I was reading the Long Range Hunting board and came across an alarming thread. A guy basically welded his RUM 300 shut. Broke the bolt handle off at the range trying to open it. Took it to his gunsmith and for three hours they tried everything they could think of, but nothing worked. He ended up sectioning the rifle with a saw and finally the bolt body was able to turn. Now the ODD part. The day before he had been shooting Nosler and Berger bullets using Retumbo. The temp was 3 degrees Fahrenheit. He finished the day with no issues. He came back the next day and it was -10 Fahrenheit or a Delta of 13 degrees COLDER. He fired some and Berger 190s loaded over Retumbo.
In his words:
"Well. I destroyed my 300 RUM today.
Yesterday I was testing some load development on my 300 RUM with Berger 230 with Retumbo.
Everything went well and found a load that appeared to group well. 86.8 gr. COL of 3.600" Federal 215 primers on Hornady Brass.
The temps were 3 degrees and a slight breeze bringing the windchill temps down to -15.
I went home and loaded a few more rounds at that charge and try a couple other loads.
Today it was -10 with a 20mph wind. For some reason no one else was at the range. I fired 20 rounds of 190gr Nosler Accubonds to make sure that everything was working well and to warm myself up a bit. I am getting about 3100 fps out of the 190s with Retumbo at 91.5gr
20 rounds fired and not a single issue. I was firing a 2 rounds then I would let it sit for few minutes and fire other rifles.
About an hour into it I then switched over to the 230 grain rounds. I fired the first round. 3129fps and I couldn't lift the bolt. Something was seriously wrong. I broke off the bolt handle trying to open it at the range hitting it with my hand trying to open the action.
I took the rifle to my local smith and I attempted to get the bolt out. After three hours f trying everything under the sun, No luck."
Now I'm scared of Retumbo, although I have shot several hundred rounds with it just trying to get a feel of it in my gun. He, nor anyone else on the thread had an answer. I've heard of pressure spikes when the cartridge gets hotter, but not colder. Any advice would be greatly appreciated.
