still work in the magazine. They are only seated about .15 inch, but that is plenty.
29 April 2016, 21:37
Texas Killartist
The latest Hornady book shows them getting there w/ their 117g w/ (5) powders.
H & I 4350, I 4831, Superformance and RL 19.