Gordan's Reloading Tool.

[ShadeTree]

I'm sure most of you are aware of it. A free reloading program similar I imagine to the quick load program. I've never used anything like that but I downloaded it and it was a windy colder day here today so a good day to mess around with it. It takes a little learning about it, and you have to enter all the data, or just trust what comes up for a particular bullet and the case capacity, but I found that is sometimes off.

Checked it with some known loads I have and have chrono graphed. I was impressed with how close it worked out.

My 200 grain CL load in my 35 Remington I chrono'd at 2325 with a 22" barrel. This program once all the data was entered predicted 2344.
Same rifle with the 180 Speer FP I chrono'd at 2350. This program predicted 2385. Predicted pressure on both was well under what I figured it was producing.

A M71, 348 Winchester load with the Hornady 200 FP & IMR 4350 was showing both over pressure, and way more velocity than what my chrono showed. I weighed the water capacity on one of my fired cases and changed that measurement accordingly, and the pressure came down to just under max working pressure, and the velocity was within 40 FPS of what I had chrono'd. Perhaps I should come down 1/2 a grain on that load.

I messed around on some other loads. Handy tool that I will be making use of in the future.

 

[Guy Miner]

It's a good tool, and I've used it, but... Perhaps an uncertain future since Gordon died?

Guy

 

[flyingagg]

Really good tool, and if you have like five velocity measurements for the same load, I can make adjustments and predict your OBT load.
Like Guy said, future is uncertain, but there is a group working on it. I still use both QL and GRT

 

[ShadeTree]

It's a good tool, and I've used it, but... Perhaps an uncertain future since Gordon died?

Guy

Really good tool, and if you have like five velocity measurements for the same load, I can make adjustments and predict your OBT load.
Like Guy said, future is uncertain, but there is a group working on it. I still use both QL and GRT

Huh. You 2 seem familiar with it. I haven't read around much on it other than learning to use it. So it might not stay around?

 

[flyingagg]

The developer passed away exactly a year ago. There is a group working on continuing the development. There is a good support group on discord. Time will tell

 

[ShadeTree]

The developer passed away exactly a year ago. There is a group working on continuing the development. There is a good support group on discord. Time will tell

So does it work off of data users provide? Or is it a program that just figures it out based on inputs? Most things were real close......case capacity on the 35 Remington was so close to what I measured, I didn't bother changing it. The bullet length of the Speer FP was off .050 from mine so I changed that.

The case capacity listed for the 348 Winchester was 76 grains if I remember correctly. My measured capacity was 81.9 grains, but that could be differences in chambers.

 

[flyingagg]

So does it work off of data users provide? Or is it a program that just figures it out based on inputs? Most things were real close......case capacity on the 35 Remington was so close to what I measured, I didn't bother changing it. The bullet length of the Speer FP was off .050 from mine so I changed that.

The case capacity listed for the 348 Winchester was 76 grains if I remember correctly. My measured capacity was 81.9 grains, but that could be differences in chambers.

This is my understanding. Anyone, please correct if I am wrong.
Caliber data comes from SAAMI or European equivalent. (They prefer using CIP type, but will use SAAMI when not available)
Same with QL, always adjust to your measured data.
Powder data is developed differently and addjusted with data provided by users. (you can not use QL powder for GRT)
Bullet data comes from manufacturers when ever possible. It also has some interesting ways of adjusting initial pressure according to bullet design, materials and primer type (magnum vs non magnum)
I am a TOTAL amateur, but plaaning to use it on my next load developement.

 

[hunter24605]

So does it work off of data users provide? Or is it a program that just figures it out based on inputs? Most things were real close......case capacity on the 35 Remington was so close to what I measured, I didn't bother changing it. The bullet length of the Speer FP was off .050 from mine so I changed that.

The case capacity listed for the 348 Winchester was 76 grains if I remember correctly. My measured capacity was 81.9 grains, but that could be differences in chambers.

It uses defaults to generate a projection. You can/ should add your known values like case volume, etc. after you get some chronograph data you can enter that in the “measurements” tab and then generate a GRT file from that and it will create a new projection using your data. Usually 2 or 3 velocity measurements is all it needs to develop a ladder and calculate the OBT. It’s surprisingly accurate most often, and usually spot on if you give it a couple real world velocities to work from. I haven’t figured out how to do it, but you can upload your data to GRT to help them further calibrate the powders, etc for updates.

 

[flyingagg]

It uses defaults to generate a projection. You can/ should add your known values like case volume, etc. after you get some chronograph data you can enter that in the “measurements” tab and then generate a GRT file from that and it will create a new projection using your data. Usually 2 or 3 velocity measurements is all it needs to develop a ladder and calculate the OBT. It’s surprisingly accurate most often, and usually spot on if you give it a couple real world velocities to work from.

@hunter24605 is correct. I did one test, after the fact and I was very close to OBT. Have new suggestions to try.
Now I am going to get 5 shot velocity measurements on a load and see what my suggested load will be. Planning this for a couple or rifles.

 

[ShadeTree]

I'm having a brain block. What's OBT?

 

[flyingagg]

I'm having a brain block. What's OBT?

Obtimal barrel time (Chris Long). QL does that as well

 

[ShadeTree]

Obtimal barrel time (Chris Long). QL does that as well

Okay. And you pre adjust your load to the OBT prediction once you have some velocity readings, and that is supposed to have you close on a accuracy node? Is that how that works?

 

[flyingagg]

Okay. And you pre adjust your load to the OBT prediction once you have some velocity readings, and that is supposed to have you close on an accuracy node? Is that how that works?

QL gives you the time and if yiu believe in OBT yiu adjust your load until you reach a time closed the the one for your barrel length
GRT takes your measurements and calibrated the data and predicts different nodes, including half notes. You pick the node and it gives you the amount of powder that would take you there. That’s the theory

 

[hunter24605]

Obtimal barrel time (Chris Long). QL does that as well

I'm having a brain block. What's OBT?

I’ve heard if you pinch you nose and blow really hard it’ll clear a brain block … it’s optimal barrel time, so far it’s 2 for 2 for me as far as being at least producing a MOA load.

 

[ShadeTree]

I’ve heard if you pinch you nose and blow really hard it’ll clear a brain block … it’s optimal barrel time, so far it’s 2 for 2 for me as far as being at least producing a MOA load.

Haha. I remember seeing that optimal barrel time on there. Information overload I guess, the OBT abbreviation threw me off, couldn't connect the obvious dots. It makes for a handy tool for some things I can see that. I'll have to mess with it more this spring on some loads. Just have to be careful it doesn't send me down rabbit holes away from some things I already know.