The UK's Finest Independent Forum for Shooters and Gun Owners. Est 2010.

I have been given a Hodgdon reloading manual, dated 1996.
The book contains masses of data for a range of Hodgdon powders across a wide range of calibers and bullet weights.
My question is: will I gain anything by buying the latest version of the book;

Yes. The constituent ingredients change over time due to suppliers, manufacturing techniques and the like. Ensuring you have the most up to date data available will allow you to have the most efficient and safe loads that you can.

Hodgdon no longer produces a traditional reloading manual. There are two current sources of data:

The 'Annual Manual', a magazine format publication with up to 10 feature articles mostly from well known US gun writers followed by the loads data pages. As the name suggests, it's updated with new powders and cartridges and republished annually. It's a paid-for item, last year's £7 odd if IIRC. The 2017 edition hasn't got here yet.

Hodgdon's online menu driven Reloading Data Center. It has all the data of the above on a request basis, and is updated as and when for additions. It's free.

http://www.hodgdonreloading.com

The only paper manual i have is my first one.. the Speer Reloading Manual Number 11... published in 1987 when i first started reloading for my pistols.

... but I nowadays have bookmarked links to all the powder makers sites and their load data.