Losing shots low.

[CZ550]

I have noticed i have been dropping shots low. I am pretty sure it's a flaw in my setup and trigger pulling and not load related because I never get any fliers that are high. I am running a Sinclair gen 3 bipod and rear bag. Today I shot a 10 shot group @ 400 that would have been 1/2 moa or better only to drop three of them several inches low. It has happened many times with several different bullet and combos. Anyone know of common causes ?

Thanks in advance.

 

[markr]

Possibly a bedding issue?

 

[CZ550]

I thought about that, however I just bedded this action into a T5a manners and I am pretty confident it is good to go. It doesn't sling shots around like it's a bedding or seating depth issue. If I lose a shot it always be low I can't remember ever slinging one above my aiming point not in the last 500 rounds I have fired anyways.

When I say low I mean 2 to 4 inches below the group @ 600.

 

[mr45man]

Is there any "play " in the bipod front to back?
if so and you do not load the legs the same each time, may cause verticals
John H.

 

[CZ550]

If the elevation adjustment is not screwed up all the way up or down there is a lot of slop in it. Not real happy with the design myself.

 

[Keith Glasscock]

Yup, you are probably pushing the gun with your shoulder or head. It changes the point of impact by not allowing the bipod to jump up as much. The other possibility is that you are lifting your head just as the rifle fires - where your head goes, your shoulder goes, and the buttpad goes too.

As much as I want to semi free-recoil my sinclair bipod, it just doesn't work. I get vertical flyers (low). Try giving the stock a little pull into the shoulder and make certain that you don't load the bipod. Really concentrate on seeing what the crosshairs are doing during recoil (it doesn't matter what they do, just that they do the same thing every shot).

I am not entirely certain that it is your technique though. The worst I can do at 300 yards is about 3/4 MOA change in POI from doing everything right to everything wrong. The low shots could be something else. I would shoot it again from the bench to see if the rifle is performing. I just got done chasing my tail and figured out that the barrel had gone south. I was starting to think I didn't know how to shoot any more until I put the rifle on the bench and used a proper setup just to find exactly the same problem I had prone. It would shoot 5 shot groups into 1/2MOA, but would start throwing flyers after that.

 

[Leaddog]

I've seen at longer ranges that a bullet will drop low when a cloud casts a shadow over the range during a string of fire.

 

[CZ550]

When u speak of fliers they are going everywhere correct ? If it was an accuracy issue like the barrel or load wouldn't the fliers go high and low.

This is a factory barreled action in .223 (Tikka). I have been planning to rebarrel, but the darn thing acts like it wants to shoot. It's no custom but I think it's 1/2 MOA capable out to 5 or 600 if I can get a handle on it.

 

[6BRinNZ]

CZ550 - does the chrony back up the assumption that its not load? Looking at the original post I would tend to agree that its not load, but sometimes it is useful to have anecdotal evidence to support a theory.

Would it be the same cases that are going low? Would it be the same shots within a string? How is paralax?

 

[CZ550]

I am embarrassed to admit I have not chronoed the load, time has been short and weather only cooperates for short period of time in the winter. As far as cases go I haven't kept track of brass or shots in the string.

 

[michaeljp]

I've noticed a similar thing happen with my 6PPC at 100m. I'd start a group of 5 with the first 4 almost in one hole and i mean 1 hole then the 5th shot will go low. This happened quite a few times. Then i noticed during neck sizing and seating that the neck pressure was different to the other cases. So during one session of reloading i paid particular attention to the cases that felt different during sizing and seating and put those cases aside. There were 6 out of the 25 cases. Well my groups shrank dramatically and when i loaded those 6 offending cases they did all shot to a lower point of impact than the others.

 

[Keith Glasscock]

To add to Charlie's post. Mirage can make the target appear to be higher than it is. If you are firing at a false target (high) and then fire at it again when the migage is done boiling, you can get "low" shots. I'll give the Op credit for already knowing that though...

 

[CZ550]

400 yard group two 3 shot groups. The lower three are the second group fired.

10 shot group @ 400 I wasnt holding for wind I wasnt concerned about windage.

Another 400 yard group. Not holding or paying attention to wind. The question mark is the dropped shot out of that group.

 

[CZ550]

Went out and shot 10 at lunch off of my front rest. No shots were dropped low, I had a couple that got away from me but they were at 11oclock.

Looks like I need to work on my technique with the bipod.

 

[in2deep]

Without windflags shooting at 400 yards is pretty tough to figure out an accurate load especially if it's a head or tail wind (like your groups look). Even small changes in direction or velocity over that much distance can cause shifts like you have but without doping wind the process can really drag out over many sessions as each variable has to be reduced.
Been there-done that. Testing long range loads on a nice calm morning=priceless.

 

[CZ550]

I would love to do all my shooting in calm conditions but I would never get anything done. Its rare for the stars to align and I have the available time when the condiitions are really calm. First thing in the morning doesnt work out to well for me most of the time.

I did shoot again today with a front rest, I am pretty confident that I need to work on my technique with the sinclair bipod. And I probablly need to tune the load a little. I will try to set the chrono up this weekend.

 

[Keith Glasscock]

Your technique might be some of it, but I suspect that you are a little out of the node or fighting something else as well. The 223 shouldn't be doing anything to the bipod, so I'm a little suspicious that there are other factors in play here. With those bullets, you could be seeing the effects of high ES and SD, or improper ignition from a light firing pin strike.


From the bench, is your vertical down to ~1" for 10 shots? No fair claiming that you pulled it, unless you saw the croshairs in the wrong place before it fired! If not ~ 1", you are likely fighting more than your technique.

I see double grouping, and I've had that happen for two reasons:

1) Scope was moving about (either mounts or the scope was the problem).
2) Recently, I've been fighting a 308 that shot well and started throwing high flyers all the sudden. It appears to be the barrel going away. In its case, groups were no better from the bench on a calm morning.