Hello all , this may be a stupid question but here it goes . I just bought a rpr and want to load 140+ bullets . I get very good results with varget in my .308 with 178 amax' s so why is it not a good powder for lighter 140 gr bullets? Guess I don't understand why it's to fast . Thank you and thanks for bearing with probably another rehashed question . The rpr is a 6.5
6.5 creedmoor and varget
- Thread starter ny rifleman
- Start date
According to Hodgdon website, you can use Varget but you're going to get crap velocity out of a 24" barrel (less than 2,600).
For 140 gr in 6.5 Creedmoor (specifically in Ruger Precision Rifles), almost everyone is using H4350, IMR4451, or RL17 with great results.
For 140 gr in 6.5 Creedmoor (specifically in Ruger Precision Rifles), almost everyone is using H4350, IMR4451, or RL17 with great results.
Thanks , that's what I was getting at . I am getting more velocity in my . 308 with a heavier bullet ? Doesn't seem right
Think of like weight divisions in boxing. 140gr in the creed is like a heavyweight whereas 178gr in a .308 is more like a light or middleweight (compared to say a 230gr).
Also think about case size. 308 holds more powder than a 6.5 Creedmoor.
Starting load of Varget for 140 gr in 6.5 Creedmoor is 32.0 gr. Max = 35.8
Starting load of Varget for 175 gr in 308 is 42.0. Max = 45.0
I'm using Varget in my 6.5 Creedmoor AR-10 but I'm using it with the 123gr AMAX and I'm getting good results. I wouldn't use it with the heavier bullets but it does work well with the lighter bullets.
It's because of the smaller caliber diameter. You're trying to squeeze that much pressure through a 6.5mm hole vs a 30 caliber hole. The burning gasses and bullet can't get down the barrel as fast with the smaller hole, so the pressure builds too quickly and reaches max pressure sooner than ideal.
Using a slower burning powder like H4350 allows the bullet time to move down the barrel as pressure builds, creating more space behind the bullet before it hits the maximum pressure peak. The larger the total volume behind the bullet when it reaches max pressure, the faster the velocity you're going to get.
