Thread: Calling all ballistics experts

Hi Team so iv had a 7mm RM for a year or so & I haven't had much luck dialling it if I use the shooter app its telling me with a 200y zero , at 400y it is -16 low at 500y -31.9 low so that = 3.8moa & 6.1 to bring it up to zero ..yet iv just done a bit of a drop chart today & its pretty much half of what the app is telling me so the actual drop is 8 inches low at 400 , & at 500 its 15.5 " iv checked all the info that I have put into the app it all seems correct :
bullet diameter 0.284
weight 162 eld-x
vel 3130.00
bc 0.6300
zero at 200y

I use the same app for the 308 it works really well so its got me stumped ! not sure if it makes a diff but the barrel is 26" long...thoughts ?