Quickload help or alternative?

[Movistar]

Hey gents. I’m having a hard time with my rifle not showing any pressure signs when I feel like it should as I’m getting up there in my ladder tests. I can’t use quickload because I don’t have a windows computer and it doesn’t seem to be compatible with Apple products.

Is there an alternative to accurately calculating pressures? I’m using RL-16 and Hornady 147 ELDM and I don’t know if either of these relatively newer products is even in quickload.

Here’s my recipie so far:

Peterson SRP 6.5 creedmoor brass. They weigh avg of 169.1 grn and water capacity is avg 50.6 grn.

Hornady 147 ELDM
RL-16 doing a ladder test Jumping .3 grn at a time from 39.9grn to 42.1 grn. 42.1 was avg of 2559 FPS out of my proof carbon 16.5 inch barrel. Primers are CCI 400.

No ejector marks of any kind. All my primers look exactly the same. Any advice? 2559 avg wirh a high of 2572 seems really high for a 147 out of a 16.5 inch 6.5 creedmoor. The barrel has exactly 68 rounds. The 2572 was number 68.

 

[AIAW]

I personally would just find an accuracy node velocity that I was content with. It's possible that you will hit that pressure wall very suddenly. I've heard of guys using ~44g of RL16 in fast barrels.

I'll run the QL calculation for you shortly. Nothing beats a real world ladder test and firing though (as you have done). 1-8" twist I am going to assume.

P.S: You can use VMware Fusion to create a Windows VM on your Mac.

 

[Movistar]

I personally would just find an accuracy node velocity that I was content with. It's possible that you will hit that pressure wall very suddenly. I've heard of guys using ~44g of RL16 in fast barrels.

I'll run the QL calculation for you shortly. Nothing beats a real world ladder test and firing though (as you have done). 1-8" twist I am going to assume.

P.S: You can use VMware Fusion to create a Windows VM on your Mac.

Yes it’s a 1/8 twist. I appreciate any help I can get. I want to push it on the faster side but not any where near the limit. I was thinking with the Peterson brass supposedly having less water capacity it makes any one else’s data I find useless. So I was waiting for a heavier bolt or a mark on the brass or primer or something but got nothing. Who knows maybe I’m not even close. It was chambered by Dave Tooley. He does good work.

I didn’t know I could still use it on my MAC. I’d need a Cd drive and that software still but sounds like it might be worth the investment.

 

[AIAW]

Yes it’s a 1/8 twist. I appreciate any help I can get. I want to push it on the faster side but not any where near the limit. I was thinking with the Peterson brass supposedly having less water capacity it makes any one else’s data I find useless. So I was waiting for a heavier bolt or a mark on the brass or primer or something but got nothing. Who knows maybe I’m not even close. It was chambered by Dave Tooley. He does good work.

I didn’t know I could still use it on my MAC. I’d need a Cd drive and that software still but sounds like it might be worth the investment.

Yeah, it will only install off of a CD. The whole system is antiquated, but it works decently enough.

What is your OAL on those?

 

[Carolina Hill Billy]

I personally would just find an accuracy node velocity that I was content with. It's possible that you will hit that pressure wall very suddenly. I've heard of guys using ~44g of RL16 in fast barrels.

I'll run the QL calculation for you shortly. Nothing beats a real world ladder test and firing though (as you have done). 1-8" twist I am going to assume.

P.S: You can use VMware Fusion to create a Windows VM on your Mac.

I used Crossover on my Mac for a couple of years with Quickload. Simply copy disc image to a thumb drive on a windows machine and it will load from there. I used Dropbox to sync with my other computers but that’s another thing all together.

 

[Movistar]

Yeah, it will only install off of a CD. The whole system is antiquated, but it works decently enough.

What is your OAL on those?

Wow I’m clearly not smart enough with computers haha.

The OAL is 2.810

 

[AIAW]

-------------------------------------------------------------------------------
Case capacity and propellant properties may vary considerably from lot to lot!

**** Input data:                         Date: 10-Feb-2019     Time: 13:24:27
Cartridge................. = 6.5 Creedmoor Hornady
Projectile type........... = .264, 147, Hornady ELD-M 26333 with boattail

Max.avg.pressure(Piezo CIP)= 63091 psi   Shot start / init pressure = 3626 psi
Projectile weight      (gr)= 147         Groove caliber         (in)= 0.264
Length of cartridge    (in)= 2.810       Length of case         (in)= 1.920
Case capacity(Grains Water)= 50.60       Length of projectile   (in)= 1.420
Length of barrel       (in)= 16.500
**** Values calculated:
Seating depth          (in)= 0.530       Volume displaced   (gn H2O)= 7.13
Comb.chamber volume(gn H2O)= 43.47       Projectile travel      (in)= 15.110
**** Input data:
Propellant type........... = Alliant Reloder-16
Charge weight..........(gr)= 42.1        Load density......(g/cu.cm)= 0.967
Heat of Explosion  (cal/lb)= 411694      Ratio of spec. heats cp/cv = 1.244
Solid density    (gr/cu.in)= 406.4       Weighting factor...........= 0.5
Burning rate factor Ba(1/s)= 0.43        Pro-/degressivity factor a = 1.348
Burning limit ......... z1 = 0.6         Combust.Chamber Vb(ft³)= 9.966301E-5
Factor.................. b = 1.979       X-S.Area of Bore A(ft²)= 3.730893E-4
Bulk density     (gr/cu.in)= 226.6       Projectile mass mp (lb)= 2.099868E-2
Loading ratio           (%)= 107.9       Projectile travel x(ft)= 1.259173E+0

