Confusing info

Curt

Curt

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I was reading in my Lyman manual that .257 Wby Mag 117 grain bullet, H1000 powder 64.0-69.0 grains. The Hodgdon site shows 117 grain bullet H1000 powder 70.0-74.0 grains. What do I believe?? The max in the Lyman Reloading manual is below the minimum listed on Hodgdon site...??? WTF ???
:confused:
 
It might be from the use of different components. Just did a quick check and the new Nosler manual's info is closer to the Lyman info, but with 115 gr bullets. I would try and cross reference another source or two just to be on the safe side.
 
Yeah a lot of listed loads are even hotter then the 74 gr of H1000 but that was with the 115gr. Id hold off on doing anything till i found out why.
 
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Why? Two different rifles could easily have that much discrepancy in load capability. many factors are involved. What is the throat length, does this rifle have ¼" of freebore and the other one less than .02.", does this one have a more generous chamber dimension than the other one? How about actual bore diameter, possibly .0002" - .0004" difference in this as well. Compound some of these factors and add powder from a different lot number, or brass that is heavier. On a case the size of the 257 Weatherby magnum, the difference could be as much as 6 - 10 grains. The bottom line is, you need to start nice and low and work up a load that is safe in YOUR rifle. The published loads are only rough guidelines, not stuff that you accept as gospel. Regards, Eagleye.
 
I have only one rifle in .257 Wby magnum. It is a stock Vanguard synthetic stocked and blued. The info I read in my Lyman reloading book shows the 257 Wby Mag with a 117 grain bullet and H1000 charged at min 64.0 grains and max is 69.0 grains. Hodgdon site (H1000 powder) shows 117 grain bullet with a charge of 70 minimum and 74.0 as a maximum. I was going to start at 72.0 grains, right in the middle of the loads on the Hodgdon site. I looked in my Lyman manual to confirm trim length and COL, and saw the listing for
H1000 and 117 grain bullet as 64-69 grains. If I were to use the middle of the road load from Hodgdon published, I would be significantly overloaded according to Lyman manual.
 
Alway best to error on the side of safety when reloading, as long as you don't reduce the load too much. Go with you Lyman Data to start and work up to the Hodgdon data.
 
Lyman data @ 64 grains minimum. Hodgdon 74.0 grains max. That is quite the spread. Maybe I will start at Lyman's max of 69.0, which is still 1.0 grain below Hodgdon's minimum.........
 
Here's one from Reloadersnest:

Load 10753 in caliber .257 Weatherby Magnum
LoadID 10753
Bullet Barnes TSX
BulletWeight 115 grs
Powder Hodgdon H1000
PowderWeight 72 grs
Primer Federal 215
Brass Make Weatherby
Barrel Length 26 (inches)
C.O.L (inches)
Velocity 3400 fps
Group 0.4 (inches by 3 shot at 100 yds)
Submitted Date 11/12/2005 3:51:00 PM
Submitted By Billy
Gun Info Weatherbu SBGM
Comment Tested and Sub-MOA out to 600 yds

Energy 2946 ft-lbs
TKO 14.36
OGW 780 lbs
IPSC PF 391


There are more with the 120grn Speer SP bullets ranging from 68-74grns of the H1000 as well. Looks like the Lee manual maybe more on the cautious side.
 
Barnes TSX bullets use up to 2grs. more powder to get the same preasure . using TSX load data with a NON-TSX bullet will possibly result in EXESSIVE preasure if max load for TSX used with non tsx bullets.
Read your manual and see what is said about excessive preasure . Be Safe
I've never reloaded for this cartridge myself but my manual shows min of 68grs. and a max of 73grs. for NON TSX BARNES bullets using H-1000.
the above data is to the lower end for a TSX bullet according to my manuals
Hornady manual doesn't even list h-1000 in 3rd.edition right up to 7th.for 257 wheatherby.
 
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