.223 ballistic mystery...

[bellavite1]

Have you tried putting in speeds far lower than what you expect to give you that rise? It doesn't make sense to me that the bullet would have to be going 5,000fps+, rather than much slower. I'm not great at this stuff, but I haven't seen anyone else suggest it so far.

Also, rage quitting your own thread out of frustration over some light miscommunication isn't going to get you anywhere.

True, but one person's reply was starting to border personal insult, and THAT is not helping anyone.
Again, my main concern is: is there any reason why my ballistic calculator App, which has been spot-on so far in many different loads all of the sudden does not match real world results?
What could I have actually messed up to cause that?
To answer your question, yes, I have tried entering lower speeds and they would actually reduce the climb.
I will change my zero to 200 and see what happens.

[Grant H.]

You haven't actually shown anything that "verifies" a discrepancy between the ballistics app and real world results.

As CWard has been saying, every picture of a group that you have posted has been 3-4MOA. A perceived 1" discrepancy in POI while shooting 3-4MOA groups doesn't mean anything.

A few more data points that might help in all of this:
- Barrel Twist Rate?
- Gas length of rifle?
- Is the 62gr Hornady that you were shooting factory ammo, or reloads?

[bellavite1]

Twist is 1:7
Carbine lenght gas system
62 gr is loaded over CCI primers with 25.4gr of CFE223

[Grant H.]

62gr is pretty light for a 1:7, which may be a good chunk of your 3-4MOA grouping.

The 69gr that you mentioned buying should help, but even up into the 7Xgr will stabilize better, and should help to tighten groups up.

FYI, this thread shows a guy having really poor luck with velocity and accuracy out of very similar load and rifle configuration. https://www.thehighroad.org/index.ph...d-dots.864212/

If it were me, I would ignore the ballistics "anomaly" until you get a load that the rifle likes, and then re-run your tests.

[bellavite1]

Thank you, good info.

[izzy]

I've got a bunch of heavier projectiles if want a few to test out shoot me a dm.


Eta: and I mean you can just have a few, not trying to sell them

[Duman]

Have you tried putting in speeds far lower than what you expect to give you that rise? It doesn't make sense to me that the bullet would have to be going 5,000fps+, rather than much slower. I'm not great at this stuff, but I haven't seen anyone else suggest it so far.

I thought I mentioned that....

[bellavite1]

I've got a bunch of heavier projectiles if want a few to test out shoot me a dm.


Eta: and I mean you can just have a few, not trying to sell them

Thank you so much for the offer.
I actually have 500 Sierra Matchking 69gr coming Monday, I'll see how they work first...

[izzy]

Thank you so much for the offer.
I actually have 500 Sierra Matchking 69gr coming Monday, I'll see how they work first...

Let me know. I have serra 77s and hornady 75s if you decide you want to experiment.

[Duman]

62gr is pretty light for a 1:7, which may be a good chunk of your 3-4MOA grouping.

How would a faster twist rate (1:7) vs., say, 1:12, affect the grouping?