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Does VLD seating depth affect Velocity Standard Deviation?

I've never used VLDs before, so I am following the Berger method to find a good seating depth.

I have a Krieger barrel for my 6.5 creedmoor, and with previous bullets (ELD-Ms) I was able to get 10 shot SDs anywhere from 3 to 8 with my current load for ELD-Ms.

Being new to VLDs, I tried a seating depth of jam which was a bad test because the brass still had to grow. I had SDs for 4 shot groups (which to me is statistically insignificant) of: 5, 13, 14, 18, 21.

Tested today with once fired lapua brass, bumped .002. This time I had a seating depth of .079. My SDs were:
8 (for 5 shots)
17 (for 7 shots)
18 (for 7 shots)
12 (for 5 shots)

The above is about where my node is. I'm curious if standard deviation will get better if I find a better seating depth for the VLDs.
 
I've never used VLDs before, so I am following the Berger method to find a good seating depth.

I have a Krieger barrel for my 6.5 creedmoor, and with previous bullets (ELD-Ms) I was able to get 10 shot SDs anywhere from 3 to 8 with my current load for ELD-Ms.

Being new to VLDs, I tried a seating depth of jam which was a bad test because the brass still had to grow. I had SDs for 4 shot groups (which to me is statistically insignificant) of: 5, 13, 14, 18, 21.

Tested today with once fired lapua brass, bumped .002. This time I had a seating depth of .079. My SDs were:
8 (for 5 shots)
17 (for 7 shots)
18 (for 7 shots)
12 (for 5 shots)

The above is about where my node is. I'm curious if standard deviation will get better if I find a better seating depth for the VLDs.

Good question, Im sure you'll find your answer here. If your components aren't short you could do the test yourself.

Ive been finding my seating depth before I find the best powder charge and it's been working well for me. Adjusting your seating depth will affect the pressure of your cartridge.
 
I have shot alot of barrels with the VLD's. Basically in two cartridges, the 6 Dasher and 300 WSM. Every barrel I had liked them in the lands. I never worried as much about the ES as to what the target told me. I have had barrels where the ES was two or three and it shot vertical at 1000 yards. Another load where the ES was 10 to 15 would shoot 10 shots in four inches at 1000 yards. I never tested less then 400 yards and looked for little round groups. Matt
 
I have shot alot of barrels with the VLD's. Basically in two cartridges, the 6 Dasher and 300 WSM. Every barrel I had liked them in the lands. I never worried as much about the ES as to what the target told me. I have had barrels where the ES was two or three and it shot vertical at 1000 yards. Another load where the ES was 10 to 15 would shoot 10 shots in four inches at 1000 yards. I never tested less then 400 yards and looked for little round groups. Matt

What was the barrel contour on the barrel with 2-3 ES that had vertical stringing at 1000?

I'm wondering if heavy barrels depend less on positive compensation than light ones.
 
Good question, Im sure you'll find your answer here. If your components aren't short you could do the test yourself.

Ive been finding my seating depth before I find the best powder charge and it's been working well for me. Adjusting your seating depth will affect the pressure of your cartridge.
I have shot alot of barrels with the VLD's. Basically in two cartridges, the 6 Dasher and 300 WSM. Every barrel I had liked them in the lands. I never worried as much about the ES as to what the target told me. I have had barrels where the ES was two or three and it shot vertical at 1000 yards. Another load where the ES was 10 to 15 would shoot 10 shots in four inches at 1000 yards. I never tested less then 400 yards and looked for little round groups. Matt
What Matt said. The relationship is irrelevant. On target results are relevant. Not trying to be a wise guy but numbers don't win. Do not get fixated on them.
Thanks guys. I was pretty happy with the vertical but the SD was big.

This is a plot of my shots. I think I found a good velocity node. My horizontal wasn't very good though, although I ignored the 6-12 mph wind to keep consistent point of aim.

Y axis is the horizontal in inches from the center line of the target. X axis is velocity. This is for 4 charges. I'm wondering if different seating depths will make the SDs better...even though groups is more important than SD
 

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What was the barrel contour on the barrel with 2-3 ES that had vertical stringing at 1000?

I'm wondering if heavy barrels depend less on positive compensation than light ones.
Heavy varmint. I have ran into this with multiple barrels and also saw others have this. On Our heavies, we use a 1.450 straight. On our light guns, we usually use a light or heavy varmint depending upon weight. I believe it has more to do with bullet stability. Matt
 
I find that ES is influenced by powder, charge weight, and primer (in that order) than seating depth. My ES usually goes down as I approach a maximum charge, and some powders never give me a good ES. I use standard primers in .223 Rem, .284 Win, and 10 mm Auto, switching to magnums for .338 Lapua. I look for the best seating depth last in my load development.
 

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