Seabee
Old Timer
It’s working fine now. Using the obt feature it has put me on a node every time. Excellent program. Hope they get more powders in the database soon.
Is there a good place to get initial pressure information on primers for GRT? Yes I saw the wizard, but was looking to double check.
Been playing with GRT lately, thanks for this, it seems to be working very well for my 300wsm loading so far. Says I need to trim .1gr off my load to hit the OBT, I'll give it a try and see.
Now... what are you using to calculate exterior ballistics for long range dope? I have at least 3 different options, first one I tried at PNTC this weekend for the first time really did not impress me, my dialups were all short, but the other two, which I did not try yesterday, we giving me higher values, so I need to play around and see who it right.
I need a Kestrel, but BallisticAE is what was giving my low dialups. I compared it to Shooter and the Hornady 4DOF calculator and they both told me to dialup significantly more, so I'm not sure what's up with BallisticAE.I use the my Kestrel but also use the iPhone app Ballistics AE. Before I got the Kestrel Ballistics AE was getting me on target out proven out to 1200yds.
I need a Kestrel, but BallisticAE is what was giving my low dialups. I compared it to Shooter and the Hornady 4DOF calculator and they both told me to dialup significantly more, so I'm not sure what's up with BallisticAE.
I also just downloaded Applied Ballistics, since I'm using Berger bullets and I can get the doppler data that they use that way. It also agrees with Shooter and pretty close to the Hornady data, all way off from BallisticAE given the exact same data... strange, but I think I at least have some firing solutions that should be closer next time I get a chance to test something long range. We'll see... lol
I am completely new to reloading - just getting started. I found GRT via another forum, and I've learned more in the last hour of playing with it about reloading/load development than I have in the past two weeks of reading manuals and watching 'tube videos. Been putting in loads from a Nosler manual and seeing how they come out, then diddling the parameters to see the effects. What a great tool!!
One thing GRT is handy for is that it can tell you whether a load is likely to cycle a gun... just swap the chart from time to barrel length, and you'll see estimated pressure at each point in the gun. M16A1s cycled with about 12.5k at the port (optimally), if that gives you a sense for the kind of pressures you should be seeing. Also demonstrates why pistol and carbine gas tends to be so violent.
The answer is yes. Even with the current data in GRT, it's pretty easy to see why something like CFE BLK or 1680 will cycle an AR with pistol gas using 200gr subs whereas Lil Gun will not. Port pressure is a real thing.Thats a great idea. Is there any way to use this to tune subsonic rounds like 300B/O.
In GRT you basically pick three things and then modify the parameters as necessary within them. I usually use it in expert mode
A -
1) pick a cartridge (Upper left preppy box, with the search magnifying glass)
2) pick a bullet (upper center, with the search magnifying glass)
3) pick a powder (lower center, with the search magnifying glass)
B -
1) Within the cartridge pane, I usually adjust barrel length to start
2) I usually don't change anything in the bullet pane if I've picked the exact bullet I want
3) within the powder pane, I adjust:
1) the powder charge weight
2) the number of load ladder steps.
Then see result in the results pane...
When it comes to computer programs, I can't get the baby food into my mouth without someone doing the "airplane spoon".
I can do long division in my head and rebuild a carburetor without instructions. When it comes to basic computer stuff, I'm a complete idiot.
Don’t give up. You are only 50yrs old. Computers are going to be around for the rest of your life.
The screen has a lot of info but Once you get familiar with it, it will start to make sense. First dont use Advenced/Expert mode just starting out. Below is a screen shot using standard mode. Like Antartica said, there are really only three things you need to click starting out. I just numbered them below.
1) Cartridge - In the screen shot mine has 6.5 Creedmoor shown. Click that little box/button and then you’ll get a new menu box which will allow you to access the cartridge library. Just browse through and select the one you want.
2) Do the same for projectiles. There is a good chance you’ll find off the shelf brand name ones in the library. Some off brands may not be listed. You can create your own later once you get more comfortable.
3) Do the same for power. There are more gaps in the power library but they are adding to it all the time. Once you select the powder brand, you can adjust the charge weight just below that selection box. Simply click on the number and type in your charge.
4) Once you enter the charge weight the load data should automatically populate the fields. You want muzzle velocity and case pressure data. If you make adjustments to any of the parameters on the left, the load data will update automatically.
One day we may have to do a beer tasting/ GRT training session.