This podcast helped me figure out why my data was so messed up at a DMR match a few months ago. I was shooting 2-3 moa flatter than what my calculator said at distance, and just couldn’t figure it out. Just used the G7 BC in my ballistic app, and it shows exactly what I was observing at the match!

Don't forget that weight/mass of the projectile is an important component of BC. The two bullets shown have near-identical outside shape, but the lead-core bullet is approx 20% heavier. *THAT* is why the lead-core bullet has a higher BC than the all-copper bullet.

Ruben is a great podcaster, wish he could be on every episode.

This was a good one. As soon as it dropped I knew I had to watch it ASAP.

Always love these podcasts. Well done fellas

I was happy when I found out the difference!

This definitely helped clear up a lot for me. Biggest take away as a hunter - ground truth your equipment and verify everything based on bullet construction and its intensions - G7 sounds like its more dependent on standard shape when shooting WAY too far to ethically harvest animals, but is there in case you want to hit a target with the right calls after it goes transonic. Good stuff for the layman. % × ÷ 🧠

I use to watch these videos when they were truly 10 mins. one I looked at earlier was 1.5hrs.

Boys are putting out great content

Mark and those print outs lol

Manufactures also use G1 numbers on non G1 bullets because the numbers are higher and it looks better for sales also I think Barnes rates there BC numbers at 300 yards versus other companies rate them at 200 or 100 yd

BC is defined as a form factor multiplied by the sectional density. Two bullets can have the exact same shape (form factor), but different BC's if one is heavier Copper is less dense than lead, so a thin-walled cup and core bullet that is mostly lead will will weigh more and have a higher BC than an an all copper bullet of the exact same shape. Things get a little fuzzier with bullet designs that have a lot of copper and relatively smaller fraction of lead, like the Terminal Ascent bullets. They end up somewhere in between.

OOOOH, bringin in the heavy hitters

Multiple points here from different references. 1. In the Berger manual the way I read it was that the G1 is for more traditional bullets and the G7 is for (like y’all said) the higher performing bullets. But also that the G1 is based on the bullet at the muzzle. Many different MV will change the BC. If you run a G7 its at envy velocity. So someone please correct me if I understood that wrong. 2. A heavier bullet will have a higher BC because it can buck=k the air better but it will also be at a slower MV because of the weight. This is all dependent on if you run the load at a lower node vs a mid load vs a higher node. The Node selections should also be in the same realm. 3. Then we get to a lighter faster bullet or a heavier slower bullet with different BC… the more time it spends in the air (MV) the more time effects have vs the faster bullet spends less time so less time to be effected. I guess the real conversation and choice would be at what range to you expect to have a max range and then decide on the bullet. It gets deep. But great conversation. I love to get opinions on the science of it. I am the bullet geek that reads the front of he manuals and not just the data within.

Always use G7. Bryan Litz from Applied Ballistics would agree with me.

Is the GA category for airgun projectiles (diablo shaped pellets)?

Can't get away from discussing drag models even watching gun videos. But June is almost over.

Now I'm wondering if a faster than standard/recommended barrel twist or at least a gain twist that ends up there would help the older lever gun rounds. A .45-70 will be lethal as long as you connect with the target so if more aggressive twist would help stabilize it through the trans sonic barrier, why not?

My 308 - 168 match is close to G7, the 175 is close to G1 - very confusing. Good episode, thanks.

We need an episode where Ryan talks about the 16” 50 Caliber MK 7 rounds.

Ryan, you can have that Barnes performance with really high BC's. Badlands bullets.

You can do all the math in the world and maybe it's right but you need to verify your temperature sensitivity for your powder with a chronograph and verify your scope before you go with your calculated values. You should also verify your calculated values to determine error and apply to your table.

I wish you guys would've talked about how the posted BC on a box of factory ammo is only accurate at the posted velocity

Just how cold is it in that studio?

I don’t quite understand the reluctance to use a g7. It seems if I were looking at a bullet that seems it would benefit from a g7 I wouldn’t be asking why I can’t use a g1. Any reason Ryan tends toward a g1?

The basic equations assume that your bullet is shaped like the model. If you ever cover this again, just show pictures of the bullets used for G1and G7 models. If the bullet looks more like the G1, use that model, if it looks more like the G7, use that model.

👍🏼

So far G7 does not sync with good MOA wind constant for .223 77 grain and .308 175 grain match bullets. It is double the reality and thus only half of needed adjustment for wind and a miss for sure at long range from any wind.

Wow. I should have taken Physics

For some reason Reuben makes me think of a South Park character

Drag coefficient

25 Creedmoor

136gr .375 Raptor @ 3300fps is better then a 147gr 6.5 Creedmoor inside 400m. SR25. 16 inch. Comped.

Hornady 4DOF or nothing.

This isn't Hornady

First

Don’t use either. You should be using the custom curve for your projectile.

G1 for flat base projectiles, G7 for boattail projectiles, it couldn't be easier folks