What’s causing this group?

Zman99

Well-Known Member
Joined
Jul 25, 2016
Messages
78
I am trying to work up a load for the 180 Berger hvld in a 7mm rem mag. I shot a ladder at 660 yards and had 4 inches of vertical between 68.5, 69 and 69.5 of h-1000. I loaded up 69 grains and tested seating depth .010, .030, .050 and .070 off the lands. Tested at 300. .030 and .070 bot shot about 2.5 inches. It was fairly windy so I loaded up just the .030 and .070 off loads and tested them at 105 yds with no wind. Both shot .75 inches. The problem is I know this fun can shoot tighter. The groups show two touching and one off. It was the same for both seating depths. It happened the first time at 300 yards as well. At 300 yds there were two right next to each other and one 2.5 inches away. What would be your next step? How do I get the one round to suck in? Forgot to mention the order is 1st shot then 2nd one off and then the 3rd back touching the first. Attached are the 105 yard groups.
 

Attachments

LaHunter

Well-Known Member
Joined
Sep 30, 2012
Messages
501
Location
N.E. Louisiana
I may be off, but I was under the impression that you should be looking for less vertical spread than 4" at 660 yards while doing a ladder to really be confident that you were in a good 'accuracy node'. Hopefully other with more ladder experience will offer their opinion.
Also, while doing load development, I find it better to load 5 rounds at a given charge & seating depth. If I can put 5 rounds inside .5 moa, I have much more confidence in the load vs just 3 rounds.
Your 'flyer' may not be a flyer, it may just be part of your group with that load & seating depth. If you shoot 5 rounds, your .75 moa group may end up being 1 moa or larger.
FYI, the Berger vld type bullets can be more difficult to dial in. They tend to be less forgiving when it comes to seating depth. I listened to a podcast recently with Berger speaking about the vld vs their hybrid hunter bullets and seating depth.
Good luck
 

Jon Bischof

Well-Known Member
Joined
Oct 25, 2002
Messages
264
Location
Paragould, AR
The above advice from LAHunter makes sense to me because you stated that the order of your shots is 1st, 2nd off and the 3rd touching the 1st. That would be really perplexing to me and I would probably scrub my bore furiously with Barnes CR10 Copper Remover.
Maybe you should try the VLD at a different seating depth and see if you can get three that stay together. Yeah, that 1, 2 away from the flock, 3 with the 1st thing would bug the heck out of me; especially since 1 & 3 are so close.
 

Farmerboy78

Well-Known Member
Joined
May 23, 2018
Messages
453
Location
Arkansas
From my experience with Berger vlds, they like to be right against the rifling if not slightly jammed. In every rifle I shoot or have shot them in.
 

RT2506

Well-Known Member
Joined
Jan 10, 2008
Messages
2,009
As said three shots don't tell the whole story. That one out could come from MANY things. Just simple difference in the way you mount the rifle could cause this. Is the rifle capable of bug hole accuracy? It is a belted mag, is it head spacing off the belt or the shoulder? I could go on for a while. Good luck.
 

Coldfinger

Well-Known Member
LRH Team Member
Joined
Feb 20, 2020
Messages
406
Location
NY
I am trying to work up a load for the 180 Berger hvld in a 7mm rem mag. I shot a ladder at 660 yards and had 4 inches of vertical between 68.5, 69 and 69.5 of h-1000. I loaded up 69 grains and tested seating depth .010, .030, .050 and .070 off the lands. Tested at 300. .030 and .070 bot shot about 2.5 inches. It was fairly windy so I loaded up just the .030 and .070 off loads and tested them at 105 yds with no wind. Both shot .75 inches. The problem is I know this fun can shoot tighter. The groups show two touching and one off. It was the same for both seating depths. It happened the first time at 300 yards as well. At 300 yds there were two right next to each other and one 2.5 inches away. What would be your next step? How do I get the one round to suck in? Forgot to mention the order is 1st shot then 2nd one off and then the 3rd back touching the first. Attached are the 105 yard groups.
Story of my life. Get 2 in one hole then screw the third one. I thought it was me but replies to your question may enlighten!!
 

new2mud

Well-Known Member
Joined
May 3, 2010
Messages
200
Location
Heart of TX
This article is getting lots of attention lately:

The TL;DR summary is that you may want to try 0.090 and .110 off lands as well, if you are looking for a long-term forgiving jump (despte potentially not necessarily providing the tightest group for right now in your barrel’s stage of life.)
 

Beluebow

Well-Known Member
Joined
Dec 6, 2004
Messages
162
Location
Ar.
Did your ladder test consist of one shot at each charge weight listed?

Can you post a pic of your ladder test?
 

shphtr

Well-Known Member
Joined
Jul 7, 2006
Messages
216
Location
Alaska
I have had that same problem several times in the past .... always corrected with rebedding the action.
 

Beluebow

Well-Known Member
Joined
Dec 6, 2004
Messages
162
Location
Ar.
I don’t have pics of the ladder test. I shot 2 rounds each charge weight.
Your powder charge window isn't wide enough to gain any definitive information.

I would start over and widen the powder charge range if at all possible.
 

Trending threads

Recent Posts

Nightforce has great tracking capabilities, they are rugged, a bunch of elevation, holds zero forever, and reticles are designed for long range shooting. So if you are looking to shoot long distances constantly, then you need a scope that can take the abuse. -- gilmillan1


Culture Of Excellence At Nightforce Optics
By Len Backus

A high level of quality both in production and in service. Read More


Nightforce is such a solid combo of reticle, available elevation, glass that is good enough to shoot at the longest range you can dial. Nightforce has bullet proof construction that can handle the incidental horse rolling or some other rodeo action. -- bigngreen


Nightforce ATACR Scope Review
By Jeff Brozovich

The new NightForce ATACR is for sure a top choice for any long range shooter. Read More


The total package. Nightforce is the best I have used as far as turret feel and solid detents. I have never had one that didn't track right on and always return to zero. Nightforce NXS is the best value for everything I need. -- Broz


Nightforce Velocity 1000 Reticle Review
By Scott Shreve

I think Nightforce knocked it outta the park with this reticle! Read More

NightForce


Top