Home Forums Reloading Big Game Rifles RL 22 and temps

As I get more and more into reloading, I find that in almost all my rifle/bullet combos, RL22 seems to work well for me. How is this powder when it comes to how sensitive it is to lower temps? no I didn't break out the chrony the other day when I was shooting at -12, so I'm asking.

Loads developed and fired around 60� and chronographed with the same equipment at 12� out of a 338 WM lost 200fps for me. In the same rifle and cartridge, there was reduced velocity as temperatures dropped. YMMV

I worked up loads with a 7mm-08 using RL-19 and a 139 bullet in 80 degree weather. Near a max load of RL-19 (not RL-22 like you ask of) yielded about 2650 in the 80 degree weather and exactly 2400 in 36 degree weather last weekend...

Pretty eye opening...

YMMV...

This is one question that I too have been interested if finding out what's up. I've read posts where some have found extreme differences and others have not.

REL 22 is the powder I've had good results with in my .300 win mag for both accuacy and velocity. I get about 3040 fps with a 180 bullet in temps around 50 to 60 degrees.

I have also questions about changes in the formulation for REL 22 over the years. I read where they might have made changes for less lot to lot variance and possibly less tempature sensitivity. It's sometimes hard to decipher internet rumors from fact. If anybody knows the facts on this, please tell.

Bobski - When did you do your testing?

handwerk - Did you have your rifle sighted in before your last test and did you see a shift in POI?

The big concern for me would be shifts in POI at lower temps and with a difference of 200fps that question is answered.

If anybody else can post info on this question, please include when you did your testing.

Thanks,

fish head

As a side note, one interesting thing I read while roaming the internet was from Vihtavuori's website. It mentioned that tempature sensitivity varies with a given powder depending on which cartidge that it's used in.

I thought this was an interesting fact since it's coming from a manufacturer that's based in a cold climate.

fish head

What difference would it make "where" and what does that contribute to temperature sensitivity? Lousy question, but the original readings over an Oehler 35 were at the El Dorado Rod and Gun club range in California and the Folsom Gun Club ranges at Sacramento Shooting Center. The cold temps were clocked at Gardiner, MT and Cody, WY.

FWIW, 4 hours after the Gardiner test an elk was taken at 175 yards with the bullet hitting within 2" of point of aim. The most shift would take place a much longer ranges. This is the elk:

Bobski -

I didn't say "where" I said "when" - as in what year.

Chill out - (pun intended)

fish head

I realize that a slight shift in POI, in the real world, as in shooting an elk at 175 yards, it does not make a difference. Nor does having a sub MOA rifle or a rifle that shoots two inch groups. Or for that matter whether your rifle is sighted in at 100 yards one inch high, two inches high or three inches high.

This is a reloading loonyness subject.

If I can use a powder that isn't affected by tempature - all the better. I reload to get the most accuracy possible.

Nice elk, BTW.

fish head

I believe Denton has shown this with Varget.

My apologies; LOL on the pun.

Don't recall date on that elk but the testing remained ongoing until I decided the temperature tolerant powders like Hodgdon's and Ramshot's would eliminate one more factor. The VihtaVouri N500 series were originally touted to also be temp tolerant but I found in a 338 WM that the N100 series was more so than the other. The test started about '97 or so until I reached my own conclusions about 6 years later and settled on mostly the Hodgon Extremes, mainly H4350 and H4831, with one or two rifles using Ramshot Hunter and Magnum, all of which remain the same velocity in my rifles down to 0�.

I have heard from a few that RL19 and RL22 are in fact temp sensative. According to Alliant, RL17 seems to be far less temp sensative.

For all hunting loads, I prefer either the RL17, H-4350 or the VV N165 for my 300 WSM. Much better velocity consistencies going from warmer temps to the far colder temps.

I chrony'd the 140 AB in my 270 Win at 80 and 50 degrees and obtained a 5 shot average difference of about 11 fps. I'm going to try to hit the range this week sometime with some other rifles, so I think I will load up some more AB's and see what I get in the teen and 20 degree temps we're having.

