Help With First Ladder Test 6bra

[Ccrider]

I recently shot for my first time at 525 yards. 6bra Defiance drop port, 103gr Bart Hammers, H4895, 205m primers.

I was overwhelmed by the conditions starting out. The mirage was bad; you had to dial the scope back to 25-35x to see the target and the sun was directly in our face. The wind was 5-10 mph and was switching right to left and then a tailwind. This was manageable as the right to left condition was generally holding long enough to get three shots off.

I set up the ladder with .02 increments from 29.8 to 31.2 using Lapua brass. I also had some Alpha brass that I initially worked the load up with that I wanted to compare.

I was so concerned with trying to get comfortable that I forgot to check my LabRadar for the first three groups. My point of aim was 12 o’clock on the 9 ring, except for the one group I shot with the Alpha brass. I used the bullet hole at 6 o’clock on the 9 ring for that group.

Should I reshoot the ladder again to see if it repeats? Or, should I try to focus on a particular area.




Additional information: I spent a good bit of time working up the load at 100 yards with the Alpha brass. This barrel shoots best into the lands at 100 between 30.2 and 30.5gr.


Thanks for your help.

Charles

 

[22BRGUY]

I looks like 30.2 or 30,3 had the least amount of vertical stringing. I'd try in there with
a bit of seating depth changes

 

[swimster]

At 525yds. There is not much vertical change between 30.6 and 31.2 even if the avg. velocities vary 37 fps on 4 different charge weights. Could this be a barrel harmonic sweet spot? I think i would shoot those again.

 

[Ccrider]

At 525yds. There is not much vertical change between 30.6 and 31.2 even if the avg. velocities vary 37 fps on 4 different charge weights. Could this be a barrel harmonic sweet spot? I think i would shoot those again.

That makes sense. What throws me is the 31.0 group that seemed to break out. If that group had fell in with the others, the ladder would make sense to me. At the time, I felt good about the shots and did not see any condition that would have caused it.

In reflection,I am wondering if I may have missed something on the conditions or with the load preparation. The avg velocity of 2956 was off from what was expected (2970+) and seemed bizarre, even though the 18 es was not horrible.

 

[JFrank]

I see two nodes on this particular day..
On your first target, ( 525) I suggest 30.2 is the middle of a .3 gr node at 2920ish and 30.8 is the middle of the upper .3gr node at 2960 ish.

Just me of course

 

[CharlieNC]

I see two nodes on this particular day..
On your first target, ( 525) I suggest 30.2 is the middle of a .3 gr node at 2920ish and 30.8 is the middle of the upper .3gr node at 2960 ish.

Just me of course

Me too. And the nodes are 3% apart, which appears to be normal for these types of ladder tests!

 

[shoot4fun]

@Ccrider With all we had against us at the 525 yard range that day I would suggest not putting a lot of stock into that target for load development. After all, it was your first time at that distance and between the little swirl of wind conditions, sun directly in our faces and target in full shade you stood up well to stuff many seasoned long range shooters have difficulty handling. I was very impressed.
I guess I'm saying we need another range day.
Looking at both the 525 and 100 yard groups I see possibilities between 30.2 and 30.6 in Lapua brass. I also think you have your seating depth correct for that powder charge range.

 

[Danley]

For Brock's Gap, especially in the middle of the day, none of those are bad groups. I'd bet that the 31.0 was the wind doing it's typical thing there!

 

[swimster]

That makes sense. What throws me is the 31.0 group that seemed to break out. If that group had fell in with the others, the ladder would make sense to me. At the time, I felt good about the shots and did not see any condition that would have caused it.

In reflection,I am wondering if I may have missed something on the conditions or with the load preparation. The avg velocity of 2956 was off from what was expected (2970+) and seemed bizarre, even though the 18 es was not horrible.

The 31g group did scater but the group center was still close to the others. May have been bad conditions.

 

[Ccrider]

@Ccrider With all we had against us at the 525 yard range that day I would suggest not putting a lot of stock into that target for load development. After all, it was your first time at that distance and between the little swirl of wind conditions, sun directly in our faces and target in full shade you stood up well to stuff many seasoned long range shooters have difficulty handling. I was very impressed.
I guess I'm saying we need another range day.
Looking at both the 525 and 100 yard groups I see possibilities between 30.2 and 30.6 in Lapua brass. I also think you have your seating depth correct for that powder charge range.

Thanks @shoot4fun. Best time I have had shooting thanks to you. Can’t wait to go again. It is in one thing to read about mirage, quite another to shoot through it at long distance for the first time. I was really worried about possibly shooting the camera.

 

[Ccrider]

For Brock's Gap, especially in the middle of the day, none of those are bad groups. I'd bet that the 31.0 was the wind doing it's typical thing there!

Could have been and I missed it. The velocity for that group is off. Makes me wonder. I did not clean the barrel so at that point I had 24 shots down the barrel. Probably not enough to matter but I normally clean after 15 shots or less.

 

[Jet]

Don't underestimate your ability and overestimate the conditions. You have very useable data. Select 30.8 and do a seating depth test. Once you get the seating down go back and shoot another ladder in .14gr increments between 30.6 and 31.4.

Good Shooting

Rich

 

[Ccrider]

Don't underestimate your ability and overestimate the conditions. You have very useable data. Select 30.8 and do a seating depth test. Once you get the seating down go back and shoot another ladder in .14gr increments between 30.6 and 31.4.

Good Shooting

Rich

Thanks. I will fine tune the seating depth and then shoot another ladder.