Guys,

I went shooting this past Friday and after missing a couple of times at 900 I dropped down and shot at the 500 silhouette and found that I was shooting 3-4 inches high...ugh! So after realizing it I made some adjustments and took it out to 1k but I'm very frustrated! What can cause this? Can anyone provide a list of the variables and provide it in the order that I need to check them?

I have a Chrony Chronograph and am wondering if it's my reloads or if perhaps I'm just not getting a true reading on MV...

As for my loads...I've been pondering this and I've been consistent as far as I can think...

How much does the brass being the exact same length effect MV?

The toughest part of LR shooting to me are the variables!!! There seem to be more with LR shooting than there are in golf!

Did you check zero at 100 first, or cold bore 500 first?

Scope base, and rings tight?

Turrets tight to the scope?

What's the cartridge and how many rounds have been down the barrel?

Previous 500 yard DOPE, was it on virgin brass or brass FL sized with a .003" bump on the shoulder?

Was this brass virgin or FL sized with a .003" bump on the shoulder.

Are you Mils or MOA? You would be 3/4 MOA high, or .2 Mil high.

Friday was cold, and I would expect an impact low, not high. So that's why I ask all these questions. And you dang right there's lots of variables, but not inside 500. Heck even a .308 Win will have the same DOPE to 500 all year long in all DAs and temps. Outside 500 is where it gets dicey.

One thing I've gathered in trying to learn about shooting LR in the field--Powder can be extremely inconsistent in regards to lots/batches, and can give extreme variations in different temps--that can mean a lot if you load/test in the summer, and try to make the shot in fall/winter.

Alliant powders (usually the ones for overbore magnums) are the ones I've learned to stay away from--the Hodgdon extreme series seem to do well.

The one thing I do know is that the variables can/will drive you insane.

Good advice...the way I would rat thru details.

Ed

Everything fireman said, what powder ? Use the same primers? Neck tension change I have seen do that too

Exactly. We need a lot more info to answer your question.

What were the weather conditions on your previous range trip?

All your loading components from the same lot as last time? I ask because you had mentioned getting powder in big numbers. A lot difference can definitely cause this issue.

I had shot and hit the 500 yard targets but honestly it was getting dark and I was just running thru the yardages and I'm not sure if it was 800 or 900 that I missed first but anyway after missing a couple of times and not being able to see my misses I backed down to 500 in order to get my bearings so I could get back on it at 900 and then 1000 and fired two rounds at the 500 and saw the hits and they were about two inches apart...at least that's what it looked like thru the scope and they were both 3-4 inches high. I don't mind saying it's pretty tough to shoot without a spotter...at least for me.

I use H4350 and no it's not all the same lot because I haven't been able to find that much at any one time...I'm definitely trying too but...

Yes, same primers, neck tensions? How do I measure this?

Wow...and I thought I had most of the variables covered.

No...expensive learning curve! Agh! Lol

I've had a 120 fps increase in velocity with the same charge of H4350, just a different lot #, from my 260 Rem with 140 VLD's. So, yes, keeping the same lot of powder is important.

You did not answer all of the questions asked.

500 yd shot was not cold bore...I shot 5 rounds at 100 while I was using the Chrony on my AR to get my MV on it. And no I didn't shoot it thru the Chrony to check because someone else was there that ask me if I'd let him use it to Chrony his rounds. So as soon as he was done I packed up and headed to the 1200 yd range. It was shooting 1" high at 100.

Crap! Crap! Crap!

The rifle that impacted high at 500 was 1" high at 100?

Well there ya go. Your 100 yard zero was 1 MOA high on zero or .3 Mil high on zero. Same offset you had at 500.

If it's a 260 shooting 140 A-maxes it should be 2.6 Mil at 500 yards with a 2800 fps MV and zero correct at 100 yards.

Man, it sucks to get old! Another brain fart! Over thinking everything...ugh!

EVERYTHING stems from a proper zero! If you don't have a solid zero, you will be off or guessing on your elevations.

I had a guy about 2 weeks ago get upset that he was 13" low at 500 yards with some custom ammo I loaded. Like really upset. So I calmed him down and started from the beginning. He had a 200 yard zero. I asked him when was the last time he checked it, and he said right before he shot 500 yards. It was 1.5" low. So I ran the numbers. I came up with 9"-10" low, just from the 1.5" low off his zero. (The other 3", I think could be the different powder lot and cooler temps, but what's 3" at 500 yards. Account for it, and adjust your dope.) So, he understood a little more about how important a proper zero is, and was going to correct it.

If you change powder lots, it most likely will change up your speeds, which will effect your trajectory. This is why I buy 2- 8# kegs for my competition ammo, to make sure I have the same lot # throughout. At 41.5 grains of powder, that's 2698 rounds of ammo that I don't have to rework my load and get new speeds.

When you get out 500 and beyond, everything makes a difference, everything.

Mil vs tenth of mil is where the brain fart was...embarrassed to admit it...ugh!

I'm pretty sure a know this but...will change in powder lot effect POI and not change MV?

It could but unlikely...it typically changes MV and the result of that is POI.

One thing I learned a long time ago, there is no absolute in loading. You just have to try it and proof it to yourself. One thing I can tell you is swapping between lots will kill you.

So, how many 1lb'ers of different lots do you have? Here is the reason I ask....if it is a bunch (10+) you can make your own lot...get a big bucket and pour them all together and mix very thoroughly! VERY IMPORTANT, to rework up to your load after your mix.

Good luck. I haven't seen H4350 since Feb 2014...I'm surprised really. Varget has even been easier to get than H4350.

Guys,

As always...you guys are GREAT! Thank you for helping me! Went to the range yesterday and got things straightened out. I didn't have time to go to the long range and check it but hopefully I will Friday afternoon. I'll let you know how it performs!

Thank you!

Mel

NP peeks in and says "This thread shows why most folks have no business shooting at any animal past 500 yards."

You guys know your stuff. Impressive.

NP leaves....