Summer pressures

[head2h2o]

Just wanted to confirm what I think I am seeing with some that have been reloading longer than myself. Back in the winter (such as it is in south Texas) I was getting the following with this set up.

Rem Brass
175 gr SMK
CCI 200 LR primers
45.0 gr BL-C2
2645 fps
24" Krieger, LR 308
No signs of pressure
Avg temp at the time was probably in the 40-50 range.
Easily sub MOA groups.

Yesterday, I shot this same load in the 95-100 degree temperature with flyers every where. 3 MOA was good and there appeared to be signs of pressure around the primer. A fellow shooter shot the gun and was getting about the same results.

Is BL-C2 known to be temperature sensitive like this?

Is there a place I can find the powders that are most temperature sensitive listed?

What would be a good option for a powder that would allow me to keep the speed in the same general area while not having the variances that I feel like I saw yesterday between different temperatures?

 

[BobinNC]

Re: Summer pressures

See this post:

BLC2 Temperature Sensitivity

Most ball powders are know to be temperature sensitive. Hodgdon developed their Extreme lineup of powders to combat this problem.

As a temp solution, you could put your ammo into a zip lock bag, and carry it in a small cooler with some ice, on hot days.

Bob

 

[crumpett]

Re: Summer pressures

I am sure that there are any number of less sensitive powders, RE-15 has worked really well year round for me.

 

[Unsichtbar]

Re: Summer pressures

Rl 15 increases about .7 ft per degree it can put you in a high preasure area if your loads are stiff. Which is one reason the Military looked for a different power for some of there loads. So people like Varget I have used that also but the best I have ever used is the new IMR 8208xbr plus it has othe benifits. I shot in brutal heat yesterday. Corrected for DA only round dead on, IMR says temp. stable to 165F, I froze some 32F others under a heat pad 125F it works.

 

[deer assassin]

Re: Summer pressures

i work my loads up in the heat

i loose a lil speed in winter but this works for me

 

[head2h2o]

Re: Summer pressures

Bob,

I took your advice and put the rounds in the freezer before I left and kept them on cool packs until just before I shoot them. It was stacking rounds right on top of each other just like it did in the winter. I think I am going to get through what I have of the BL-C2 and start looking for another load, probably something with Varget. I had initially had some good groups with that also.

Thanks again.

 

[BobinNC]

Re: Summer pressures

head2h2o,

Glad it worked out for ya.....

Bob