Re: H4350 Vs. IMR4350
Physically, the various 4350's appear to be smaller in kernel diameter than the 4831 varieties. The IMR versions that I have are also longer kernels, however both the Hodgdon's that I have are Short Cut (SC).
According to Lapua's Burn Chart H4350 is faster than IMR 4350 and IMR4831 is the same burn rate as H4831SC and H4831.
According to HOdgdon's Burn Chart, IMR 4350 is faster (#91), H4350 is #92 and AA4350 is #93. I would assume they're close.
IMR4831 is faster (#98) than H4831 and the short cut vers (#101).
According to Reloaders Nest, AA4350 is #212, IMR4350 #213 and H4350 #217. IMR 4831 is #225 and H4831 is #232.
This data can be confusing sometimes. The various brands (IMR,H,AA) are really close, but not interchangeable. 4831 is definately slower than 4350. JohnnyK.