GP 100 load question

Lead hammer

Lead hammer

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Finally got out to test a few loads with the Ruger.
The Speer manual calls for a max of 14.8gr of 2400 @1265fps (158 grain gold dot, I used cam pro)
My results were good with 14.5 gr @1224fps.
I also made some 38 powered 357 loads, using Unique. Speer claims 7.7 grains as max @ 1040fps, I used 6.9gr @1122 7.0gr@1132fps, 7.1gr @ 1143fps, 7.2gr@ 1151fps..
The brass looks fine, my speeds are much faster than the manual, is this a problem??? All of these Unique loads shot well, and had a small fps deviation of 52, 15, 22, 24fps.
Thanks
 
No its not a problem, it's just a different gun vs the factory test barrel. Could also be different primers, different crimp etc.
. If there is no pressure signs keep on shooting.
 
Spawn-Inc said:
No its not a problem, it's just a different gun vs the factory test barrel. Could also be different primers, different crimp etc.
. If there is no pressure signs keep on shooting.
Click to expand...
Primers looked good as well, cases ejected normal, I think with the velocity being consistent that pressure is not a problem. I will check out the min load again for Unique and try some slower ones and compare for accuracy. I was just surprised that they were clipping along pretty good. Save some powder too!!
 
Lead hammer

Please do not take this the wrong way, but if every reloader would read their entire manual from front to back they would learn a great deal.

In the Speer reloading manual #14 there is a chapter starting on page 769 called "Why Ballisticians Get Gray" by David Andrews. And on page 771 there is a chart with 30 listings for .357 revolvers and rifles with velocities and it shows a wide variation between revolvers and other firearms.

Bottom line if you look in the Lyman manual a universal receiver and barrel are used, this setup has NO cylinder gap and uses a minimum diameter chamber and bore to generate the highest possible pressures. In other manuals a specific firearm will be listed and a strain gauge will be glued to the test firearm to record the pressure. The end result of all this data gives you a "ball park estimate" of what the velocities and pressures will be in your firearm. The key words are "ball park estimate" because no two firearms are made exactly the same meaning nothing is written in stone when it come to reloading data.

Now go read "Why Ballisticians Get Gray" and look at page 771 and then check your hair color.
 
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