Mace -
Howdy !
FWIW -
I used to shoot RL-22 in a 6mm wildcat of my own design, that has 51.2gr H2O capacity.
After reading that RL-22 " burns " really hot, I wanted to go w/ a different powder that does not have so high combustion temperature, and one that is also temp insensitive.
I was able to obtain 1lb bottles of RL-23, RL-25; and RL-26. Spent a lot of range time doing a 3 way powder run-off, to see which powder would give me best accuracy, useful accuracy; and safe pressures.
RL-23 & -25 are made in Sweden. RL-26 is Swiss-made.
Reloader says that RL-23 is made w/ " TZ " technology, to be " exceptionally consistent.... across temperature extremes. " The label says RL-23 is a " Smokeless Magnum Rifle Powder. "
RL -25 is labeled as being a " Smokeless Heavy Magnum Rifle Powder " that is
" ideal for over-bore Magnums ".
RL-26 is manufactured using what Reloader calls " E1 " technology, to allow
" extremely high velocities in Magnum cartridges. "
Testing all 3 of these RL powders in my " DEEP 6 " wildcat using Sierra 6mm 95 T-MK:
- All three powders gave higher max charges velocities than what I saw when shooting max charges of IMR7828 and RL-22 under the 95MK. With those powders/charges, RL-22 very nearly filled the case, while max charge of IMR7828 DID fill these case to base of the bullet... all with safe pressure. RL-22 burning hotly and IMR7828 being discontinued prompted me to seek out a new and temp insensitive powder to use, and the 3 RL powders looked like good candidates.
- I was surprised that the velocity results were not " linear ".
- While closely monitoring case head expansion and other pressure signs, I started the tests thinking that velocities would progressively increase as the charge weights went up.
I also started out thinking each progressively " slower " " burn rate " powder would have a progressively higher max charge wt than those faster in burn rate.
- I noticed that RL-25 max charge wt was a bit heavier that max charge wt for RL-23, which was expected. I was not surprised on the velocity results that showed RL- 26 w/ the highest charge wt and highest amount of case fill.... gave the highest obtainable velocity of the 3 powders.
- What I did not expect to find, was that RL-23 ( and not RL-25 ) gave the second highest
max velocity.
- RL-26 max charge load velocity was 50+ fps higher than the second place max charge of RL-23 load. The same RL-26 max charge velocity was 157 fps higher than the RL-5 load.
I had previously read someone else's reporting on the same result, that RL-25 obtainable velocity was lower than obtainable velocity when shooting RL-23.
ATK ( owns Alliant powders ) says that ..." performance of RL-23 is similar to RL-22...
in general burn speed terms." They also report that RL-26 is not quite as flat on temp insensitivity as is RL-23, which is made using " TZ " technology; but is very close.
- My test results showing RL-26 giving the highest velocity is consistent w/ the manufacturer's claims for it. RL-26 uses the same special coating that they use on Rl-17.
I did so much range testing, that my can of RL-26 has only 20. 44.2gr charges left in it.
And, my RL-23 and RL-25 bottles are themselves well down.
* Pressed for adequate prep time for shooting groundhog this year, I chose to use RL-26 because of the higher velocity providing flatter bullet trajectory. I loaded cartridges and went afield w/o even doing a 100yd 5- shot group test... which was a first for me !
I also had dropped the max charge of RL-26 I used by just .2 grains, out of force of habit for what I often do as outdoor temps rise over time. Plus... I pushed out seating depth for the field loads some.004" beyond the c.o.a.l. I had used when doing an accelerated scope zeroing. I did manage to take some groundhogs with the expedited RL-6 loads.
What limited group shooting I did accomplish with the 3 powders was inconclusive as far as best accuracy goes, since things like powder charge wt, seating depth; and even scope zero we simultaneously in flux. Not the best way to things, but again.... I was pressed.
Y.R.M.V.
My point:
If you can locate any... RL-23 and RL-26 powders might deserve a look, but locating these has recently become more problematic.
I DK If this helps you any ?
With regards,
357Mag
