Ballistics question

[Rzrbck918]

Have a friend who has a 300 win mag and says he is 3.7" high at 100 yards instead of the roughly 2" high he desires to be. Aside from resighting in which he should do, he asked if because it is roughly 1.7" higher than it should be if that 1.7" in transferrable to the ballistic chart at say 300 or 500 yards. I hadn't ever thought of that question and I wasn't sure if it was that simple or if the math was based on minutes of angles and arcs that were not simply additive and he would see a greater change in POI at greater range.

 

[p_ham]

It's parabolic, the easiest way to figure it out besides shooting is just run it through a ballistics program. I like strelok Pro.

 

[buffybr]

It's hard to beat actual range verification...

 

[Rzrbck918]

It's hard to beat actual range verification...

Agreed.

 

[Dougfirtree]

Are you asking if the bullet will hit 1.7 inches higher than the ballistics chart says at 300 yards, because it's 1.7 inches higher at 100 yards? If so, the answer is no. As suggested above, a good ballistic calculator should give you a decent estimate of what it will actually do and then actual range time should tell you exactly what it will do.

 

[BucksnDucks]

Have a friend who has a 300 win mag and says he is 3.7" high at 100 yards instead of the roughly 2" high he desires to be. Aside from resighting in which he should do, he asked if because it is roughly 1.7" higher than it should be if that 1.7" in transferrable to the ballistic chart at say 300 or 500 yards. I hadn't ever thought of that question and I wasn't sure if it was that simple or if the math was based on minutes of angles and arcs that were not simply additive and he would see a greater change in POI at greater range.

If he's not going to the range the math is simple if he knows velocity and what projectile (BC and weight) he's shooting. There are other variables involved but the "simple" answer of zero and various yardage POI is easy to determine.

 

[Rzrbck918]

Are you asking if the bullet will hit 1.7 inches higher than the ballistics chart says at 300 yards, because it's 1.7 inches higher at 100 yards? If so, the answer is no. As suggested above, a good ballistic calculator should give you a decent estimate of what it will actually do and then actual range time should tell you exactly what it will do.

That is what I was asking, thanks!

 

[Wind Gypsy]

If he has to ask this he probably shouldn't be shooting beyond point blank range.

 

[winmag]

1.7” at 100 yards = 1.7 MOA.

So if he is 1.7” higher than he wants to be at 100 yards, that is also 1.7 MOA higher than he wants to be. This is transferable to all ranges on his drop chart; he will hit 1.7 MOA higher at all ranges.

If he has a quality scope that adjusts accurately, why not just adjust it down 1.7moa so he’s the 2” high at 100 yards that he wants?

As others mentioned, if he doesn’t know this then he shouldn’t be shooting beyond point blank range for his rifle. In other words, not shooting at distances that require adjustment or holdover.

 

[std7mag]

If he knows he's shooting 1.7" high, why not just adjust the scope for that 1.7" ??

 

[std7mag]

1.7” at 100 yards = 1.7 MOA.

So if he is 1.7” higher than he wants to be at 100 yards, that is also 1.7 MOA higher than he wants to be. This is transferable to all ranges on his drop chart; he will hit 1.7 MOA higher at all ranges.

If he has a quality scope that adjusts accurately, why not just adjust it down 1.7moa so he’s the 2” high at 100 yards that he wants?

As others mentioned, if he doesn’t know this then he shouldn’t be shooting beyond point blank range for his rifle. In other words, not shooting at distances that require adjustment or holdover.

1.7 inches at 100 yards, isn't 1.7 MOA.
Close, but not exact.

 

[winmag]

1.7 inches at 100 yards, isn't 1.7 MOA.
Close, but not exact.

Geez pedantic much?

1.7” / 1.047” = 1.62 moa

Happy now?

I’m sure my error of 0.08moa doesn’t matter when we’re talking about the difference between 3.7 inches and “roughly 2 inches” = 1.7 inches.

 

[rjthehunter]

If you dial, don't sight in 2" high at 100 yards. Sight in dead on at 100 yards. If he doesn't dial, then tell him to sight his scope in at 100 yards and move up 2moa.

How are you calculating velocity? Is he reading what the box says for velocity, or are you shooting over a chrono to verify? The question is confusing. But if he's 3.7 inches high at 100, and he wants to be 2. He should adjust down 1.62moa as stated above, and the rifle should be 2 inches high.

 

[Dakotakid]

Or just run the particulars through a ballistic calculator and print the chart. Verify that the calculations match actual.

 

[Don Fischer]

My chronograph gives me trajectory figures. I never trust them and go out and shoot against them at the real range. Darn thing has never been much wrong! But I still think it's a good idea to shoot against the data.

 

[Rzrbck918]

If you dial, don't sight in 2" high at 100 yards. Sight in dead on at 100 yards. If he doesn't dial, then tell him to sight his scope in at 100 yards and move up 2moa.

How are you calculating velocity? Is he reading what the box says for velocity, or are you shooting over a chrono to verify? The question is confusing. But if he's 3.7 inches high at 100, and he wants to be 2. He should adjust down 1.62moa as stated above, and the rifle should be 2 inches high.

Im sure he's reading the box. He's been a lifelong bowhunter and this is his first new rifle. Just getting going in the shooting side of things and has asked some questions I've simply never thought of.

 

[Don Fischer]

I've fooled with long range just a bit. Had my 6.5x06 sighted in at Max Point Blank Range and ran it through my Ballistics calculater and worked just fine. In the end I had my 6.5x06 dialed in for MPBR but if I wanted to could dial in longer ranges. Shooting those longer ranges showed it works!

 

[Kallcarrty]

What an interesting topic! When it comes to ballistics, it's like trying to hit a bullseye from a mile away in a windy field—it takes a bit of skill and some know-how. Speaking of which, using Kestrel Ballistics can make your life a lot easier when you're out in the field. This gadget takes the guesswork out of the equation by providing accurate wind and environmental data right at your fingertips.

As for your question, bullet drop is definitely something to keep your eye on, especially when you're stretching your range. A good scope and reliable ballistic calculator can help you dial in the right adjustments. Beyond that, consistent practice and knowing your rifle inside and out can really make a difference.

 

[kiwi hunter]

Seven clicks down

 

[grizzly63]

3.7" high at 100 will be low at 300 but probably still in the kill zone. IMO Seems like 5" high at 100 is dead on at 300.