Vertical -- powder charge

[Link]

6br, 30gr Varget, I shot some 105 VLDs in a round cluster then shot some 105 custom bullets a friend makes that went vertical. Both a .600 group at 600 yds. Nothing changed except the bullets. I'm thinking a powder change is needed, if so how many grains do you think? Or maybe something else?

ty Don.

 

[mfendley]

According to Speedy - if I understand his graphic correctly, you want to go up .75 grains.

 

[gpoldblue]

6br, 30gr Varget, I shot some 105 VLDs in a round cluster then shot some 105 custom bullets a friend makes that went vertical. Both a .600 group at 600 yds. Nothing changed except the bullets. I'm thinking a powder change is needed, if so how many grains do you think? Or maybe something else?

ty Don.

I wouldn't change anything except the verticle turret on the scope....... both bullets with same load shoot the same size group. If the shapes of the 2 groups are different,then maybe a seating depth adjustment.

 

[Murray Brook]

You mean .6 MOA at 600, right

 

[jackieschmidt]

You mean .6 MOA at 600, right

^^^^^
I know a bunch of long range guys that would love to have this problem..

 

[G Liles]

If I ever shoot a .600 group at 600 I won’t be concerned with vertical!!

 

[Link]

You mean .6 MOA at 600, right

I'm sorry. I meant a .600 inch group at 300 yards. I must have had a dream,
a senior moment.

 

[BoydAllen]

I'm sorry. I meant a .600 inch group at 300 yards. I must have had a dream,
a senior moment.

Two different bullets might have shapes that are different enough so that identical charges would produce different pressures. For example, I have some Hornady bullets for my 6BRA that are about .1 farther into the case at touch than some of similar weight by another maker. I would expect that this difference would cause a significant difference in pressure (with the same charge) , which would affect tune. IMO you might consider upping the powder a little to round out the vertical group.

 

[rwj]

I'm sorry. I meant a .600 inch group at 300 yards. I must have had a dream,
a senior moment.

Still very respectable! Here’s hoping that @BoydAllen suggestion reduces the group size

 

[1shot]

If you shot two different bullets, and didn't change your B2O measurement, that could be your problem. If bullet "A" likes to be jammed, and bullet "B" likes to be jumped, the it isn't a fair comparison.
I hope this helps,

Lloyd

 

[Link]

If you shot two different bullets, and didn't change your B2O measurement, that could be your problem. If bullet "A" likes to be jammed, and bullet "B" likes to be jumped, the it isn't a fair comparison.
I hope this helps,

Lloyd

Both bullets were seated with a light jam. Maybe the 2nd bullet needs a depth workup?

 

[AlNyhus]

Bullets with different shank lengths are going to impart different 'vibration signal' to a barrel and also change the pressure. It would be amazing if there wasn't any 'on target' difference. -Al