Help with new magneto speed numbers

I've got some tempilaq 750F but haven't tried annealing yet. I've been too worried about it not being consistent enough with the drill and torch method. You think doing that would be more worthwhile than using the federal brass?
Absolutely, don't worry about the tempilaq, put it in the socket spin it up and count to six or seven, just do the same thing every time and you'll be fine
 
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I've got some tempilaq 750F but haven't tried annealing yet. I've been too worried about it not being consistent enough with the drill and torch method. You think doing that would be more worthwhile than using the federal brass?

Yeah, if you switch to federal you will probably have to rerun the test you have done so far. The node will probably shift a bit. I would attempt annealing and continue your testing. Use a 9/16" socket and drill adapter in a drill to spin the case in a propane torch flame. Aim the flame at the neck/shoulder junction. Instead of templiq, I annealed in a blacked out dark room and watch for just the very slightest hint of glow in the neck. Better under than over til you get the hang of it. Dump into a metal pan to cool.


I have since switched to an AMP machine. I can tell you though the increase in quality between annealing and not annealing was much greater than the change I saw between torch in a dark room annealing and using the AMP.
 
i have one of the torch type wheel ones . wanna borrow it ???

Thanks for the offer!! I sincerely appreciate it. I may have to pass though and just give the torch and drill a shot. I definitely don't want to end up convincing myself to buy another piece of equipment haha. I need to save that money for a neck turning tool ;) did you get out to shoot over the weekend? I ended up going very last minute and only had an hour before close.
 
Yeah, if you switch to federal you will probably have to rerun the test you have done so far. The node will probably shift a bit. I would attempt annealing and continue your testing. Use a 9/16" socket and drill adapter in a drill to spin the case in a propane torch flame. Aim the flame at the neck/shoulder junction. Instead of templiq, I annealed in a blacked out dark room and watch for just the very slightest hint of glow in the neck. Better under than over til you get the hang of it. Dump into a metal pan to cool.


I have since switched to an AMP machine. I can tell you though the increase in quality between annealing and not annealing was much greater than the change I saw between torch in a dark room annealing and using the AMP.

That's good to know! I assume it's mostly just from the different case capacity? If it makes that big a difference, how big a difference does the headspace make for a given brand? For example, my Winchester brass with one being 0.001 from case shoulder to chamber shoulder and another being 0.004? If i anneal some cases, I've got a plethora of 4x Winchester brass, so I should be able to continue testing with the same brass until I'm satisfied with my results. But some of them may need the shoulders bumped back versus just neck sized... Measuring ALL of those to make sure they're all identical from base to datum would take me a bit.
 
Well here's what I've got. I'm not sure what to make of it. Maybe there's a node somewhere between 60.6 and 61.2? Then another starting around 63.0?

BTW, 63.0 is book max from Hodgdon's web site, so I didn't load any passed there. But, I saw no pressure signs on those rounds, so I may load a a few at 63.3 next time.


chargeshot 1shot 2
6027552876
60.329402901
60.629022913
60.929402934
61.229272918
61.529522978
61.829302970
62.129772942
62.430072959
62.729523020
6330303036

And I've also attached a picture of the graph. Using the extra rubber spacer on top of the barrel worked pretty well.

Also, I noticed a lot of blast dimples on the sensor. Has anyone else had this happen? I'm wondering whether it is just from the blast or if it's unburned powder. Here's a picture.
If you look at the deltas between the averages looks like you have a nice node across shots 8-10. That 63 is a pretty big jump point. I'd shoot 62.8 and 63.9 to find the actual jump point. Or you could just load 62.5 or 62.6 and go for groups.


chargeshot 1shot 2AverageShot SequenceDelta
60​
2755​
2876​
2815.50​
1​
60.3​
2940​
2901​
2920.50​
2​
105.00​
60.6​
2902​
2913​
2907.50​
3​
-13.00​
60.9​
2940​
2934​
2937.00​
4​
29.50​
61.2​
2927​
2918​
2922.50​
5​
-14.50​
61.5​
2952​
2978​
2965.00​
6​
42.50​
61.8​
2930​
2970​
2950.00​
7​
-15.00​
62.1​
2977​
2942​
2959.50​
8​
9.50​
62.4​
3007​
2959​
2983.00​
9​
23.50​
62.7​
2952​
3020​
2986.00​
10​
3.00​
63​
3030​
3036​
3033.00​
11​
47.00​
 
That's good to know! I assume it's mostly just from the different case capacity? If it makes that big a difference, how big a difference does the headspace make for a given brand? For example, my Winchester brass with one being 0.001 from case shoulder to chamber shoulder and another being 0.004? If i anneal some cases, I've got a plethora of 4x Winchester brass, so I should be able to continue testing with the same brass until I'm satisfied with my results. But some of them may need the shoulders bumped back versus just neck sized... Measuring ALL of those to make sure they're all identical from base to datum would take me a bit.

