Going back over some notes from 2019, I find these results from H335 in my Ruger No.1 in .458:
450gr "X", 83 grs H335 = 2385 fps at MV
450gr TSX, 83 grs H335 = 2327 fps at MV
450gr Swift AF, 84 grs H335 = 2414 fps at MV
Going back before I had my CZ550 in .458: 75 grs H335 in my Ruger No.1 .45-70 LT under the 500gr Hornady = 2210 fps cprrected to MV; and 2317 fps for 76 grs H335 for the 450gr Swift AF corrected to MV. It had a 22" barrel. All signs indicated LESS psi than a load tested by Accurate for my previous No.1 (unmodified) in .45-70 firing the 500gr Hor at 2015 fps from the 22". Bill Falen Jr. pronounced that load safe that tested 2096 fps in their 24". The powder was AA2015.
I started using H335 in the No.1 with the long throat because I could use more of it than H4895 that was too bulky.
Some nostalgia, but was the basis for my use of H335 in the CZ 550 in .458 and later in the Ruger No.1 in .458. I learned a lot from that trail of experiences. One thing I learned was that safe pressure can be estimated from a number of sources - not from books when there is NO data (and there was none for my Ruger No.1 in .45-70 (modified). The second is that some others will follow pioneer work and build from it. It wasn't long thereafter that several sources began publishing results for H335 in .458s that far surpassed old data - Hornady the first who declared it best in the .458 Win and Lott. And that was well after 2230 had appeared on the scene. Now both are made in the same plant in St Marks, Flordia.
The point: Let's not forget that H335 is STILL one of the best in the great .458 WM using 450s and 500s.
