300 RUM and TTSX bullets

jmquarles · September 28, 2010, 02:20 PM

I am reloading 180gn Barnes TTSX bullets for my 300 RUM. The max load in the Barnes manual is 93gn of Rutumbo powder, while other manuals show max loads for other 180gn bullets is over 100gn of Rutumbo powder. Is this because the TTSX is slightly longer? It just seems like a big difference in powder charges for the same weight bullet.

Brian Pfleuger · September 28, 2010, 02:23 PM

It is partially because the bullet is longer, partially because the all-copper construction causes a higher starting pressure and partially because load manuals often have wildly different data for identical bullets, say nothing of different bullets.

Start with the lowest starting load you find and work up toward max, looking for pressure signs.

September 28, 2010, 02:20 PM	#1
jmquarles Junior Member Join Date: September 28, 2010 Posts: 1	300 RUM and TTSX bullets I am reloading 180gn Barnes TTSX bullets for my 300 RUM. The max load in the Barnes manual is 93gn of Rutumbo powder, while other manuals show max loads for other 180gn bullets is over 100gn of Rutumbo powder. Is this because the TTSX is slightly longer? It just seems like a big difference in powder charges for the same weight bullet.

September 28, 2010, 02:23 PM	#2
Brian Pfleuger Moderator Emeritus Join Date: June 25, 2008 Location: Austin, CO Posts: 19,694	It is partially because the bullet is longer, partially because the all-copper construction causes a higher starting pressure and partially because load manuals often have wildly different data for identical bullets, say nothing of different bullets. Start with the lowest starting load you find and work up toward max, looking for pressure signs. __________________ https://ecommercearms.com I am the owner/operator! Ask me for custom prices! No sales tax outside CO!