Shooting @ 600 for the First Time?

[scsims]

I've been trying to begin shooting at longer ranges lately and finally hit the 600 yard mark.

I'm using a .308 with 168 SMKs at 2740 fps.

I'm using the Shooter program on my smart phone and the vertical MOA is pretty close, but I'm struggling with the wind. I've shot at 500 yards twice over the past two weeks and 565 once and at 608 yesterday.

The wind has been variable at 8-12 mph changing from 45-90 degrees for the wind angle.

I'll dail for the wind and let 3 fly, go check and 2 bullets will be together almost like there was no wind and a third will be where I dialed for wind.

This has been the other way as well. So I'd go back and think well the wind isn't that bad and I dail for less wind about 1.5 MOA and shoot 3 more and 2 will be far left from wind movement and a third hit as is there were no wind.

The last two groups at 600 were actually together. The first group I dialed for 2.5 MOA of wind and hit about 6 inches right as if there wasn't much wind but the 3 shot group was 3.75", the second group I dailed for less wind and it was almost centered but a little larger group at 5.5".

With all this said I mainly feel that I'm just new at this and have a problem judging the wind with each shot.

Would choosing a different bullet help? Maybe the 155 Palma MK, or the 175 SMK?

 

[Scot E]

Variable wind speeds are difficult but wind that are show significant change of direction can become nearly impossible at times. Figure out a directional and velocity wind scenario that occurs consistently and then wait for it to happen for each shot. You should see your groups shrink.

Having said that, have you ever shot that distance in a no wind situation so you know what your potential is? It may be that part of your issue is being caused by other things like form issues, etc.

Scot E.

 

[scsims]

No I haven't shot on a total windless day, it's tough to get a windless day this time of year. But when the wind seems like it's almost stopped is when I get them to group.

Should I try some of the other bullets that might buck the wind a little better?

 

[Scot E]

How are your 100 or 200 yard groups? If you are getting good groups then I don't think it is a bullet issue. Increasing to a higher BC bullet isn't going to tighten the flyers you are getting necessarily.

It could be that you have a reloading issue that is causing the flyers. Trying to chase an issue when there really are 2 or 3 that are ganging up to cause the problem can be really frustrating.

Scot E.

 

[scsims]

At 100 yards I usually able to keep them under an inch. Best group being .440"

At 200 I average 1.5" and best group about 1.125"

 

[bman73]

are you letting the barrel cool between shots or just blasting 3 out rapidly. Maybe try get closer to cold bore and see if that tightens things up a bit.

 

[HARPERC]

Variable wind speeds are difficult but wind that are show significant change of direction can become nearly impossible at times. Figure out a directional and velocity wind scenario that occurs consistently and then wait for it to happen for each shot. You should see your groups shrink.

How are you determining wind speed? Are wind indicators available downrange? One place I shoot can be dead calm at the firing point, but a styrafoam cup on a string at 200 will be stretched indicating a full value breeze one direction or other. Even the variables can be variable at 600 yards. My checklist would include making sure your putting good readings into your program. Scot E's advice to make sure you aren't experiencing more than one problem is sound.

 

[Greyfox]

At 600 yards a 2 1/2 mph wind error can cause as much as a 1 MOA deviation with your load. I would look closely at your vertical dispersion to get a rough idea of your non wind shooting variables. If your vertical group measurement are cocsistant with your 100-200 yard groups, it's a decent indication that you wind dope is of for the fliers. If you plan on progressing much further out than 600 yards, I would consider changing your bullet to the 175 SMK. The 168, due to the steep boat tail design, is believed to exhibit stability issues at the longer ranges.

 

[scsims]

Thanks for the replies..... I'm going to keep trying.

Today there was little wind almost directly out of the north at about 3-5 mph. I was shooting at an angle of 160 degrees. This time I shot three groups of 5 rounds and I would go check the target for each group.

This was at 600 yards again. Altough each group of 5 had 1 flyer 4 out of each group stayed within 1 MOA of each other with the smallest group at 3.25" The last 5 shot group where centered in the target for about a 5" group. The smallest was the 2nd group but was in the lower left corner of the target, I adjust a little too much from the first group which was high to the right. But got where I needed to be with the final group.

I'm pretty satisfied but I know I'll have the same issues each time I move the target out further.

 

[RMulhern]

If you're shooting the Sierra 168...change! That bullet has a 13 degree boat-tail and any bullet with that design has the same drag function as a flat-based bullet! It's dandy...for what it was designed for which was 300 meter International competition but a long range bullet...it ain't! Go either with the Sierra Palma 155 gr. or the 175 gr.!

 

[scsims]

If you're shooting the Sierra 168...change! That bullet has a 13 degree boat-tail and any bullet with that design has the same drag function as a flat-based bullet! It's dandy...for what it was designed for which was 300 meter International competition but a long range bullet...it ain't! Go either with the Sierra Palma 155 gr. or the 175 gr.!

So which would you recommend for 600 to 1000 yards? The 155 or 175?

 

[albertakid]

I shoot the 168 grain a-max and accuracy doesn't seem to be an issue to 1000??? It definatley isn't at 600 yards where I have shot a ton. I have thought about going to the 175, but this gun holds sub .5 moa groups with my current load...I have had all sorts of people tell me that the 168's won't carry to a grand, but I have seen diffrent results in the field ymmv.

Jordan

 

[scsims]

My rifle has a 1 in 12" twist, will it stabilize the 175 SMKs?

 

[RMulhern]

So which would you recommend for 600 to 1000 yards? The 155 or 175?

If running a 1-13 ROT I'd go with the 155! Anything faster I'd go with the 175!