Home Forums Hunting & Shooting Ask The Gunwriters Retumbo

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.

I read the same thing today....may have 1 lb. of unopened Retumbo, “for sale” .....to someone I don’t like! memtb

I'm just finishing up my first pound of Retumbo. I've used it in a couple of Senderos, a .264 Winchester Magnum and a 7mm Remington Magnum. Unimpressive accuracy results but good velocity in the.264, good accuracy and velocity in the 7mm. Nothing out of the ordinary as to high pressure indications. Outdoor temperatures have been from around 30 degrees to 55 degrees Fahrenheit.

While we're all curious as to the cause of the reported mishap, we'll likely never know.

I haven’t heard of pressure spikes with Retumbo. Has it been reported anywhere?

Curious what’s going on. Always thought it was a good powder.

DF

never had an issue with it, its all i use in my 300 rum 200gr accubonds at 3200 fps

I have never had a problem with Retumbo and have never heard of a problem like that. I would suspect something different like a wrong bullet in the box or somehow excess powder got into the case.

3100fps with the 190s and then 3129 with the 230gr round??? I think he had that puppy stoked with 91.5gr of powder, rather than the 86.8 he had been using. Lucky he's able to tell the tale.

Makes a fellow wonder. 3129 fps from a 230 gr bullet is moving right along, even for a 300 Rem Ultra Mag.

Guy

Have shot up a lot of Retumbo, never had any problems.

Still use a lot of Retumbo, in 6MM with 107 Match Kings good speed very accurate for long range.

Magnumdood, I think you screwed up some where with your reload. Rio7

Not a Retumbo issue is my bet.

What bothers me, there's no way to get a double charge with a bulky, slow powder like that. Even an overcharge will spill over the neck and you'll know.

So, it must be something else. Was there ever anything written after the fact with more info on what happened?

DF

My 7mag loves the stuff....71.5g to be exact.

An obvious overload.

I agree fully.

Would love to see the brass.

It's plain to see it's not Magnumdood from his post, he is talking about someone else.

Yeah, don't shoot the messenger...

DF

I use Retumbo in my 30X378 for years with 180's and have never had a problem. I also tried it in my Pre 64 264 Westerner but found better accuracy with Ramshot Magnum and RL-33

I had my bolt lock up on me with obvious low end powder charges. Turned out to be the brand of brass. Switched to another brass brand and solved the pressure problem. Took the charges right on up to 1 grain over book max and suffered no adversities.

Wonder if it could be some sort of under-charge? Or maybe the wrong can on the loading bench?

That's been known to happen.

If he was using a powder measure and the powder stacked, the next charge would spill powder everywhere and he would know.

I always look in the case before seating a bullet.

DF