Horizontal Dispersion

BCBRAD

BCBRAD

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Location
Prince George BC
As a prelude, I've been shooting long range for about 5 years now ( been handloading and shooting/hunting for 35yrs +).

I can keep, under good conditions, 0.4 - 0.75 moa at 1048 yards for 5 shots and ~1 moa for 10 shots.

What is killing my groups is horizontal dispersion. To that end new bags and front rest were purchased, out this am with next to no wind at 200m, and that horizontal is still there (BTW the rifle and load has gone 5 1/16" at 1048 yds in practice). I realize that it will take some practice with the new bench set up.

Does anyone in the long range community have any 'tips' I can work on to reduce this problem?

https://lh3.googleusercontent.com/p...?key=NWJNcHZmdTNkYUp4RHVuaGluWV8ydFhQeDhORVJn

200m/219yards
 
Shoot 5X5rds groups.. if the average continues to be wide and you have done all to tune the load and shoot under calm conditions...

time for a new barrel...

IMG_1990.jpg

New barrel, less then 40rds fired when these groups were shot... 200m is not that far out and given the gear you have, it should drill itty bitty groups.

Jerry
 

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^^^ This is with a 9 lb Tikka T3 with a #5 Benchmark barrel chambered in 6 Dasher, with ~600 rounds on it, Scope is a Sightron S111 6x24. Trigger is ~19 oz and rifle is bedded perfectly in the original stock.

This rifle and load (34.70gn H-4350, 105gn berger Hybrid) went 5 1/16" in practice and 7 5/8ths in competition
 
We always like to blame the equipment. I would take a look at your trigger control. Horizontal dispersion is usually a cause of inconsistency in trigger control and follow through.
 
kthomas said:
We always like to blame the equipment. I would take a look at your trigger control. Horizontal dispersion is usually a cause of inconsistency in trigger control and follow through.
Click to expand...
I watch the reticle closely while I grip, and can see that alone affecting left to right dispersion if I don't hold it just right. after that id keep a mindful eye on your cheek rest pressure and direction. after that id say trigger control isn't straight back. these have been the biggest contributions to my personal horizontal distribution.
 
BCBRAD said:
^^^ This is with a 9 lb Tikka T3 with a #5 Benchmark barrel chambered in 6 Dasher, with ~600 rounds on it, Scope is a Sightron S111 6x24. Trigger is ~19 oz and rifle is bedded perfectly in the original stock.

This rifle and load (34.70gn H-4350, 105gn berger Hybrid) went 5 1/16" in practice and 7 5/8ths in competition
Click to expand...

Why not Varget?

Which primer?

With this type of set up, at 200m, I would expect to be punching 1/2" 5 rds groups (1/4MOA). If the group you have pictured is some of the best this combo can do, I would be looking at first going to another primer, another powder.. then another bullet (Hybrid is not bad.. barrel may not like it).

I always assume you have flags and are watching them and the mirage.

1/2 to 3/4 MOA at 1000yds is reflecting the accuracy you are getting at 200m... you are doing a great job at being consistent in your shooting.

If you have tried all that you can and still have 1/2 to 3/4 MOA performance at 200m.....

Get another barrel.

Jerry
 
The equipment is so good these days, that I guarantee it's not the barrel. If it's the barrel, it would be causing vertical dispersion as well, not just horizontal. The group the OP posted is very indicative of human error. If it was the load or barrel, the gun would be exhibiting that at any distance, and not just 200M. There could be something mental going on between the two distances, or the OP just happened to be very consistent in his trigger control for the group he shot at 1048M.

I also highly doubt that the ammo is causing horizontal dispersion to that degree at 200M. If it was ammo, you would see dispersion on all the axis', and at all distances.

People never like to admit or bring up human factor when shooting. It always seems to stem back to equipment. If you go to any quality professional shooting training (such as many of the excellent US based ones), and you exhibit horizontal stringing in your groups - they are going to work on your fundamentals, particularly trigger control and follow through. 99 times out of 100 that will reduce the horizontal stringing.

