Why does my M1 make two groups like this?

[MZ5]

The 3 shots on the paper, plus the 3 just off are all from the same string of fire. 100 yds, just testing a load. However, it does this with other ammo as well. In fact, in the last C&R match I shot, I had wider spreads, but the same general pattern. I didn't/haven't watched closely enough to see if it alternates according to which side of the clip the round feeds from, though it wouldn't surprise me if it was that. The question is: Why does it do this, and how do I get it to put them all into 1 group?



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[browningautorifle]

The reason you'll have a split group is because you've changed your position or an elbow shift. It has nothing to do with the ammo, clip feed or rifle. A vertical group is breathing, lateral spread is elbows moving. Two separate groups, if one of these is above the other is a different point of aim. That could easily mean the foresight tip not centralized in the aperture. I take it this was rested and on a bench?

The way to overcome this is careful practice...perhaps a coach while you shoot.

[MZ5]

This was laying across a bag (not a sandbag, my range bag) out in the desert. The C&R matches are slung up (of course). While I do not say that this is not an aiming or position issue, it's almost ludicrously repeatable/repeated. I wonder what I could be doing so very precisely and repeatably, but in two different ways...?

[browningautorifle]

I lay on firing points beside recruits for decades and watched this sort of this incessantly.

[cipherk98]

BAR may not be far off. For what it's worth I find targets where my POA is on a square or edge versus a circle are harder to center on at distance.

To be clear, when you shot the string of six did you shoot three, reload, shoot three? Shoot one at a time, checking your scope each time? Shoot six in a row without moving up off the gun? Did you have a spotter calling each shot? This can help narrow down what is happening.

[MZ5]

No, this was one en bloc clip. The first two I was aiming elsewhere, until I found about where POI was vs. POA (this was load development with Lapua's 185-grain D-46 over AA4350, whereas I normally use lighter bullets and AA4064 in this gun). Once I found it, I moved to a new POA and fired the remaining 6 rounds in the clip, and those 6 holes are what I got. I don't have a spotting scope so I can't say for sure with just my eyes that it was one-then-the-other alternation.

[browningautorifle]

BAR may not be far off

Gee, thanks.

You'd be surprised what an educated coach would see when watching you. There are so many variables here, without me actually being there how can we actually say? I didn't examine the rifle pre firing, I didn't watch you while reloading, I didn't test and adjust your firing position...I didn't watch you shoot the group. But I have a good idea...

[cipherk98]

No, this was one en bloc clip. The first two I was aiming elsewhere, until I found about where POI was vs. POA (this was load development with Lapua's 185-grain D-46 over AA4350, whereas I normally use lighter bullets and AA4064 in this gun). Once I found it, I moved to a new POA and fired the remaining 6 rounds in the clip, and those 6 holes are what I got. I don't have a spotting scope so I can't say for sure with just my eyes that it was one-then-the-other alternation.

Next time see if someone with a scope might be willing to spot for you or see if anyone you know can go with you. For me personally, going left to right or up to down on each shot is due to my POA wandering, typically if I shoot a string then reload and shoot another to find them going somewhere else it's because I moved when I settled back down.

Gee, thanks.

You'd be surprised what an educated coach would see when watching you. There are so many variables here, without me actually being there how can we actually say? I didn't examine the rifle pre firing, I didn't watch you while reloading, I didn't test and adjust your firing position...I didn't watch you shoot the group. But I have a good idea...

The shots you knew you missed the moment you pulled the trigger are easy. The subtle ones are a real pain. Like when you're mid string and drop 4 or 5 shots for no reason then magically pick it back up. What you're talking about bites me the most when shooting the sitting rapid stage... seems like I can never get into the same position I was in when I took my sighters. Coincidentally it's also why I changed how I now test handloads - used to shoot one at a time and check each time on the scope. Now I shoot one for POA/pressure signs, load 5/8/10/whatever and shoot without looking up again.

[browningautorifle]

What you're talking about bites me the most when shooting the sitting rapid stage

That's another thing many can't grasp, the four positions have four different MPI and you have to be aware.

[Ovidio]

I guess I have a lot to learn still...................