IMR 3031 Compressed Loads?

[Brian Pfleuger]

Anyone using IMR 3031 with compressed charges? I'm wondering how it behaves itself. Particularly interested in 7mm-08 info.

 

[Loader9]

I use it as a compressed charge in 223 ammo for a while. It didn't give me any issues. While I'm aware that there are much better powders available for the cartridge, I was sitting on a rather large pile of 3031 and it needed to be loaded in something. I tried 3031 in a 7-08 using a 115 gr HP, Speer as I recall, and it did okay but it wasn't a compressed load. Now that I think about it, just what are you loading in a 7-08 case that would be a compressed charge of IMR3031?

 

[Brian Pfleuger]

Now that I think about it, just what are you loading in a 7-08 case that would be a compressed charge of IMR3031?

QuickLoad suggests that the max load for the Barnes 110gr TTSX will be slightly compressed (in my particular gun). Something like 102.4%, 44.0gr. I don't intend to use max load unless it proves to be most accurate but I do intend to work up to it and find out.

 

[Loader9]

Sounds like Quickloads is quite ambitious with that data. Hodgdon shows a max load of 41.8gr with a Speer 115 HP. I would think the TTSX would have as long of a bearing surface or longer despite being 5 grs lighter. Good news though, you have a clue what yer doing so I won't be looking for yer name in the obituary column. Hope it works for ya.

 

[Brian Pfleuger]

I would think the TTSX would have as long of a bearing surface or longer despite being 5 grs lighter. Good news though, you have a clue what yer doing so I won't be looking for yer name in the obituary column. Hope it works for ya.

Well, there's a couple of things... one is that my case capacity is 1.2gr greater than SAAMI standard and the other is the design of the bullet. The bullet is longer, yes, but there are rings cut into the bearing surface that are supposed to bring pressures back down to near "normal"...

See? Ain't they pretty?

You may be right though, some of the variables are not yet fully defined. For instance, I still have to see what OAL gets me .050 off the lands before I can get a solid number for usable capacity.

QuickLoad has been very, very accurate with the 7mm so far though. Obviously, the total pressure is a bit of an assumption but when all of the known variables match the gun and bullet and the velocity matches the prediction then it's pretty safe, it would seem, to believe that the pressure is also a match.

Regardless, start low and work up, right!