Of course, someone who sells barrels is going to recommend a new barrel. But then the OP will have a shiny new barrel that still exhibits horizontal stringing. New equipment is not always the answer.

To the OP, some of the best money spent on this sport is on professional training. I've heard many iffy reports on the training schools in Canada, so if you can swing it, I would make a trip to Rifles Only in the US. Probably the absolute best money I've spent on this sport. They absolutely hammer in the fundamentals, which makes it a great first place to go for training. Pumps Precision Rifle Training and K&M are other great professional places that I've had the pleasure of training with.
 
Thanks, things to concentrate on ...trigger control probably should dry fire a few times as warm up to a group.

The Sightron has a dot, been using them for a few years and still not used to the dot swimming around, although my new bench bags and rest reduce this visually.

I use Varget in the other 6 Dasher with a 105gn Hornaday BTHP for banging steel and such, it is a 223 heavy barrel replacement as i find 223 tedious to load for.

I am pretty deep into QuickLoad so develop loads with that and a LabRadar. Varget does not model as well as H-4350. H-4350 hits all the markers for a good load.

I guess more focused practice is part of the message here, also the 105 Bergers are all gone so time to trial 105 Lapua's. I've always used CCI-450's due to there thicker cups. Federal SR's will pierce (btdt) , thinner cup and these are rebarreled Tikka's so the firing pin may not be just right for the small rifle primer.

I'm still listening.
 
kthomas said:
The equipment is so good these days, that I guarantee it's not the barrel. If it's the barrel, it would be causing vertical dispersion as well, not just horizontal. The group the OP posted is very indicative of human error. If it was the load or barrel, the gun would be exhibiting that at any distance, and not just 200M. There could be something mental going on between the two distances, or the OP just happened to be very consistent in his trigger control for the group he shot at 1048M.

I also highly doubt that the ammo is causing horizontal dispersion to that degree at 200M. If it was ammo, you would see dispersion on all the axis', and at all distances.

People never like to admit or bring up human factor when shooting. It always seems to stem back to equipment. If you go to any quality professional shooting training (such as many of the excellent US based ones), and you exhibit horizontal stringing in your groups - they are going to work on your fundamentals, particularly trigger control and follow through. 99 times out of 100 that will reduce the horizontal stringing.

Of course, someone who sells barrels is going to recommend a new barrel. But then the OP will have a shiny new barrel that still exhibits horizontal stringing. New equipment is not always the answer.

To the OP, some of the best money spent on this sport is on professional training. I've heard many iffy reports on the training schools in Canada, so if you can swing it, I would make a trip to Rifles Only in the US. Probably the absolute best money I've spent on this sport. They absolutely hammer in the fundamentals, which makes it a great first place to go for training. Pumps Precision Rifle Training and K&M are other great professional places that I've had the pleasure of training with.
Click to expand...

Thanks for that, I guess all my efforts so far have isolated the human part, worked on loads, bedding, quality barrels and gunsmithing, optics paying attention to installation...degreasing/torque etc.

Does anyone think a 19 oz trigger may magnify my errors?

I can pull off a good group once in awhile, but don't have the consistency required.
 
more horse power on the scope, yodave on the trigger.....

horizontal is either bag torque or wind, if you get it when there is no wind then it's torque
pull the rifle back on the bags and then push it forward, if your dot it no longer on the target then adjust your front rest windage, repeat the pull push until the rifle tracks back into the center of the target, load the rifle, deep breath, watch the dot, relax your breath and squeeze the trigger.....
 
Also I would make sure you are as square as possible behind the rifle, and using natural point of aim (NPA) to ensure you are not muscling the gun on target.

The gun will recoil in the path of least resistance, and will exploit any weakness you offer it. This can also cause inconsistency and dispersion from shot to shot.

Snipers Hide has some great videos on YouTube (if they are still there) and I believe their video content is moving to full30.com. They have a video subscription service which is very good if you like instructional videos. They have some great videos on the fundamentals and recoil. Rifles Only also has great training DVD's, which can be purchased on their website.
 
If anything, a light trigger masks poor trigger control. A heavier trigger won't be as forgiving.

