Tried RL-33 in three different chamberings today

Iron Worker: I would imagine you would be in the 3500 fps neighborhood. I would certainly work up to the max I used.

I said I wouldn't do it but today I tried some RL-33 in my 300 RUM with the 230 gr target hybrids.
I have a nice 27" lilja SS but unfortunately it has a 1 in 12 twist. I wanted to try the 230s a while back so I rechambered a 24" 300 win mag ss Rem takeoff. I had a load with 88.5 gr of H1000 vel 2860.

Didn't change anything except the powder. Started with 90 gr and worked up. Temperatures were 85-90 degrees. Here are the results so far:

90gr 2665
92gr 2745
94gr no reading cardboard shades moved had to wait for next ceasefire to adjust
96gr 2875
98 gr 2925
100gr 3001

No signs of pressure, no bolt lift issues, primers look good etc. Will start when range opens and temps are in the low 50s. Will chrono the 100 gr load again for comparison. FYI the chrono was working perfectly the 308 and 284 shot the same velocities as the last few times.

Will report back tomorrow.
 
Thanks for getting started with Reloader 33. I have been waiting for it to appear on the local shelf next to Reloader 25 at Sportsman's Warehouse but it has not yet.

Thanks to a friend who paid the Hazmat Fee, I have a pound of VV N-570 to test and have some preliminary encouragement. VV N-570 is just a little bit slower than Retumbo. In fact I would suggest starting with Retumbo maximum loads and expect to squeeze another grain in the case before the primers get loose or puncture.

Here is my latest range data: 6.5 WSM using Norm 270WSM that has multiple firings and Fed 215M primers. Chronograph was 16 ft from the muzzle. Remember that the 1885 falling block has a 28 inch Krieger barrel. The twist is 1 in 8. 140 gr Sierra Matchkings HBN coated.

Control 67.0gr of Retumbo 3267 3260 hot load 2 shots
I like 66.0 gr better.

VV N-570 67.0gr 3236 Primer looks just like Retumbo with the same charge.

68.0 gr 3302
68.5 gr 3314
69.0 gr 3332 What is all that smoke coming out of the action? Oh the primer was pierced.

I would expect Reloader 33 to do well in my two 6.5 WSMs with heavy bullets since Retumbo has been the go to powder with 130 ABs and 140 gr match bullets.

VV N-570 is very coarse stick powder. Each kernel weighs 0.08 gr which is a drawback in getting similar charges. Retumbo is much easier to weigh. Please describe Reloader 33.
 
I tried R-33 and N-570 in my 6.5-300wm today too. N-570 with 1 grain more than my Retumbo load gave me 45fps more velocity. With 2 grain over Retumbo I got sticky extraction. I shoot 70grs of Retumbo with a 140gr Amax. I loaded 74grs and 75grs of R-33 also. 74grs was right about where 70grs of Retumbo was for velocity and 75grs was up 50fps. With the 75gr load the primers were just flattening out but there wasn't any extraction issues.
 
IdahoCTD:

If I read this right you got approx 5 fps more than N570 using RL-33 ? You also said you didn't have any signs of pressure with RL-33. Are you going to try more powder till you get pressure signs? Thanks for contributing to this RL-33 thread.
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As for a description of the powder...it is coarser than RL-17 but is quite dense like RL-17. It only takes a kernel or two to make the elec scale move 1/10th of a grain in weight when trickling to an exact charge weight.
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I went out again today to continue the 300 RUM testing with RL-33 and the 230 Berger target hybrid:

Shot the 100 gr load this morning in 60-70 degree weather. The average velocity for four shots was 2975 fps. This compares pretty close to yesterday's two shots averaging 3001 at 85-90 degrees. Will need more rounds to conclude if the powder is temp sensitive as well as cooler mornings. Az just won't cooperate with cooler weather yet.

Continued with more powder:

101 grs 2983 fps This is the first increase that didn't show a 50-70 fps increase in velocity. It would appear that there is nothing more to gain by increasing charges

102 grs 3016 had a tiny amount of bolt lift resistance.
Didn't try any hotter loads.

For my rifle 100 gr is the max I'll shoot. It was the most accurate too.

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I intend to get out on Sunday or perhaps later next week for sight in and further chronographing.

I don't have any other rifles that are candidates for this super slow powder. Look forward to reading about other loader's rifles and results.

I am very interested in reading about a 7 RUM and more on the 6.5 WSM. Also wonder if any powder bridging issues could surface with some of the larger cases which has been reported by Kirby Allen in the past.
 
