After a lot of deliberation on the rumors of RL22 being one of the most temperature sensitive powders out there, I still decided to try it in my .300 Winchester Magnum. I wish I would have tried it a long, long time ago. Anyway, I worked up a load this summer/fall and got a load that shoots sub m.o.a. consistently and averaged 3,184 fps for 6 shots fired through the chronograph on a nice sunny day of about 75 degrees.

Fast forward now to December. Saturday the high was 24 degrees here in town. I was up on the hill(another 1,000 vertical feet) at about 10:30 in the morning, so I am being conservative in saying the temp was around 20 degrees. Fired six more shots through the chronograph and came up with an average of 3,146 fps.

Conclusion: For a 50-55 degree spread my gun dropped 38 fps in average velocity. After this little test, I am glad I viewed the temp. sensitivity issue more as marketing hype than fact.

Hope this little bit of information is useful.

I've had great luck RL22 as well.

My Browning 1885 30-06 works very well with a compressed load of Rl22 and a 165 BT. I get the same vel. as I can manage with 150 grain bullets and its very accurate in this rifle.

I've also had good luck with limited testing in a .300 RUM with 165's.

It's one of my favorite powders.

300winnie, thanks for the test report, but were the cartridges cold before shooting, or did they just come from your cozy home at 70 some degrees? If the powder wasn't as cold as the ambient temp, it doesn't help much.

Now that you have realized how much you missed by not using RL-22 in the 300, try RL-25. You will be using RL-22 for yard fertilizer.

good point wrongtarget...

wrongtarget and whiplash,

I had the same question posed over at 24hourcampfire. Definitely a good question. Here is the answer:

Good question. I had thought through this as well.

The ammuntion fired on Saturday was compiled at the same time, with all the same components (lot numbers of brass, powder, primers, bullets) as the ammunition fired in September.

I put the gun and ammunition in the back of my truck (cased of course) for the ride to the hills to fire it. It was in the back of my truck for approximately 2 hours before I pulled the trigger on the first one. Both gun and ammuntion were sufficiently at ambient temperature.

The first round out of the barrel clocked at 3,144 fps...very close to the average.

My Son in Law and I did something similar this summer. Worked up a load with 160 Accubonds and RL-22 in his 7 MAg. with the daytime temp. well over 90 deg. Not having access here in Kansas to cooler high elevations, we put some of the rounds in his freezer for a couple of hours. I'm not sure what the freezer was set at, but should of been somewhere below 10 degrees. Anyway we shot alternating hot and cold rounds. The cold ones averaged over 100 fps slower than the hot ones. Our test was more extreme in temp. variation so that may explain the difference from your test. H4831SC only dropped a few fps. Ramshot Magnum was about the same as RL-22.

A 90 degree variation in temperature causing 100 fps change would not be a lot IMO. I am more interested in whether group sizes and POI remain the same than the velocity. That is why I don't use a load that shoots .3's at 69 grains and 1.2 in. at 67.5 grains of the same powder. Temperature changes causes the same resulting change in POI a lot of the time.

Temp sensitivity for me is not air temp.

If I shoot 5 hot rounds rapidly and then leave the next round in the chamber for two minutes, the primer will fall out of the 6th case in my .308 Sav 99.

That was on a cold day.

So it would only take 4 shots on a really hot day?

What does it all mean?
Air temp is not the problem nor the solution.
The problem is I need to back off 2 grains, and I did.

This is not a scientific response but a personal observation. I sighted in my 300 win mag and my 30-06 at 72 degrees and 250 feet above sea level. Both loaded with H4831 the 300 was getting 78.5 grains with a Nosler 180 Partition and the 30-06 60 grains with a Nosler 150 Partition. Both had Winchester LR primers. Both guns were running 3150 fps. both guns were in hard cases, both had Leupold scopes and Leupold mounts, Remington 700s in McMillian A2 stocks. I have no control on what the Airline did to them between North Carolina and Saskatoon. Went to the range in Green Lake on day of arrival -14 degrees. The 300 showed little change at 100 yards + 5 inches and was +3. The 30-06 shot 6 inches higher and the scope would not adjust. Adjustment moved but crosshairs stayed put. Third day in field tempertature dropped -40 and when bolted round was ejected bullet remained in rifling. Another hunter had a bolt freeze up on him. When hunting in extreme weather ie: cold I recomend degreasing, and test firing daily. A piece of electric tape helps keep the bore dry and ice free. Moisture from condensation builds up inside both the action and barrel. There is nothing worse than sitting all day in sub zero weather and have a trophy walk by and your gun not work.
I can tell you at -40 you don't want to touch bare skin to any part of your gun. Fingers will stick to the bolt just like your tongue on a freezed shelf. Your cheek has perspiration on it, it will stick to the stock like super glue.
Longshot

quote:

Conclusion: For a 50-55 degree spread my gun dropped 38 fps in average velocity. After this little test, I am glad I viewed the temp. sensitivity issue more as marketing hype than fact.

I've used R22 in 7RMs from 80-90 temps down to 20-30 temps and never have I found much of a difference in performance.

My main gripe w/ R22 is lot to lot variation not temp sensitivity. When you find some great loads w/ R22 5lb jugs are a must. You have to work back up every time you switch lots to be on the safe side.

Reloader

quote:

Originally posted by Reloader:

quote:

Conclusion: For a 50-55 degree spread my gun dropped 38 fps in average velocity. After this little test, I am glad I viewed the temp. sensitivity issue more as marketing hype than fact.

I've used R22 in 7RMs from 80-90 temps down to 20-30 temps and never have I found much of a difference in performance.

My main gripe w/ R22 is lot to lot variation not temp sensitivity. When you find some great loads w/ R22 5lb jugs are a must. You have to work back up every time you switch lots to be on the safe side.

Reloader

That's been my experience with it too!

With a powder that varies lot to lot, have you ever tried setting your measure by volume rather than a certain weight? A lot of times I can set my measure to a certain setting, change lots and the velocity is practically identical, while the charge will be 3/4 grain off. Has anyone else experienced this? If you haven't tried it, I'd like for some others to try it and report back.

quote:

I've had great luck RL22 as well.

Same here!

I shoot RL-22 with .257 Wby, .270 WSM, .300 Winny, .340 Wby, .358 STA and .416 Rigby. I have used several pounds each year since it came out and have shot it from well below zero in Colorado and Alberta to 95 degrees in the Selous of Tanzania, and have never experienced any perceived difference in POI. I shoot three days per week year around regardless of temperature, snow doesn't stop me, rain does. I chronograph 99% of all shots. At present I have on hand 18 pounds of one lot, 10 pounds of another lot and 5 pounds of another. I plan on shooting it for a long time. Arguements about it being temperature sensitive are just that in my opinion. Good shooting.

Have not done any temp testing, but can confirm the Lot differences. I have seen the same pressure from a 68.5gr load and a 70.0gr load that were from different lots. Would never expect a 1.5gr difference, but who cares, just be careful like others suggested, the velocity and accuracy are worth it.

Deke.