Ladder test question and picture

[darkgun82]

Just finished my first ladder test. 308 at 300 yards on a new tv box. Rounds are marked and numbered. Shots 1 and 2 are extremly close, but 1-5 are all somewhat close. Should I perform the next test with 1 and 2 or 1-5? And is the second test ok to perform at 300 yards also. Back at my hunting area I could shoot for miles if I wanted. Here in Louisville the only range is knob creek and 300 is about the limit.

1st and 2nd shots are about 1" apart for reference

 

[vman]

Re: Ladder test question and picture

4-5 and 10-11 have little vertical from the looks of things.

I would do some further investigation into the small areas.

 

[Coletta]

Re: Ladder test question and picture

I would reshoot the ladder, and see if it stays consistent. Was the first shot fired from a clean barrel? Where all other shots from a fouled barrel? 1 and 2 may be more different than you think. If 1 was from a cold and clean bore, then I would reshoot 1 with a warm and fouled bore. Also, how long did you wait between shots?

 

[turbo54]

Re: Ladder test question and picture

The last two responses are correct.

Always run at least two identical ladders at a time....three if you've got the time/patience/focus.

 

[turbo54]

Re: Ladder test question and picture

Also: did you find the max load? If not, load another pair of ladders up, and go higher in charge. You wanna come home with unfired rounds.

 

[darkgun82]

Re: Ladder test question and picture

Vman....so little to no vertical difference is what I'm looking for?

As for the rest, I shot the rifle 8 times since last cleaning so first shot on the ladder wasn't a clean bore. I'd guess minute and a half to two minutes between shots. I'm not opposed to shooting another identical test just to verify my results and probably will do it again this weekend when I get a chance.

How many ladder tests do y'all do for each caliber/rifle?

 

[turbo54]

Re: Ladder test question and picture

My methodology is:

Two ladders run "round robin"
Bullets jammed into lands ~.005"
From a light/medium load to DEFINITELY over max - my aim is to find the max load.
Aim each shot like my life depends on it.
Come home, analyze data.
Load/fire an OCW test-bullets jammed
Tune seating depth by loading nodal groups of 5, in .010 increments.
Analyze data
Fine tune seating depth with groups of 5 in .005" increments.

Obviously, this process is aborted if my first OCW doesn't show goid accuracy. Try a new bullet or powder and start over.

 

[crewchef]

Re: Ladder test question and picture

turbo54 - just curious, why ladder and then OCW? My last load work up I went with OCW method and was happy with results. If mixing of the two offers some improvement over just doing one or the other I would certainly be interested.

darkgun82 - yes for ladder test you are looking for vertical grouping results that indicate "nodes". You can then work up new test loads using smaller incremental charge weights around those nodes to fine tune.

 

[turbo54]

Re: Ladder test question and picture

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Crewchef</div><div class="ubbcode-body">turbo54 - just curious, why ladder and then OCW? My last load work up I went with OCW method and was happy with results. If mixing of the two offers some improvement over just doing one or the other I would certainly be interested.

darkgun82 - yes for ladder test you are looking for vertical grouping results that indicate "nodes". You can then work up new test loads using smaller incremental charge weights around those nodes to fine tune. </div></div>

The reason I do a ladder prior to an OCW is to:

1. Coarsely find potential nodes
2. Find max load for that bullet/powder/brass combination

I see an OCW as a finer test that tests for the nodal limits, not "where" the nodes are.

 

[Huckleberry75]

Re: Ladder test question and picture

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: turbo54</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Crewchef</div><div class="ubbcode-body">turbo54 - just curious, why ladder and then OCW? My last load work up I went with OCW method and was happy with results. If mixing of the two offers some improvement over just doing one or the other I would certainly be interested.

darkgun82 - yes for ladder test you are looking for vertical grouping results that indicate "nodes". You can then work up new test loads using smaller incremental charge weights around those nodes to fine tune. </div></div>

The reason I do a ladder prior to an OCW is to:

1. Coarsely find potential nodes
2. Find max load for that bullet/powder/brass combination

I see an OCW as a finer test that tests for the nodal limits, not "where" the nodes are. </div></div>

Before I even knew anything about what the tests were called this was pretty much my process as well. Seems like you get the best of both practices this way.

Plus 1 for this method. It has always served me well.

 

[Coletta]

Re: Ladder test question and picture

You are gonna have to buy like ten more tv's now.

Post your results again.