So quick question for those who have the experience I don’t. Trying to get ready for an elk hunt next season, and need to practice shooting longer range out to 500+. I sighted my 300wsm at 200 and made a quick dope chart using an online hornady calculator for the eld-x 200 gr. I do not have a chrono to know exactly how fast this bullet is going but speed was based on a 24” barrel which is what I have on my rifle.

But, how close would a factory bullet ballistic/dope chart be to actual?
Assuming I do my part, will the dope chart get me reasonably close, at least enough to make minor adjustments as needed or have you found the ballistic calculators to be way off

Good data in begets good data out. You've got good data in EXCEPT for your muzzle velocity. I've seen published velocity be true, and more often I have seen it be inflated. You have to go shoot it to find out. And if you're missing low, you need to lower the MV you have plugged in to the calculator until it matches. The good news is, you're MV can have a pretty significant error and you're still hitting center out to 500 yards. Right at 500+ is where you really get to true your calculator, backing in to the correct MV. So, on my range, the data I obtain at 600, 700, and 800 is the most valuable to back in to true MV.

Do you have access to a 100-300 yard range? If so, then you can sight in at 100, then shoot at 200 and 300 and based on the point of impact change, calculate the approximate speed of the round.

Either that or find someone who has a chronograph and get the actual speed of the round.

Just did a quick check and if you are off by 100 feet per second (which is entirely possible with factory ammo) and are using a 200 yard zero, you will be off by about 6 inches at 500 yards. Combined with a field hold that could put you out of the vitals, even on an elk.

I do plan to practice on my place where I should be able to get out to 400+, certainly 300 very easily.

I guess I always planned to verify, and I guess my thoughts of being on paper at 400 vs being off paper are not realistic, if I am on at 200 then I should be easily on at 400, even if low right?

You didn’t specify but I assume you’re using factory ammo. If that is the case make sure that all the ammo you intend to use sighting in and hunting is of the same lot #. I’ve saw very accurate factory amp have a point of impact shift of 3” at 200 yards when changing lot #s. As Mentioned above, make corrections until you’re hitting where you are aiming then adjust muzzle velocity in the calculator until it is correct. Using this velocity will give you fairly accurate corrections at any range.

Yes, you can "back in" to your velocity by starting with an estimated MV, then go to the field to confirm. Your data should be close enough to get you on paper or within the target area to make any corrections. When backing in to your MV, everything stems from a perfect zero, whether that's at 100 or 200 yards. Make sure that is solid first. Then go shoot it and figure it out. It also helps to know how well your rifle shoots that ammo to know how consistent you can be at distance. Groups always open up further out, generally.

I would print a drop chart that had drop data within 50 and 100 fps of the estimated MV. This will give you info for a little slower and faster for drop info.

That makes sense to have a dope for slower speeds. For hornady precision hunter eld-x ammo you think just getting a dope chart for 2820 (listed MV) and then 2770 and 2720 would be enough to be really close?

Honestly, I couldn't tell you 100% until you chrono it. Most of the time, they are within 150 fps of the listed MV. They list their 6.5 CM ammo at 2700 fps, but chrono'd at 2550. So, no telling. I would have data 100 fps either side of listed MV. If you are only going out to 400 or 500 yards, the difference in 50 fps isn't that much at that distance. But you will see more difference in drop to account for the further away you are from the listed MV. Anytime I am getting dialed in for the first time, I print a chart out with room to write in my actual drop data and compare it to my calculated data. But I shoot everything through a chrono to know what speeds I get during my initial testing so I have a known MV to work with. When backing into the MV, you have to be prepared for a change and know what that drop will be. At 300 yards, the difference is small. At 500, the difference will become more noticeable.

Appreciate the help guys!!

Like ChadTRG42 said, up close you won't see much of a difference with a rough estimate. However, the further out you go the more pronounced the delta. With commercial ammo, there will be some variance which you will need to take into consideration (see below).

One option is to look at hooking up with one of the more knowledgeable folks on here to see if you can trade a few shots through their chronograph for for a beverage or two (after range time).

I've seen slower than advertised velocities when using commercial ammo; rarely anything faster. Here is an example. 22" barrel on a 6.5 Creedmoor using Hornady Precision Hunter (advertised 2700 FPS with 24" barrel). Shot 1: 2706. Shot 2: 2696. Shot 3: 2642. Despite having 2" less barrel (compared to the advertised length) the first two shots were really close to the advertised velocity. The third shot was closer to expected (lose ~25 FPS per inch less). To me that is a pretty big spread considering it was from the same box.

Another option is to have someone develop handloads for your rifle; several very good sources on this site; if I lived in TX I'd be hitting them up. They'll typically find the exact combination that your rifle shoots the best. Your up front costs will be higher but when you see your groups shrink and the animals drop, it is money well spent. So far two of my rifles are using handloads with a third, and potentially fourth, going that route in the spring. I do wish that I would have gone this route sooner.

JG is right on the money. Published velocity is based on a particular ammo from a particular barrel length. You can't get reliable velocity data without chrongraphing your ammo from your barrel. You'll probably have scope error, so you'll have to shoot your rifle with your ammo on actual targets to get true Data Of Previous Engagement. That's DOPE.

For starters, you need to zero for 100 yards instead of 200. The reason for this: it's the longest distance you can set up as a constant without the risk of changing conditions causing a shift. In other words, if you zero for 200 yards at sea level then go up to 8,000ft elevation on an elk hunt, your zero may change. And if your zero changes, any elevation corrections from that are thrown off too.

Which leads to the next comment... changes in environmental conditions have to be accounted for in the calculator. You don't have to have a chrono, but an $80 Weatherflow meter that feeds into your ballistic app is almost a necessity given the goals you have listed. It's not going to be a huge factor while you're in Texas practicing, but you need to know how to integrate environmental measurements into your ballistic calculator before you travel to a different part of the country with a completely different Density Altitude range.

Last.... you definitely don't have to have a chrono to get good firing solutions, use the MV on the box and get some "try dope" for 300 yards. Go shoot it, then use your actual field dope to back into the correct MV for your calculator. Just remember your MV is going to speed up a little bit the more you shoot, hot chambers cook powder (especially if you chamber a round and take a long time to aim.) A chrono is nice to understand and teach yourself some of the finer details like that, also assessing performance of different ammo options with extreme spread and standard deviation. But you don't have to have one, just pick what ammo you want to shoot and stick with it. I'd suggest reading the following article for some more tips on getting practical dope without much dependence on calculators:

Weaponized Math

I'd stick to a 200 yard zero, but for the same reason. Too much happens further down range.

Yup....remember, a 500 yard shot up or down hill is not a 500 yard shot. Substantially less, usually.

This doesn't make any sense to me. A 100 yard zero is going to stay the same no matter what the conditions are. A 200 yard zero is not going to stay the same, and will change based on conditions. Now if you're hunting in Texas 100% of the time it probably isn't going to matter much either way. But if you are traveling and shooting longer distances, it does matter. And that's what we're talking about, because that's what the OP asked about. You're making corrections for distance based on that constant zero. Hard to have accurate firing solutions when your base constant isn't constant.

It depends on how up hill or down hill you are. You have to be shooting at a very steep angle for a substantially less distance correction.

And the newer angle compensating range finders are going to take care of that anyway right?

Not sure why this is an issue at all??