OCW test

[[email protected]]

hello,

How many of you use the OCW test instead of a ladder test to find your load? I'm thinking about switching over to the OCW, what are the pro's and cons?

 

[1lnbrdg]

I usually use the Ladder to start with, then work OCW in smaller increments when I find likely nodes just to confirm and also get more data for each node area.

 

[okiefired]

I like OCW, the main reason is I think because it is a round robin test it makes the effects of barrel heating less likely to effect your results. They both can work well though.

okie

 

[[email protected]]

I like the ladder than OCW, I think I may just start with OCW at the higher end of the load data, than shoot round robin groups at 300 adjusting my seating depth to find the most accurate combo. That won't screw up my OCW parameters right?

 

[Bob 964]

Because you are only shooting 1 round at each charge weight, there are too many factors (e.g., wind, barrel fouling, trigger pull, etc.) that could negatively influence (skew) the results of a ladder test. For this reason, I prefer to use the OCW technique at a distance of 100 yards. This will factor out most of the wind effects, while providing data that is easily interpreted. Because the OCW technique uses 3-shot groups at each charge weight, taken in a round-robin fashion until you've been through all targets 3 times each, it spreads the error factor across all groups equally. You also get get 3 shots at each charge weight -- rather than the ladder test's one shot. So, if the barrel fouls and becomes inaccurate after 8 or 10 shots, the effects will be evident in all groups tested. This will yield more meaningful data, and is statistically superior to the conventional ladder test method.

 

[1lnbrdg]

What I like about the ladder test is it shows me the upper end and where pressure is an issue. I can throw away anything up in that range but I know where it is. OCW after that with node areas that look promising.

 

[gvanhyning]

I use the OCW because it drastically reduces trips to the range. I determine what my max load is using QuickLoad and work backwards. I build test shots at .2 to .3 grain increments. I have always found a charge weight that is grouping well at those increments. Once I have the charge weight I build the next test shots and increment the seating depth at .003". There is always a group or two that really stands out. I'll verify what I have out 1000 yards. I shoot all test shots through a chronograph. By doing this I know if the muzzle velocity is enough to go forward and can monitor ES and SD.