Vertical.

R

russell m

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I looking for some help on vertical. If I have straight up/down vertical I am assuming this is a load problem. If I have vertical up/down & slightly left/ right this may be a bad wind read problem. I have been told if the wind is RED that the bullet will be pushed left & up. A GREEN wind will push bullet right & down. Are my assumptions correct? russell m
 
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russell m said:
I looking for some help on vertical. If I have straight up/down vertical I am assuming this is a load problem. If I have vertical up/down & slightly left/ right this may be a bad wind read problem. I have been told if the wind is RED that the bullet will be pushed left & up. A GREEN wind will push bullet right & down. Are my assumptions correct? russell m
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your barrel being indexed improperly?
 
Russel

That is about it. In right hand twist barrels, a left to right tends to push bullets down, and a right to left tends to drive them up.
This does not always hold true. But when it does, and you are forced to hold off for conditions, you must be willing to compensate for what ever the condition is causing..........jackie
 
Yes, wind can cause vertical with a diagonal pattern...Have you tested the rifle in calm conditions or mild 3-5mph quartering winds, and had the same problem..?
If you have the vertical in mild conditions...adjust your seating depth further into the lands..about .003"-.005" and shoot 3 shot groups.
My favorite conditions for load developement is 70-80 degrees, cloudy overcast with quartering consistent (not switching) winds 3-5 mph...
 
Jackie what percentage of the time do you find yourself having to hold for the conditions I was talking about. russell m
 
Russell,

If you shot a group in a combination of left and right winds with a load that is tuned well the angle of the line created by the horizontal wind is quite shallow, maybe something in the 10 degree range perhaps. If the group was say 0.75 wide due to wind in both directions the vertical will not be more than maybe 0.25, something like that.

If you are getting a say 0.25 - 0.30 of vertical in a group that is wind effected out to say 0.30 - 0.35 you have a lot more vertical than a horizontal wind will cause. Of course you could have some other wind factor causing vertical like wind over a mound or dropping down off the range roof etc.

I don't want to sound like I am some authority here because I am not but it has been my observation that in good conditions if you have around 0.30 inches of vertical at 100 yards you are probably around 0.3 - 0.4 grains out of tune and around 0.25 inches of vertical can be pulled in with a load change of around 0.2 grains. Give or take. That assumes you have got the seating depth correct. Seems to me that it works best to start with say a 10 thou jam, tune the load and then tune the seating, powder usually having a bigger effect than seating if you had to have one right and the other wrong. Powder can give maybe half an inch of vertical even with the optimum seating while seating might only give say 0.25 if the powder is right.

Bryce
 
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eww It seems like I shoot great 3 shot groups but when I go to 5 shots I am spitting shots. I am also working on this. I thought I had things figured out but this new Krieger is giving me fitts. russell m
 
Bryce So you are saying if I have more than .035 of vertical with the wind I was talking about the problem is more than likely in the load. russell m
 
Yes, if you had 0.35 vertical purely as a result of the lift or drop created by a pure horizontal wind you'd have a group probably at least 0.75 wide and maybe more. Seems that is the case to me anyhow.

What are you shooting in the Kreiger ? I have messed with three now and something in the 30 - 30.5 grains range of N133 with 68 Ultra's at 20 - 25 thou longer than just touching seems to be a universally good load. I recall you were shooting Ultra's as well ??

At a lower window load around 29 grains a seating depth of 10 - 15 thou longer than just touching worked better than the greater jam preferred by the upper window load.

I recently have shot three Kreigers in two similar rifles and the above upper window load has worked well in all of them, 30.1 grains in fact, up to 30.4 on a cold morning.

Bryce
 
Russel

I am not talking about verticle that is due to the load being out. I am talking about verticle that is built into the condition.
As you know, at ranges such as Tomball and Denton, this can be a real head ache. I can see as much as one bullet holes worth from conditions that are reversed. That is enough to wreck an agg.
This is something you have to find out during the match. I have had times when it did not seem as prevalent. But if it is there, you need to figure it out.
Knowing how to anylize what the conditions are doing to the bullets can mean the difference in winning, and being in the middle of the page.......jackie
 
I'm going to go out on a limb here, but to say that .3 of vertical can't be caused by the wind doesn't fit my experience. It probably won't happen on a flat range, with no side berms or trees. But if the range isn't flat, and if there are berms & trees along the sides, you're going to have to figure out the range -- or try to.

For example, at Rockingham NC, I have seen the 30 and 60 yard flag ribbons blowing straight up, and for a longer period of time than would be caused by the momentum of a sudden gust. If you happen to shoot in such a condition, you'll get proof on paper.

But there are also conditions where the tails don't point straight up and yet a shot still goes high or low, and newcomers think they must have mis-handled the gun, or their load is wrong, or some such. Usually, that isn't true.

Wind effect analysis, as given in the books, seems to assume you're 100 feet up in the air. But the wind along the ground is like the water along the banks of a river. The water in the river will be flowing at a constant rate downstream, but along the banks, it can be doing all kinds of things -- including going the other way. The effects wind along a boundary condition are worse, because the force and direction are constantly changing. In a river, both the force (gravity) and direction are constant.

Shooting in a tunnel is one thing -- I'll buy that the vertical is due to the load, or maybe gun handling. But outside, on the range, it can also be the conditions.

FWIW
 
200 yard weather reports

Groups have been posted in the 2.5 inch range that are near 45 degrees to the horizontal plane. It's very typical...

Could be a load problem and hopefully it is. Seat the bullet touching the lands and find out where the max load lives in terms of safety, brass life and aggravation. Then reduce the powder to a tolerable level where the vertical is minimal.

In the meantime, start looking at the firing mechanism of your rifle. Consult a gunsmith that understands the finer details of the same.

BTW - what's that rifle made of?
 
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