Unexpected Ladder Test Results

[HuntClub]

Shot 2 groups of 5 today. One group was neck size only (Top); the other full length size (Middle). Was very surprised at the neck size only group.

load was 140 Accubond, Varget @ 40, 40.5, 41, 41.5, 42

The 40 grain load is the left outer most in both groups. The neck size 40.5-42 are practically on top of each other.

Thought, good, bad, suggestions appreciated.

 

[ckaberna]

In a node?

 

[eric32]

Distance ladder test shot at

 

[Sniper338]

You shot too close. You need to extend the distance to past 200 yards at least and try again.

What your seeing is a 100 yard ladder test that is shot too close to really be able to tell anything.

Correct me if Im wrong, but thats just a guess by the looks of everything.

 

[HuntClub]

You shot too close. You need to extend the distance to past 200 yards at least and try again.

What your seeing is a 100 yard ladder test that is shot too close to really be able to tell anything.

Correct me if Im wrong, but thats just a guess by the looks of everything.

This was a 100 yard range - that is what I am limited too. Found it very interesting that the FL cases (5 shots - bottom) opened into a circular pattern and the Neck Sized (top) only cases were all on top of each other. The lowest point on the bottom target was the 41 grain load - and it is a very close match to the 41 grain load on the top target - so is the 41.5 load. I am going to focus there first but did not expect to see such a close group as picture in the top target.

 

[eric32]

With a 100 yard limit on your range. Read Erick Cortina OCW method it will yield the best results

 

[seymour fish]

This was a 100 yard range - that is what I am limited too. Found it very interesting that the FL cases (5 shots - bottom) opened into a circular pattern and the Neck Sized (top) only cases were all on top of each other. The lowest point on the bottom target was the 41 grain load - and it is a very close match to the 41 grain load on the top target - so is the 41.5 load. I am going to focus there first but did not expect to see such a close group as picture in the top target.

Hunt, you have a node across 1-1/2 gr of powder. Excellent powder choice for your combo. Neck-sized , if previously fired in your chamber, will have more volume than full length sized, thus bit less pressure, and some neck tension differential playing into it. Exactly what a good ladder shows. Take the middle third of the node and ladder it in 0.1 grain increments, neck sized, at max distance you intend to shoot, or at 100 if it's all you got. Seymour

 

[John Russell]

"One group was neck size only (Top); the other full length size (Middle). Was very surprised at the neck size only group."

It does not surprise me at all. I only FL size if the case is too tight when closing the bolt, and for most of my accuracy rifles, I don't even own a FL sizer.

Short range bench shooters FL size because they don't want their rifles to roll in the bags... if you are not burdened with that requirement, then enjoy the advantages of neck sizing - accuracy and loooooong case life.

 

[Zero333]

Did you measure how far you the shoulder was bumped when FL sizing ?

 

[Alex Wheeler]

Wouldnt let that steer me to neck size. The most accurate rifles and groups in the world are shot with fl sized cases. Ladders at 100 are useless. Believe it or not you do not want a ladder thats small. You want to see each charge climb and settle out. I have shot 15 shot ladders at 1k that were under 6" total. That kind of ladder is bad, youll never make that combo work. Change powders or bullets until you see each charge climb and stop.

 

[seymour fish]

Wouldnt let that steer me to neck size. The most accurate rifles and groups in the world are shot with fl sized cases. Ladders at 100 are useless. Believe it or not you do not want a ladder thats small. You want to see each charge climb and settle out. I have shot 15 shot ladders at 1k that were under 6" total. That kind of ladder is bad, youll never make that combo work. Change powders or bullets until you see each charge climb and stop.

Bullshit

 

[HuntClub]

Wouldnt let that steer me to neck size. The most accurate rifles and groups in the world are shot with fl sized cases. Ladders at 100 are useless. Believe it or not you do not want a ladder thats small. You want to see each charge climb and settle out. I have shot 15 shot ladders at 1k that were under 6" total. That kind of ladder is bad, youll never make that combo work. Change powders or bullets until you see each charge climb and stop.

