QL and why or GRT

[ARlife4me]

I have both, but not as familiar with GRT use. These questions apply to all who have done this successfully or the knowledge to do how.
1. In a BA and with loads you have done with or without either program and using a chrono to confirm velocity.................have you been able to change inputs to match your outcome? And what was the biggest change needed or just a combo of some to all?
2. For those who have AR's and have seen the pressure at where the gas port would be noticed any difference in operation of the recoil system (good, bad or indifferent). What once was overgassed or undergassed that changed to the other. 1 could only see what the pressure would be at, but due to port size it didn't seem to matter on the outcome?

 

[Seabeeken]

I use GRT more than QL. GRT uses a 2 step powder model which makes it better than QL. GRT has more useful features than QL IMO.
1) Adjusting Ba in GRT is easy. Download your chrono data into GRT measurements tab and run the OBT. GRT will adjust the Ba to match you chrono data. You can also enter the speed into OBT manually if you prefer and then save as a OBT load for that rifle.
2) There are settings in GRT to adjust for gas port location and size, although I have not used them.
Grt has in the past been kept more up to date than QL although the powder database is smaller. Since Gordon's passing a year ago, there havent been much in the way of updates but there is a continuation team working on GRT now but it is slow going. You can go onto the GRT discord and share powder and bullet models with others. I've worked on the powder development team myself although not recently because of a lengthy move but will be back up and going soon. I should add, there is a wealth of knowledge in that discord and Charlie is the best there is for advice on GRT

 

[Highbrass]

I have both QL and GRT
I have just recently been exploring some of the features of GRT
Just worked up and shot my first OBT load.
The FPS calculated was exact with my Magnetospeed results.
I have to say I am impressed!

 

[asd9055]

I use GRT more than QL. GRT uses a 2 step powder model which makes it better than QL. GRT has more useful features than QL IMO.
1) Adjusting Ba in GRT is easy. Download your chrono data into GRT measurements tab and run the OBT. GRT will adjust the Ba to match you chrono data. You can also enter the speed into OBT manually if you prefer and then save as a OBT load for that rifle.
2) There are settings in GRT to adjust for gas port location and size, although I have not used them.
Grt has in the past been kept more up to date than QL although the powder database is smaller. Since Gordon's passing a year ago, there havent been much in the way of updates but there is a continuation team working on GRT now but it is slow going. You can go onto the GRT discord and share powder and bullet models with others. I've worked on the powder development team myself although not recently because of a lengthy move but will be back up and going soon. I should add, there is a wealth of knowledge in that discord and Charlie is the best there is for advice on GRT

No intention to sidetrack, but for bullet and powder data missing in GRT, could I use the data from QL, until GRT comes up with an update?

 

[Highbrass]

Just an observation
GRT seems a bit more information intensive. The more accurate data you feed it the more accurate the results it gives.
I'm still on a learning curve with the GRT, but I hope the people that have taken on its care will keep it updated.
Part of what was supposed to drive GRT was real world data from the users being added. I think that part of it is in limbo for now?
If you have QL it is no slouch but if you intend to use data from it to work in OBT I would think you should be ok to start out.
Part of the beauty of OBT is it is your input of your real world data that makes it work...

 

[ARlife4me]

No intention to sidetrack, but for bullet and powder data missing in GRT, could I use the data from QL, until GRT comes up with an update?

I have no idea. I've only tried to use it once.

 

[ARlife4me]

GRT is an external ballistics unlike QL's internal.

 

[asd9055]

GRT is an external ballistics unlike QL's internal.

I would disagree with that!

 

[ARlife4me]

I would disagree with that!

I didn't say only! That is only what I've read, but if you have any info otherwise then help me out?

 

[asd9055]

I didn't say only! That is only what I've read, but if you have any info otherwise then help me out?

I'll let @Seabeeken explain. He has more experience. I am an amteur user of both. I have been using QL for a long time and just strated using GRT about two years ago, but with components being where they are, I have not done anyithing this past year. Getting ready to start back up on a couple of calibers/rifles.

 

[TRG65]

like others I've used ql for years and loved it. Once I got a ql calibrated to a load I could extrapolate a bit. But a new combination would be an entirely new calibration.

From the first use grt was closer to actual and for several loads didn't require calibration. I've gone to just using grt.

 

[JustMe2]

I have both QL and GRT
I have just recently been exploring some of the features of GRT
Just worked up and shot my first OBT load.
The FPS calculated was exact with my Magnetospeed results.
I have to say I am impressed!
View attachment 427925View attachment 427926

Interesting that GRT would confuse the word "caliber" with "cartridge". The caliber is .243 and the cartridge is 6mm CM.

 

[Benchrest Braxton]

Interesting that GRT would confuse the word "caliber" with "cartridge". The caliber is .243 and the cartridge is 6mm CM.

You have to remember his native language isn't english. I am all for being technical too, but this dude was probably smarter than every single person on this forum so you kinda have to pick your battles haha

 

[Dancin' Crosshairs]

So...for those who say a precise prediction can be had using either Quickload or GRT, maybe you can explain this to me:

I have used both extensively.

Ba can be adjusted in either program to precisely match Labradar results. Wonderful.

The problem is that the Ba value used may seem to work well for one cartridge, but when the powder and the Ba value is used for a completely different cartridge the computed results are nowhere near real world results. The truth is, the default weighting factor (Siebert factor in GRT) value in these programs is not precise at all, they're just ballpark figures. The same can be said for Start Pressure values. These inputs all interact with the solution, and the values have effects on computed solutions every bit as significant as Ba.

I have not been able to begin imagining a method for determining precise inputs for these three parameters so that the Ba for a given lot of powder is known to be precisely correct.

If someone KNOWS, I'm all ears (or eyes). "Good enough" guesses are of NO use.