RE25 temp sensitive?

[velvetant]

RE25 temperature sensitive? still testing but looks good so far.
During the summer I worked up a load for my 25-284 with RE25 and a 115 NBT.
I loaded up a batch of 25 rounds
10 rounds@95 degrees gave me 3122 fps ES of 12, I shot these this summer.
10 rounds@35 degrees gave me 3108 fps ES of 11, I shot these today.
Both shot from the same batch to keep things as consistent as possible.
I really wanted to test them at negative temps but was not able to get out.
Still got a few months of cold so I should be able to get it done.

YMMV

Randy

 

[DrMike]

Randy,

It'll be interesting to see your results. I have not found pronounced temperature sensitivity. I am conscious that when I work up a load in winter to throttle back in summer and work up again to verify that I'm not generating excessive pressures. With the exception of some seriously overbore cartridges (7.21 Lazzeroni, 7.82 Lazzeroni, 30-338 Wby, etc.) I have not found a serious problem. It is more a matter that I am conscious of slight variation in velocities.

 

[JD338]

I have limited experience with RL 25 but I have not had any problems with it. Accurate and consistant.

JD338

 

[onesonek]

At that temperature range and difference,,,,I think you can call .23 fps (avg) per degree drop fairly temp insensitive. It was a few years ago but not all that long,,,where I read some article, that with some temp sensitive powders one could expect up to 3 fps per degree change. I don't remember which powders they were,, but know that the Hodgdon, Alliant, and Vihtavouri powders I use were not listed. I suspect you will not see much more loss than the avg. .23 fps per degree when venturing out at sub zero temps. And with your loading practice's keeping you close to single digit ES,,I'd say you are doing quite well at keeping things consistant.

 

[khh]

Is the ammo you testing cold or just the air temp? I shot RL22 in a 300 Win Mag and got close to 100 fps difference but that was when I left the rifle and ammo in my truck over night in sub zero temps. I had already chronoed the ammo in the summer and just happened to chronograph it again that day. I think if I would have taken the gun and ammo at room temp out into -10 degree it would have shot the same as it did in the summer. The lost of velocity didn't bother me that much but the change in POI did. I switch to Hodgdon extreme powders for extra cold temps. Now having said that before I found this out I hunted in subzero temps in Saskatchewan several years and even made a 250 yard shot with RL22. If I wouldn't have stumbled across it I dought I would have noticed any difference. KH

 

[Guest]

I load RL25 in my 300 Ultra Mag. Use 95 grains to propel 180 AB AT 3372 fps. I worked this load up and shot it while temps were in the low 80's here in Tennessee. I have not clocked it since then, but did shoot and check the gun prior to my Elk Hunt when temps were in the 50's. Printed the same place on paper as it did when temp's were in the 80's. I was more concerned about the warmer temps. due to pressure build up. I do not have any pressure issues except this load is with new brass, not re-sized brass.

Don

 

[Greg Nolan]

I use Rel 25 a lot in the RUMs and I load for max. I have had no pressure issues from 100+ here in California to 15 in the Rockies. I've chrony'd my loads and checked my trajectories out to 500 yards and I've never had to adjust for temperature only altitude so I do my final sight in at 5,000 ft and it keeps me good enough up 10,000 ft. That also verifies I'm not pushing my pressures too high for reliability and safety.
Greg

 

[velvetant]

Is the ammo you testing cold or just the air temp? KH

Both, and my rifle.
I tried to simulate actual hunting conditions the best I could

 

[Ridge_Runner]

alliant powders are double based, all double based powders are more temp sensative than single based powders due to the fact they contain nitroglycerine.
I've dropped re-22 from my loading not because of the temp sensativity but because of lot to lot variences.
RR

 

[Dicko]

Randy that is good news.
I don't think I'll get to the low temps where I am in Australia but definitely the hotter temp seems fine for me.

It gives me quite good velocity too - 3127fps with 120gn bullet.

Regards,
Dicko.