Home Forums Reloading Reloading Software 257 Roberts Quick Load

Can someone run a Quick load for me.
Hodgdon does not list this load and I would like to know the pressure. I understand it is a generality but the information would be a help in developing a load.

.257 Roberts
24" barrel
2.845 OAL
47.0gr H100v
110 Nosler Accubond.

Thank you for your help.

AJD

QuickLOAD can provide you with a calculated velocity and pressure for a given load, but that doesn't necessarily reflect the actual velocity and pressure being generated in your firearm. You still won't "know the pressure" from just running the numbers.

Many times the predicted velocity of a given load doesn't mesh with reality, which would also mean the predicted pressure necessarily wouldn't either. If you'd already clocked this load over a chronograph QuickLOAD may be able to give a general idea of what pressure this load is generating in your firearm.

If you'd still like the numbers from QuickLOAD, please provide the missing data.

Cartridge: .257 Roberts
Bullet: 110 Nosler Accubond
  Measured bullet length: ?
  Measured bullet boat-tail diameter*: ?
Powder: Hodgdon H100V
  Charge Weight: 47.0gr
Case:
  Length: ?
  H20 Capacity (measured to case mouth, no meniscus): ?
COAL: 2.845"
  Bullet touching/jammed into lands at COAL: ?
Barrel:
  Length: 24"
  Twist Rate*: ?

* Not critical data, but the better the inputs into a computer model, the better the outputs.

I understand this is theoretical.

Thank you Azar!

AJD

Edited to 2.230 Case Length

If you want anything resembling accurate data, I need real-world numbers for both of these. Your case length is way off. Perhaps you meant 2.225"? That would be a reasonable case length for the 257 Roberts. And while QuickLOAD does have a default case capacity (not a default Remington case capacity, just a general default) this is one of the more important measurements to get good results (perhaps the most important).

But to give you an idea, with a case length of 2.225" and a default case capacity of 56.0gr of H20 QuickLOAD predicts 3,136 fps @ 70,037 PSI.

With a +-5% variation in powder burn rate:
-5% 3,065 fps @ 62,906 PSI
+5% 3,193 fps @ 77,205 PSI

In any case, QuickLOAD believes your load to be overpressure.

Comparing to Hodgdon data, they show a max load for 115gr Partition at 46.0gr of H100V producing 3,049 fps @ 46,600 CUP. I'm not sure QuickLOAD is giving you very reliable data here...

Thanks I believe that to be correct as to QuickLoad providing reliable data in this instance.

Thank you,
AJD