G7 to G1 conversion

[Reelamin]

I thank you. I didn't know kestrel had any hammer bullets in its library. Busy day but when I get a chance I'll try to build it in mine and see. It's 5700 with the link ? I'm so fricking lazy/stupid when it comes to these apps and gadgets. They sure save a huge amount of time though. Thx again everyone

I will go to battle with you any day over all the Apps, Gadgets, and electronic clutter. We may be paying the price now.....lets see how everyone is paying the price just before we go to the best hunting grounds in the Universe. LOL.....just give me back my Oehler Program I put in my computer with a floppy disk and my yellow note pad I used to pace off or use cross fences for distances. You will get it dialed easier than you expect and your buddy will appreciate the help.....with a nice.....elk prime rib dinner!!!

 

[ShtrRdy]

JBM - Calculations - Drag Function Conversion

www.jbmballistics.com

Now this is potentially useful.

 

[Zen Archery]

Mathematical calculations get you close. Real world will factors will get you real world results. Even on the deep space James Webb Satellite/ Telescope. There were 30+ fail safe adjustments for every 1 calculated prediction. Those folks are literally aerospace engineers and mathematicians.

 

[BrentM]

I am not understanding why this is important. Is it because the turret maker is demanding a G1 number to cut the turret and do not give an option for G7? Generally turret makers just care about the drop data. You give them your dope and they cut the turret to the distance and dial. Nothing else should matter.

 

[Taylorbok]

I've heard a few people say AB has their numbers off for the Hammer Bullets but I don't personally know. It's pretty easy to put the info into a ballistic calculator (make sure all info is accurate) use a known MV and a guess for BC. Now shoot out to 600 compare the actual dope to what the calculator spit out. Go into truing and true your BC to the correct drop, boom done.

IMO I would just use a dope card. its easy to have a couple for different weather conditions.

 

[skipglo]

Your friend has to pick one bullet and bullet weight and confirm it shoots before he does anything else. All I read was he WANTS TO TRY Hammer. Custom turrets are only good a single round....in that way very limiting!

 

[RWeeks7mm]

The Applied Ballistic phone app not only allows G1 & G7, you can purchase a custom BC curve for your rifle/bullet combo for a couple bucks. I purchased one myself but have not had time to test it out.

 

[Tree Farmer]

This is exactly what I did. And I'm about the dumbest man on the planet when it comes to ballistic calculators.

 

[Tree Farmer]

My response to Taylorbok.

 

[PApa Black]

Is there a simple way to convert g7 to g1? I'm helping a friend do load work up on a hammer bullet and he wants to have a turret made for his huskemah ( not sure I spelled that right) . It's only for distance out to 600 so I'm hoping the box g7 will be close and I'll double check drop but they want trued g1 bc for turret info

NO: each bullet has different geometry. Velocity and stability also play into the calc.

 

[fmuguira]

As skipglo says, need to test bullet for accuracy first; THEN a BC conversion that's reasonably "close" will provide adequate dial ups to 'actually shoot the distances to his 600 yard request'. From that work one can end up with actual drops and decide whether to use a door card or request scope manufacturer to do custom turret.

Not all that hard; just gonna take some time to confirm actual field results. ( that really needs to be done even when a manufacturer tells you they can build a turret without actual drops and off bullet BC, elevation, temp and velocity assumptions)

IMO
Good luck.

 

[fmuguira]

Drop card… dang technology!

 

[parshal]

I ran some .22 rimfire over my Oehler 89 this weekend and collected both G1 and G7 BC. The simple math equations given in the thread get you close but they're still >.014 off on G1. That's a substantial different for the little 40 grain bullets. I don't think any of this will matter at <600.

I see a 7mm 133 Hammer in the latest AB database.

 

[baggy270]

I was thinking that as well and then make the corrections based on drop? He's only shooting inside 600 with this rifle. It's a slow twist 7mm rm and he's going to try the 131 heavy hammer. He shoots one deer and one elk every year

Seems like a lot of effort for that but it's his money