ballistic programs

[dully1963]

hi
back on again are ballistic programs any good for 6mm BR
I've been given a copy of quickload to try and it Say's that all my loads are dangerous but my maximum load is only 30.3 grns of varget or due you think this is an old program
any thoughts
all the best
dully1963

 

[CatShooter]

Hi, back on again.

Are ballistic programs any good for 6mm BR
I've been given a copy of quickload to try and it Say's that all my loads are dangerous but my maximum load is only 30.3 grns of varget or due you think this is an old program any thoughts.
All the best dully1963

I have found my program (Load from a Disk) to be dead on accurate. Whatever a program says (or a loading manual, or people on the internet), start low and work up.

 

[brian427cobra]

Garbage in Garbage out
this is a free online ballistic calculator
http://www.jbmballistics.com/ballistics/calculators/calculators.shtml
I use JBM with Lindy Sisk intructions and made my own Density Altitude Cards
http://www.arcanamavens.com/LBSFiles/Shooting/Downloads/References/

If you have a Iphone check out Ballistic FTE and BulletFlight

Last Saturday I was shooting a 5inch plate at 1000 yards, my Kestrel 4000 said the DA was 3000 feet, and my DA cards for 3000 feet said 8.0 mils to hit my target, I dialed 8 mils and sent a round, I missed because I didn't hold enough for the wind, I did'nt miss again after that, I was shooting 139 Scenars at 2810 out of my 260Rem.

 

[hmcsr]

Just did a quick look at my 6br and with my component specs 30.3 of Varget does not indicate as a dangerous load. That said, if you'll list your specs I'll run the m on my copy and see what we get.
I'll need:

• case brand
  case water capacity
  case length
  bullet type (brand)
  bullet weight
  bullet moly or not
  cartridge OAL
  powders you use

Regards,

Bill 8)

 

[CatShooter]

Just did a quick look at my 6br and with my component specs 30.3 of Varget does not indicate as a dangerous load. That said, if you'll list your specs I'll run the m on my copy and see what we get.
I'll need:

• case brand
  case water capacity
  case length
  bullet type (brand)
  bullet weight
  bullet moly or not
  cartridge OAL
  powders you use

Regards,

Bill 8)

I use 6mmBR with Lapua cases.
65 V-max, no moly
Benchmark powder
BR-4 primer.
OAL is 2.340"
~36gr of water (to the mouth)
24" bbl
14" twist.

My program is +10 fps from the real velocity. I can live with that.

I would like them to update the software, or somehow allow users to add new bullets and powders.

 

[TheSnake]

I would like them to update the software, or somehow allow users to add new bullets and powders.

If you are asking about QuickLoad, they do provide updates that add additional powders and bullets. The updates are not free though. I called support with a question and also got an update CD that had new stuff. I also think it is possible to add them yourself although not an easy task.

 

[CatShooter]

I would like them to update the software, or somehow allow users to add new bullets and powders.

"If you are asking about QuickLoad... "

Nope - "Load from a disk" It's an OK program but support sucks, and he doesn't answer emails

 

[CatShooter]

I use 6mmBR with Lapua cases.
65 V-max, no moly
Benchmark powder
BR-4 primer.
OAL is 2.340"
~36gr of water (to the mouth)
24" bbl
14" twist.

Somethin's not copacetic with your OAL Paul. Brass is 1.550" or so. The 65 V-Max is 0.835-0.840" and the boat tail makes up about 0.070" of that. At 2.340" the shank/BT junction would be about 0.025" out of the case.

Yup... I spent yesterdfday working with another caliber, and the numbers got transposed.
The OAL of the 6mmBR is 2.120"

QuickLoad doesn't take primer brand or barrel twist into consideration, at least the way I use it. I can understand that primer variations would be difficult to address but would expect some consideration of barrel twist as a variable. The energy used to spin the bullet isn't available to push it faster so fast twist barrels yield lower velocities than slow twists. QuickLoad must consider this "wasted" energy but doesn't let you vary it.

Accurate case volume is really critical to getting good output. The program expects the weight of water to be measured at overflowing (a convex meniscus). The best results come from using a case that's been fired in your chamber a few times and not resized since it most accurately represents the combustion chamber volume.

I think that some of this can be too OCD - since the program (which ever one it is) can work with some knowns, but can not even approximate other unknowns, then there is a threshold of unknowns that make a "data ceiling", or "noise floor" (whichever way you like to think about lost information)...

... so getting more and more data, that is smaller than the noise floor is kind of a lost effort, since the results are an approximation at best.

 

[CatShooter]

I think that some of this can be too OCD - since the program (which ever one it is) can work with some knowns, but can not even approximate other unknowns, then there is a threshold of unknowns that make a "data ceiling", or "noise floor" (whichever way you like to think about lost information)...

Probably true with primers although German might argue with that. Maybe with twist. Not so much with case volume.

What I normally see (case volume of ~39 grains of H2O): 32.8 gn Benchmark = 3,430 fps and 58,194 PSI
With your estimated (case volume of ~36 grains of H2O): 31.0 gn Benchmark = 3,380 fps and 58,788 PSI

The 32.8 gn Benchmark load in a 36 grains of H2O case, assuming it had been fireformed, would get some awesome velocity at 3561 fps, but would be on the hot side at 70,671 PSI.

Well... this is an example of what is wrong with having a religious belief in these programs.

My software gives:

31.1 Benchmark - 3325 fps - 48,075 psia
and
32.9 Benchmark - 3518 fps - 53,400 psia.

I am actually shooting:

32.5 Benchmark - 3490 fps - ~50,000.

Now my pressure is hard to document, since I don't have a strain gauge and pigtails hanging off the chamber, but the primers are rounded on the outside edges, and there is a soft rounding at the firing pin dent, so it is easy to place the pressure in the 50,000-ish psia range.

Now, this is not one of those "My ... is better than your... " It is just one of the many examples where we trust things that are not worthy of our trust. (Don't get me started on chronographs )

 

[CatShooter]

Well... this is an example of what is wrong with having a religious belief in these programs.

"... (if it's there it must be OK, right?)... "

Ain't that the "trut", which rhymes with "Ute" (if you remember "My cousin Vinny").

"... Access to a 500 yard range helps a lot.

A WHOLE LOT!!

 

[UltraBR30]

I have seen HUGE differences from QL to real world results. Primarily from .243 with light bullets. The velocity predictions from QL are not even close to actual. Then when you adjust the QL powder properties to get the velocity close, the pressure is not even near ball park.
I often wonder wonder how Hodgdon generates their data? And can't help but feel they generate it by such a program as well since I find it to be very inaccurate as well.
Nosler's reloading manuals are the closest for me to real world.