Chrono OCW analysis?

[Zack_va248]

Thoughts? Case pic is the lowest charge on the left and the highest on the right. Bighorn TL3 Action so it leaves that crater around the firing pin dent all the time. Never felt a difference in bolt lift. Avg graph tells me 41.3g but the separate string graph is looking like 41.1-41.2. Anyone else see anything different or suggestions to what else I should test? I’m thinking I’ll do another ladder from 41.0 to 41.6 in .2 increments and 5 rd groups just to fine tune it and have a better sample size. Targets shot at 100 yds.

Hornady brass x1 fired
CCI 200
140g eld
All seated .060" off the lands

 

[Dthomas3523]

41.1 or 41.2

Dial in seating depth and done.

 

[Jordanwickham]

You are confusing two different load development procedures. You've effectively done a Saterlee test and for some reason shot it at a target as if it were an OCW test, then called it an OCW test.

 

[Zack_va248]

You are confusing two different load development procedures. You've effectively done a Saterlee test and for some reason shot it at a target as if it were an OCW test, then called it an OCW test.

Yes instead of shooting rds into a bank, I figured corroborating the data gathered by the chronograph with poi relativity to poa would support my findings. I also fired three rds at each load to get a better sample than one shot at each like the 'Saterlee" method suggests.
A 'Saterlee' test is still just finding optimal charge weight; using strictly info from the chrono to validate the nodes. They all are simply finding the widest range of powder loads with minimal velocity deviation. Label it whatever you want, the outcome is the same correct?
Wouldn't using as many inputs as possible provide the most accurate outcome?

 

[Jordanwickham]

Yes instead of shooting rds into a bank, I figured corroborating the data gathered by the chronograph with poi relativity to poa would support my findings. I also fired three rds at each load to get a better sample than one shot at each like the 'Saterlee" method suggests.
A 'Saterlee' test is still just finding optimal charge weight; using strictly info from the chrono to validate the nodes. They all are simply finding the widest range of powder loads with minimal velocity deviation. Label it whatever you want, the outcome is the same correct?
Wouldn't using as many inputs as possible provide the most accurate outcome?

I got cha. You are doing a lowercase optimal charge weight test.
In my experience with Saterlee and OCW, yes you end up at the same place but not at the same time unless you are using a LabRadar or good quality stand alone chronograph.
I don't know what kind of chronograph you used here but there also seems to be a bit of shooter induced on the paper target. I feel like the 41 charge was shot lower than it should have been based on the charge above and charge below.
I do think more data points give you the best results with one thing at a time. Too many error inducing variables gets things all jumbled up. Case in point the chronograph shows a definite node around 41-41.3, if you look at the paper target you would not go with 41-41.3 because the POI is quite different.

Is 60k jump mag length or why did you start there?

 

[308pirate]

I’m thinking I’ll do another ladder from 41.0 to 41.6 in .2 increments and 5 rd groups just to fine tune it and have a better sample size.

That's exactly what I would do, and I would then lock it down in the middle of the node.

 

[Zack_va248]

I got cha. You are doing a lowercase optimal charge weight test.
In my experience with Saterlee and OCW, yes you end up at the same place but not at the same time unless you are using a LabRadar or good quality stand alone chronograph.
I don't know what kind of chronograph you used here but there also seems to be a bit of shooter induced on the paper target. I feel like the 41 charge was shot lower than it should have been based on the charge above and charge below.
I do think more data points give you the best results with one thing at a time. Too many error inducing variables gets things all jumbled up. Case in point the chronograph shows a definite node around 41-41.3, if you look at the paper target you would not go with 41-41.3 because the POI is quite different.

Is 60k jump mag length or why did you start there?

magneetospeed v3 chrono. Definitely some shooter induced due to mirage. I was magged out to x10 and still had significant poa wiggle. position was good but the target in constant motion made it tough to discern that my poa was identical shot to shot. I quartered as best I could in the conditions.40- 60K was a seating depth range that was tolerant of lands eroding on Mark Gordons testing so I figured why not try it.

 

[Jordanwickham]

magneetospeed v3 chrono. Definitely some shooter induced due to mirage. I was magged out to x10 and still had significant poa wiggle. position was good but the target in constant motion made it tough to discern that my poa was identical shot to shot. I quartered as best I could in the conditions.40- 60K was a seating depth range that was tolerant of lands eroding on Mark Gordons testing so I figured why not try it.

Ok yeah I figured it was Magnetospeed. So really the target is just for visual. Can't really glean anything from targets with the Magnetospeed. I'd try like the others said and seating test at the velocity node and hope not much changes. If you are a ways away from your seating node your velocity will change. Not a massive amount but some.