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#1
10-13-2006, 11:15 PM
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7x57 Load Data
The day I've been waiting for since March finally rolled around: Clear skies, comfortable temperatures, the range open, and some time off work to work up loads for my 7x57. So here's the data....
My rifle is fairly long-throated. With 162 Hornady BTSP's I use a COL of 3.190", and am about .050" off the lands. That will probably produce lower pressure and velocity than many other rifles. The brass was new Remington brass, which seems to hold about .5 grain more powder than another type I've tried. Primers were CCI 200. The following data is for reference only, since your rifle WILL behave somewhat differently, and your bottle of powder is different from mine. Data shown are the best-fits results from regression of the raw data. That averages down the noise a bit, and gives a more reliable result. Pressure data were taken with the PressureTrace strain gage. Muzzle velocity was taken with a Shooting Chrony. Ambient temperature was 62-65F. I did not take the time to hook a thermocouple up to the barrel as I sometimes do, but I did let the barrel cool between shots so that it felt about 75F-ish. 162 Hornady BTSP, H4350, COL 3.190" Grains....PSI.........FPS 43.........34,402.....2380 44.........37,967.....2445 45.........41,533.....2510 46.........45,098.....2575 47.........48,663.....2640 48.........52,228.....2705 Comment: 3565 PSI per grain, 65 FPS per grain. 162 Hornady BTSP, RL19, COL 3.190" Grains....PSI............FPS 47..........43,524.......2481 48..........46,659.......2551 49..........49,794.......2622 50..........52,928.......2692 51..........56,063.......2762 Comments: 3135 PSI per grain, 70 FPS per grain 150 Sierra BTSP, H4350, COL 3.090" Grains.....PSI...........FPS 45..........34,677.......2507 46..........38,598.......2579 47..........42,250.......2652 48..........46,441.......2725 Comments: 3921 PSI per grain, 72.8 FPS per grain. 48 grains is getting near a full case. Might benefit from a slightly faster burning powder, or a little more H4350 if it will fit. Sample of 1: 52 grains very old H4831, which is a case full to the brim, and 150 Sierra, 44,000 PSI, 2635 FPS. 53 grains H4831SC, 150 Sierra, 2730 fps, no pressure data. This is a #1 contour barrel rifle, so it is fairly light. So far, it seems like an ideal combination of performance and weight. Last edited by denton; 10-14-2006 at 12:03 PM. 
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#3
10-14-2006, 09:19 PM
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It's a commercial Zastava Mauser action, with a 7x57 barrel. By good fortune, I found a new Zastava #1 contour barrel to put on it. Elk Ridge walnut stock. Just got it all put together. I think I'm going to really like it. Trajectory is almost exactly the same as a 30-06 with a 180 grain bullet, but the rifle is lighter than my -06, and the recoil is less.
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#4
10-16-2006, 07:51 AM
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FWIW, my 7x57 and my friend's both like H414 powder, although that's with a 140 grain bullet.
Great caliber- very effective at any reasonable range, and it doesn't kick you to death and make you deaf 
__________________
“May we never confuse honest dissent with disloyal subversion.” Dwight D. Eisenhower "If the freedom of speech is taken away, then dumb and silent we may be led, like sheep to the slaughter" George Washington Jack@huntchat.com
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#5
10-16-2006, 10:43 AM
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Thanks for the tip. H414 might well be a better choice for the 150 grain load. If I get a reasonably warm, sunny day, I might get a chance to run pressures on H414.
Yes, I think the 7x57 is a great caliber, for all the reasons you give. It just seems to be a happy marriage. I think my 7x57 is going to become my main "go-to" rifle for hunting.
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