To me it seems like N-570 is more dense than R-33 and it's much more coarse. 1 or 2 kernels of N-570 will easily jump .1 of a grain. R-33 was similar but not quite as heavy IMO.

I will try 76grs and I might load one at 77 just to see how it does. I'm definitely going to load up a few at 75grs to check accuracy again.

I might have to dig out my .30-378 IMP. to see how this R-33 does. When I built it years ago many of these powders weren't available so I got to burn good old WC872 charcoal.
 
Interesting VV N570 is coarser. Never tried any VV powders.... Would love to hear how that 30-378 would perform with RL-33. What bullet would you try?
 
N-570 is a lot like IMR7828 prior to the short cut version.

I'd have to try something besides a VLD most likely. It pushes them too hard. It will shoot 150gr Nosler BT's over 4000fps. I think it was pushing 210's over 3400fps last time I tried.
 
You could try the 230 gr target hybrid. Thicker jacket of bearing surface than the hunting VLD plus heavier weight will slow it down. Imagine a .380 G7 BC screaming from your rifle. The OTM 230 gr hybrid did a great job last year with Broz and his son. From what I have read the taarget hybrid and OTM 230 gr bullets are very similarly constructed.
 
10-7-2012 Continuing with RL-33:


257 Weatherby moly 110 accubond:



83 3625 which slightly faster than old load with RL-25
83.5 3674 fps shot well two shots were same velocity
84 gr 3704 fps shot well two shots were same velocity
84.5 gr 3735 slight signs of pressure on one case of four this is max case capacity with drop tube

This makes a 91 fps gain over a max load of RL-25



6mm-284 non moly Berger target hybrid

worked up to 64.5 gr which showed slight lift with very tiny shiny spot on case head from Rem 700's ejector hole. (This is with 8 times fired lapua brass)

62.5 gr 3376
63 gr 3414
63.5 gr 3453
64 gr 3485 fps excellent accuracy
64.5 gr 3535 a bit warm max case capacity using drop tube


Old velocity with Retumbo was 3307 which was the highest charge of powder without pressure issues. RL-33 yielded a 178 fps increase!




I will be replacing the 6mm-284 load if it continues to work well in the next few shooting sessions. Ditto for the 257.

I look forward to hearing on what others get with similar over bore cases like the 7 RUM, 257 STW, 6.5-300 weatherby, and many of Kirby's magnums.
Love the discussion all.. I am loading a 257WM as we speak and find RL33 interesting as well as having a few #'s. I was working with RL22. I have not fired any yet out of my rifle, but did load a cartridge with 82 grains and a 110 grain Hammer to see how compressed it was and if the bullet would move. I did a light crimp and will see how it goes.. AZ, how was the accuracy with the RL 33 in the 257? Many thanks GMCQ
 
N-570 is a lot like IMR7828 prior to the short cut version.

I'd have to try something besides a VLD most likely. It pushes them too hard. It will shoot 150gr Nosler BT's over 4000fps. I think it was pushing 210's over 3400fps last time I tried.
No, N570 is much slower than any cut of IMR 7828. BTW IMR 7828 ,it's my go to powder for my 257WBY
 
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This is a VERY old thread! So old that the 257 barrel I talked about has been replaced with a lighter profile SS 3 groove Lilja. I also switched to the 115 Berger VLD hunting bullet. Accuracy is great with the second barrel which I chambered myself.

It likes 82 grains of RL-33. This is with a custom reamer with .100" freebore and a 1 1/2 degree throat angle in a 27 1/4" 3 groove lilja with moly coated 115 berger velocity is 3642 fps.

This particular reamer has made 7 rifles all with 3 groove liljas. Every owner is happy.

Since the original posting I also wore out the 6mm-284 barrel. Messing with another and still using RL-33.

Also stopped using RL-33 in that 300 RUM. Seems as I am now in my 70s the excessive recoil with the 9 lb rifle seemed a bit much for the style of elk hunting I do. I moved to H1000 for a moderate load with the 230 Bergers. I shot a nice 6 x 6 with that combination at 156 yds. Great performance, nice exit hole and an immediate death.

The irony of this year none of my centerfire rifles will be used to hunt big game! Just filled a coues wt tag using a muzzleloader. Have a cow elk hunt in NM with muzzleloader. AND the only tag we could get was a HAM hunt for javelina. (handgun, archery, muzzleloader)
 
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