As said it depends on the cartridge but in my limited experiance there is not enought difference in most cases to worry.
I ran a small test here with R22 in a 6.5x55 useing a Pact chrono and RSI pressure trace..

What's interesting about this whole subject is the different results people have had with a given powder and different cartridges/loadings. Some find enough variance with a particular powder to make a difference and others not - depending on the cartridge/load being used.

It also seems to make a difference in what temperature range is being used. I recall looking at Hodgon's website where they showed their findings in IMR4350 vs H4350 in a 30-06 load (I can't remember what bullet weight). From 50 degrees to 0 degrees, IIRC, there was a relatively minor difference in drops in velocity with the two powders. Going from 50 degrees on up then there was a significant difference, with the H being far less sensitive. IMR 4350 has the reputation for being temp sensative but what Hodgon had published, was that it wasn't so bad at lower temps. ? ? ?

I guess it can depend on whether someone is considering a load/powder for an African safari or a load for a late season Montana elk which powder is best.

The claims of a given powder to be totally temperature insensitive depends on ........

Granted, there are certain powders that show far less deviation than others, or at least, to a lesser degree.

All this is based on what I've read and not my actual testing or results.

Thanks to those that have posted actual results vs my internet/inexperenced babbling. On this subject I'm here to learn something from those of you with actual experience and results.

fish head

I was writing when O'l Joe was posting.

Here's a prime example of what I asked about or commented on in my earlier posts.

O'l Joe's tests were done in 07 with a 6.5x55 and REL22. Temps from 83 degrees to 27 degrees. Difference of 20 fps.

Bobski's tests were done in 97 or so with a 338wm and REL22. Temps from 60 degrees to 12 degrees. Difference of 200fps.

The results are very different and substanial enough to make one think twice about using REL22 in a hunting load without actually testing it in a given cartridge.

Is this a difference from a change in formulation or just two different cartridges/loads?

Inquiring minds want to know.

fish head

I do a lot of my load development in the summer, but much of my hunting in the winter. In Michigan that translates to high-80s or hotter in the shade, down to 0 or lower during hunting season.

This summer I worked up a varmint load through my 257 AI using IMR-4350. It was crankin' a 100 gr Speer Hollow Point to 3330 fps. I went out this past Sunday during 27 degree weather and although it still grouped well that load was printing over 120 fewer fps. I didn't have that rifle zeroed for that load so I don't know if it had the same POI or not.

My '06 loves RL-19 so I'm interested to see what the deal is there. To my way of thinking if the load produces the same group sizes in both types of weather and you sight your rifle before each hunt this is a non-issue, but that remains to be seen.

Good discussion!

PS- I'm testing RL-22 in my '06 and 257 AI tomorrow and it'll be a cold one... makes me nerveous to pick up "max load" info derived from wintertime tests and transfer it over to summer, you know?

On the other hand, trying out loads of RL-17 through 338-06 and it is comforting to know that THAT info will be fine...

I'll add one more thought. Differences in velocity would certainly correspond to a drop in vertical POI at distances. At some point though, an extreme spread in velocity would seem that it might start to affect the barrel harmonics enough that POI could start to go away in any direction and or group size. From what I've read though, group size does not seem to be affected that often, if at all.

It of course would depend on how finicky a given rifle is. My thin barelled 30-06 will throw different loads all over the place. Any small change in loads makes a noticable difference in POI.

I make a point of sighting in my rifle in the cooler fall temps to avoid, as much as possible, a shift in POI from temp changes.

Loonyness now has me searching for a powders/loads that eliminates this whole issue.

Reloading is fun for someone with a tendency towards OCD.

fish head

The other variable that has been hinted at on this thread is the date of manufacture of the RL22. My current powder inventory ranges from square, steel cans of Hercules powders to lots with manufacturing dates of 2008. It would be easy for many of us to have a 10yr old lot of powder on hand.

If anyone who posted the above data knows the date of manufacture for the lot tested, adding it to your post might (or might not) add some interesting insight.

405wcf

But RL22 is just so accurate! I like Hodgon powder, but there are a few calibers where RL22 is just the cat's meow!

338 Win Mag with heavier bullets being one of them! Depends on temp swings and individual use.