8133 or retumbo

@tbrice23
Were the loads you used with 8133 hot or medium pressure.The reason I ask is some people said that RL-33 was a dirty powder and when used in low or medium pressure I found this to be true. But when I went with full pressure loads I found it to burn very clean.

I agree with that theory.
The load was up to 99% case capacity, it was up to pressure but not over pressured.( don't have a pressure trace but wish I did).

The 200.20x doesn't have a lot of bearing surface so it would not have built as much pressure as a 200gr Accubond or 200ELDX.

I might try 8133 again in the future with the Accubond or ELDX to see if the longer bearing shaft helps the burn characteristics with longer barrel time.

The loads in 300 rum at 88.5 were medium pressure didn't start to flatten primers till about 90.5 gr stopped at 91.ost accurate load was 88.5 although at 91 gr it was hitting just over 3000 fps on avg it wasn't as accurate.
Loads in my 7 mag I'm pushing about 2950fps avg with 63.5 gr reloader 22 with a 180 gr eld match I never chronographed my loads with 195 but they were very clean compared to the 8133 in the 300 rum but still not as dirty as some other loads I've run.

Retumbo for the win! My best load to date was worked up last week 94gr Retumbo, CCI-250, 208ELDM and newly annealed Norma brass. It's about 98-99% case capacity at OAL 3.692". SD 9, ES 22, Avg Vel 3206 fps, 26" barrel, excellent accuracy. Whenever the weather get decent again, a seating depth test will be performed?

I'm loading 28 Nosler and found Retumbo quite dirty (though most accurate) at a max load compared to h1000 and 7828. Have been looking at 8133 and RE33 but not been able to get any locally recently.

All these new powders coming out... and doing what H 1000 has been doing for decades...

I have a 28 Nosler, I have used H1000, Retumbo, RL33 and 8133, out of all these powders, RL33 is the most accurate in my rifle. The 8133 powder, after burning around 30 rounds, the first few patches came out black as tar, took a while to clean the carbon, I couldn't believe how dirty it was. The Retumbo did not show as much carbon fouling when cleaning.

I have not tried 8133, I did try Retumbo in the following, .257 Weatherby, 7mm STW , .300 Weatherby, and .300 Super. I didn't have much luck with it in my rifles. However in the above calibers plus the .300 Winchester Magnum Hodgdon H-1000 worked splendidly.

I use Retumbo in my .300RUM with 230 Hybrids.

This weekend, I confirmed zero and velocity after cleaning it and reinstalling the scope that had been on another rifle for some load development. This was after refouling it.





I run H1000 w. 215s in it as well. Right at 3110fps, and just as good of accuracy. A bit milder load too.

I don't consider myself an expert but have for many years reloaded for 2 300 RUMS. In my experience Retumbo is far and away the best for my application! I do not have my reloading data in front of me but do know I exceed the SAMI spec. Great results

I've never used the 8133, but really like the Retumbo in my 7mm Rem. mag shooting Berger 180 VLD's. I don't have the load data in front of me, but was a max load & my COAL was long as well.

I've used both Retumbo and 8133 in my 7mm. In my experience the velocities seemed very similar but I could get a little more out of the 8133 before pressure signs. In general I've heard that the double base powders used for temp stability are generally dirtier so this might be a mute point, but contrary to what several others have written, I have found that 8133 shot cleaner than Retumbo. Kind of strange. It's through a chrome-moly tube, so I'm wondering if those who saw Retumbo shoot cleaner, stainless barrels or chrome-moly? Might be a new thread I'll have to start. Either one shot great with very similar velocities around the accuracy node. Both also similar in temp stability as far as I can tell. Could be splitting hairs with these two powders, but for what its worth I personally have moved from Retumbo to IMR 8133.

I just got a can of 8133 for the 26 nosler,no load info yet from any sources other then to say it is on par with rl33,i got it for the copper cleaning aspect of it plus from what i hear about the eld x I'm going to need all the help i can get.

Justin Todd said:

Just want some thoughts on which one would be the better powder. I have 8133 and have been using it in my 300 rum but have always heard Retumbo is the way to go. I also shoot some heavies in 7mm rem mag also but haven't done any load work up with 8133. I've never shot Retumbo deciding whether to buy an 8# can when it's available or just stick to the 8133 would like your thoughts.

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Retumbo all the way. I get 3,400 fps with a 180 AB in my long throated 26" 300RUM and it keeps groups in the 3/8 moa

The 200AB and ELDX runs at 3250 with 1/4-1/3 Moa with the ELDX