**** Results calculated:
Maximum pressure ........ = 62923 psi    Way of projectile at Pmax = 1.99 in
Muzzle velocity  ......Ve = 2561 fps     Muzzle pressure .......Pe = 15028 psi
Project. energy at muzzle = 2141 ft.lbs  Fraction of powder burnt  = 99.5  %
Projectile travel time from 10% Pmax to muzzle = 0.97 ms

Looks like you are right at "max pressure" at 62,923 psi. Not too bad overall. If it performs, run with it.

 

[Movistar]

@AIAW wow thank you so much. I can’t believe what I’m seeing. Okay I need this program regardless of the hoops I have to jump through. That’s incredible. Thank you so much! Guys like you make this site and the shooting community better.

 

[AIAW]

No problem, thanks!

 

[AIAW]

Oh, also give yourself about 5 percent on these factors. Powder can vary lot to lot about that much at the extremes.

 

[Hawk in WY]

Next step is to read Chris Long’s work on Optimal Barrel Time and see if your are on a node for a 16.5 inch barrel.

Note QUICKLoad is estimating exactly your actual velocity and that Pmax and Z1 are on top of each other. Both are good things.

And yes you need this software.

 

[AIAW]

Yes, can't go wrong really. It's almost a Windows 95 GUI, but there really isn't a comparable product that's worth $150.

OBT is a pretty good start once you have some data. I usually find along with a few others around that generally 2 things apply though.

A) Accuracy nodes tend to be on the low side of the OBT prediction sometimes.

B) There are far more accuracy nodes than OBT nodes.

There are just so many variables. Still no good replacement for a real-world OCW or Ladder test.

 

[Bradu]

Yes, can't go wrong really. It's almost a Windows 95 GUI, but there really isn't a comparable product that's worth $150.

OBT is a pretty good start once you have some data. I usually find along with a few others around that generally 2 things apply though.

A) Accuracy nodes tend to be on the low side of the OBT prediction sometimes.

B) There are far more accuracy nodes than OBT nodes.

There are just so many variables. Still no good replacement for a real-world OCW or Ladder test.

When you do the OBT, do you measure case capacity and mess with the powder burn rate to match your actual velocity? I have read about it before and never really got a clear answer on it.

 

[AIAW]

Yes sir that's the basic idea, but I never adjust more than 5 to 8 percent. If I need to adjust more than that for the burn rate (Ba), something is off.

Contrary to popular believe, it's somewhat difficult to use QuickLoad for an initial load (outside of checking gross overpressure boundaries). You can sort of get close, but you're really just guessing at the burn rate for that lot of powder at a particular temperature. If you have a powder that has known to be stable from lot to lot then you can use a different load that uses that powder and as close to the bullet weight as possible as a baseline. The built-in Ba values in QuickLOAD are very good averages.

After you have a baseline of data into QuickLoad (fired brass case capacity, chrono data) you can really start to tweak it. Ideally you look for Z1 and PMax to be as close together as possible. Doesn't absolutely guarantee an accurate load but the chances are very high that you will be on or very near a node. Z1 is the point where the powder has stopped it's "active" burn. Ideally this would be where the peak of your pressure is (PMax). If PMax is way earlier than Z1 then you have a powder that is way too fast for that bullet. If it's way after, a powder that is too slow. All of these variable factor in while still maintaining an OBT (velocity). Speeding up or slowing down the burn or charge will change harmonics and of course, projectile speed.

None of this is fool-proof and set in stone to work every single time. It does however give you more focused areas to perform OCW or ladder testing around. Attached is the OBT Calculator Tool (Windows only) and the PDF table for various barrel lengths.

 

[Jammer Six]

If you need the results of the software, buy it.

Show some pride. Stop begging.

 

[AIAW]

If you need the results of the software, buy it.

Show some pride. Stop begging.

Where in the fuck that did that come from? Dude asked a legitimate question and he got plenty of legitimate answers.

 

[Movistar]

Haha it’s all good. I appreciate the help. I didn’t know I could run it on a Mac with some additional software. But today I bought a $200 dollar windows laptop that will be just for this. Thanks for the help, advice and showing me the value of the software.

 

[Jammer Six]

Well done!

I withdraw all my comments!