So, I can buy factory ammo and sight in at 100 yards...then take a deer at 450 yards with one shot...from the same gun sighted in at 100 yards....but i can't reload and achieve the same results because I didn't watch the bullet "climb and settle out" for 1k yards? OK.

 

[Alex Wheeler]

Good luck to you both. Looks like you have got it all figured out.

 

[dbramley]

Wouldnt let that steer me to neck size. The most accurate rifles and groups in the world are shot with fl sized cases. Ladders at 100 are useless. Believe it or not you do not want a ladder thats small. You want to see each charge climb and settle out. I have shot 15 shot ladders at 1k that were under 6" total. That kind of ladder is bad, youll never make that combo work. Change powders or bullets until you see each charge climb and stop.

Hey Alex,
I just shot a ladder with a shehane that had 21 shots over 7 different loads, total vertical was 6". As you know I shoot F-open so holding 5" of vertical over 20 shots if plenty good enough. However I am forever in a quest for knowledge so would you please explain to me why a "short ladder " is bad. I need to be enlightened. If you want, PM me or send me an email. dbramley@yahoo.com

Regards,

Dan

 

[seymour fish]

Bullshit

Alex, stop and think for a minute. Hunt, the OP, gave you some clues in his original post which you missed. First, his handle is Hunt. Second is "Accubond". Do you imagine he is shooting a 1K bench gun ? Do you imagine he has access to a custom FL die ? He has found a node, the center of which is likely to be very useful across wide temp variations in a Hunting scenario. A 140 Accubond is a 400-500 yd Hunting bullet, beyond which the bc thus wind sensitivity would preclude ethical hunting. He could simply chrono the center of his node, run it through a ballistics program, and hunt with it to his hearts content. Predict he would find 1/2 to 1 MOA accuracy at his max Hunting distance, which is adequate. As to your statement that 100 yard ladders are worthless, I disagree. They are an excellent first step. As to your wanting a " taller" ladder, you have expounded on the virtues of positive compensation, a theory which I believe in wholeheartedly, and have suggested means to build rifles which exhibit such. Consider his rifle may not be one of those. As to " all the best are full length sizing", yes it seems so for the last 10-15 years, with custom dies. The answer to his query is simply case capacity differential between neck sized and fulllength sized with presumably off the shelf dies with unknown neck tension and shoulder setback. He might re-tune to that, and find a similarly workable node, after spending time and money, and be right back where he started. No need to rain on his parade. As for my "bullshit" remark, I apologise

 

[Alex Wheeler]

If your rifle does not make one large ragged hole at 100 yd shooting a ladder test it is not accurate enough to be tuned using the ladder method. We have to trust the the holes in the target. I think the op would be much better off shooting 3 shot groups.

 

[dmoran]

My questions to the OP's test would be:
1.a. How were the necks sized with the full-sized cases + die type?
1.b. How were the necks to the neck sized only cases sized + die type?
1.c. Was the neck tension used to both case sets identical? if not, how much variation?

2.a. How much were the shoulders bumped/headspaced to the full-sized cases?
2.b. How much difference in case headspace between the neck size-v-full sized cases?

3.a. What cycle was each set of cases on?
3.b. Were both sets of cases from the same Lot of brass?

To me, if those above aspects were not accounted for and held very closely of each other, the results were more then just neck size-v-full sized, that outcome could of been more affected by the other aspects.

Just my 2-Cents
Donovan

 

[HuntClub]

Hey, guys - I appreciate all of the input, both supporting and (maybe) not so supporting. I really did not mean to start an argument among the group. However, There are some things that make sense, and some that don't. I am shooting a Tikka T3 7mm08. It will be used for hunting. I want to find as accurate a load as i can. I did. It was not the Accubond anyway. My load is settled. Sierra Game King, 150 grain, RE15 - I full length sizee the brass - then I clean it, then i neck size it using Lee dies. Here is my result that I have repeated on five (5) different dates. Enjoy - I do!
View attachment 1014759

 

[Ringostar]

With hunting rifles and limited distance to test at. I've never had any luck trying a ladder test. What worked best for me was shooting round robin groups instead.