Drives me nuts when I see videos of "professional"/shiny shirt PRS shooters slapping the hell out of their triggers, but they get away with it because they are running really light triggers.
 
I have a sneaky feeling, some don't quite understand the set up you are using for the bench rests. Or maybe, I am assuming things that may not be correct.

If you can post a pic of the front and rear rests, that will clear up some questions.

After all, you have done a very good job of isolating the rifle from the human part... so the human part is likely the cause of the problem :)

Jerry
 
20180619_081443_HDR.jpg

If you don't mind, thought posting the picture would make it easier to discuss.

First off, excellent front pedestal rest and rear bag set up. That should track very nicely.

Where I think you could have a bunch of trouble is in your stock and bag rider set up. Is there any wiggle in the parts? And I mean, you can move any part ANY amount?

Can you twist the rifle while the blocks are steady in the bag?

I assume the alum rider is attached to the stock through the swivel stud hole?

Ideally, you want the forend to be a single solid unit... the polymer stock can be a source of flex. Having a variety of parts not bolted and glued together can allow for flex.

If the front is solid, it may work the torque backwards to the stock infront of the receiver and so on.

If this were my rifle, I would build up the sides of the stock using plywood and polyurethane construction adhesive to make a rigid shape that fits the front bag precisely. Go from the rear of the action to the forend.

If you have access to milling machine, build up the forend with alum and bolt the whole thing together with glue. But I like the dampening of the plywood better.

It may not be the reason but it sure is a potential problem area and what I would investigate.

Jerry
 

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BCBRAD said:
https://lh3.googleusercontent.com/p...?key=SWhmb29ZUlNKN1BSUnQ5c0V6N254TUNveGZKaTVR

https://lh3.googleusercontent.com/p...?key=M3IySng5UUFZalV1VEs0LUE3NWZxdXROeU41Y2JR

This is a new set up for me, Sinclair rest and Edwards bag.

Previous set up was similar but not as refined or adjustable.
Click to expand...

you may wish to phone me...........I can walk you through it. It's not equipment or shooter error......it's purely in how you set up on the bench before you sit down to load one in the chamber........everyone thinks shooting from the bench is easy......LOL.....

PM me for number, or PM me yours and a good time to chit chat
 
Mystic Precision said:
View attachment 185559

If you don't mind, thought posting the picture would make it easier to discuss.

First off, excellent front pedestal rest and rear bag set up. That should track very nicely.

Where I think you could have a bunch of trouble is in your stock and bag rider set up. Is there any wiggle in the parts? And I mean, you can move any part ANY amount?

Can you twist the rifle while the blocks are steady in the bag?

I assume the alum rider is attached to the stock through the swivel stud hole?

Ideally, you want the forend to be a single solid unit... the polymer stock can be a source of flex. Having a variety of parts not bolted and glued together can allow for flex.

If the front is solid, it may work the torque backwards to the stock infront of the receiver and so on.

If this were my rifle, I would build up the sides of the stock using plywood and polyurethane construction adhesive to make a rigid shape that fits the front bag precisely. Go from the rear of the action to the forend.

If you have access to milling machine, build up the forend with alum and bolt the whole thing together with glue. But I like the dampening of the plywood better.

It may not be the reason but it sure is a potential problem area and what I would investigate.

Jerry
Click to expand...

Thanks for all. The 'adapter' is 3" wide as is the bag notch. It is screwed into the sling stud hole but also clamps to the sides of the stock and secured with screws. So there is little possibility of it wobbling around.

I will digest all information graciously given by the contributors and report back as I go through the information.

Again thanks.
 
Another thing to test and this is where your problem likely is...

Can you move the back of the rifle, like a rudder, with the front still? I bet you can and can likely move it a whole bunch.

You have a horizontal dispersion issue.... the stock can wag its tail....

If a scope is any indication, 1 thou of elevation cant on a basic scope set up leads to a 1" change in POI at 100yds

I bet you can cant and pan the rifle while the block is nicely held in the front pedestal.

Easy fix if that is the problem area.

Jerry
 
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