It might, or it might not. Weighing the cases might give you an idea of the difference in capacity between case manufacturers. Only way to know for sure is to test it. Best bet is to continue with the same manufacturer you have been using, until you have your load established. After that, you can swap to another manufacturer and adjust your charge to get back into the best part of the node.
 
If you look at the deltas between the averages looks like you have a nice node across shots 8-10. That 63 is a pretty big jump point. I'd shoot 62.8 and 63.9 to find the actual jump point. Or you could just load 62.5 or 62.6 and go for groups.


chargeshot 1shot 2AverageShot SequenceDelta
60​
2755​
2876​
2815.50​
1​
60.3​
2940​
2901​
2920.50​
2​
105.00​
60.6​
2902​
2913​
2907.50​
3​
-13.00​
60.9​
2940​
2934​
2937.00​
4​
29.50​
61.2​
2927​
2918​
2922.50​
5​
-14.50​
61.5​
2952​
2978​
2965.00​
6​
42.50​
61.8​
2930​
2970​
2950.00​
7​
-15.00​
62.1​
2977​
2942​
2959.50​
8​
9.50​
62.4​
3007​
2959​
2983.00​
9​
23.50​
62.7​
2952​
3020​
2986.00​
10​
3.00​
63​
3030​
3036​
3033.00​
11​
47.00​

can you please explain this delta addition you added and how it applies to a node . in my train of thought, those shots at 8 9 10 was a very unstable area .that id steer away from ??
help me make it make some sense .
 
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can you please explain this delta addition you added and how it applies to a node . in my train of thought, those shots at 8 9 10 was a very unstable area .that id steer away from ??
help me make it make some sense .
I just did an average of your 2 shots at each charge load. Then I took the Delta's between the averages to see how many fps the averages varied step to step. It's just some simple analysis to smooth out the data even though 2 shoots are not a huge sample it's what you had. If you do this you can easily see the big velocity jumps.

Remember using any chronograph is not an absolute end result. Thats why when prepping to verify a velocity you should shoot 10 or 15 rounds and take the average as a starting point, then shoot long range requiring various correction to verify your average. Usually there is a little more velocity adjustment at that point as well. This is because chronographs get you in the ball park.
 
I tried some annealing with my drill and torch and I did almost 60 cases in half an hour. After smoking a couple to get the torch in the correct position and get the timing down, it was pretty easy.

I tried using the tempilaq on the inside of the neck on the first couple of sacrificial cases, just because I had it on hand, and it wasn't helpful. The cap on my bottle was broken, unbeknownst to me, possibly from falling off a shelf. So the tempilaq was somewhat separated and gloopy. I tried shaking it to homogenize it but it didn't work out very well. On top of that, since my drill wanted to spin to quickly and there's carbon in my necks, I couldn't actually tell when the stuff liquified.

So I just turned the lights off and tested a couple cases going until I could just barely see a color change in the dark and set my timer for that time.

I tested a few by using a pair of pliers to gently squeeze the dead soft ones, the unannealed ones, and the good annealed ones for comparison in their hardness/springback.
 
ryan.. thats gonna do you good .. i bet just annealing will drop your es .. cant wait to see the number change the the same brass
the other thing that i think make a difference would be to pre-expand them prior to seating to try to keep the gripping spring back a little more equal
 
Here are some more numbers:


chargeshot 1shot 2shot 3shot 4ESSD
60.629052932291229272713
60.82918292529242912136
6129342929296229423315
61.22972295329542953199
633017299429516634
63.13025302430421810
63.2303330303040105
63.33008303330262513


I think there's a couple outliers in there due to issues I was having with my die which probably resulted in some inconsistent neck tension. Something I did notice, was that the case necks of 63.0-63.3 started looking a little cleaner. All the case necks of the lower charges were still very dirty. I will have to do some more annealing to see if this makes a difference, but I think it's likely just needing to hit higher pressure to get a good seal. Next time, I'll test 60.8, 61.0, and 63.2 for groups.

On this batch of brass, it was only neck sized and at it's maximum base to datum length. I'll have to bump the shoulders back before the next session. If my FL die is set to bump the shoulders back by 0.003, how will this affect my known velocity nodes and associated charges? Will I need to increase the charge by something like 0.1gr to hit the same velocity node since some of the pressure build will be going to stretching the brass?
 
I can't say for sure, but I wouldn't adjust the charge weights any. I also wouldn't bump the shoulders back unless you have a hard bolt close on an empty case. As long as the case fits and the bolt closes easily, I'd neck size only. My prediction is your 63.2 group will be the best.
 
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