I do all my hunting in 0 - 50 degrees. Most common temps are 30-45 degrees. I plan on working up loads to test for maximum loads with temps in 70's maybe low 80's. But I want to find my precision loads for hunting at about 40 degrees.

I've heard of some guys who put there shells in a cooler to test loads. So if it is 70 degrees out and my shells are around the 40 degree temp. Does this really work when your barrel is 70 degrees?

If this truly worked it would be awesome for testing consistency.


Thanks,
Adams

This would be a big waste of time; better using that time and ammo to practice shooting from field positions.
Anyway, your barrel temperature does not determine the burn rate of your powder.

For accurate testing of the load. Both should be at expected temperatures. Though probably very small differences... cold temperatures could affect barrel dimensions/ harmonics, and stock fit. These are not extreme variations in temperatures, and likely you’ll see little to no changes. Load development at 90 F and hunting at zero and below...testing would be advised! memtb

Work up, then check when it is actually at hunting temps at the range. Gun needs to be cold, too. (Probably won't matter unless powder is REALLY temp sensitive.)

2 cents

quote:

I've heard of some guys who put there shells in a cooler to test loads. So if it is 70 degrees out and my shells are around the 40 degree temp. Does this really work when your barrel is 70 degrees?

In all honesty this method would get you "close enough" to satisfy your curiosity.
Truly the best method is to shoot your pet loads at the range at the actual temps you will be hunting.
Where I live and hunt the temps could be in the 80's for Antelope season (even hotter for prairie dogs) and sub zero for some Deer and Elk seasons.
I'm lucky to have a range at my house so I get to shoot year round and have shot when temps were single digits and when it was in upper 90's in summer.
In all honesty I have never had a noticeable problem at any temps maybe I'm just lucky.
The most common powder in my arsenal is IMR4350 then a variety of other powders RL 15, 17, TAC, IMR 4895, 4064, H380.....
No issues here.

An issue I've given a lot of thought to is altitude. This never gets mentioned or written about.
I live around 6500 feet above sea level and have tried various calculations to determine how much lower my bullet will strike at sea level where air is thicker and obviously slows it down more.
Or how much higher the bullet will strike at even higher altitudes (my brother and I killed our Goats at over 13,000' in elevation) where air is thinner and affecting less drag.

In reality these topics make for interesting conversation and pondering but will not account for enough measureable difference of POI in the real world for average hunting shots on game.

I agree with dpcd, waste of time.

Dave

Yes, good for discussions over drinks; that is the extent of the practical applications of it. Shooting rifles under field conditions will mask any effects of temperature affected ammo. If any. Unless, as stated, they are very extreme like 100 degree differences, then maybe. Still, probably not.
Now, if you are bench rest shooting one hole groups. then, go for it.

I have tried it, but only checking if it will produce sticking extraction.

It did not.

I tri4d it in my 375/404.

Using maximum loads.

3 rounds were left by the rifle, at room temperature, in this case about 22-24 degrees C.

3 rounds we’re placed in the freezer set at 2 degrees C.

3 rounds were put on a concrete floor outside in the midday sun in Dubai, where outside air temperature was reading 48 C!

I fired all of them after them being in those condition for 30 minutes.

No sign of over pressure at all.

Powder was H4350.

The ones placed in the sun were hard to handle, because they were very hot!!

Other powders in other calibers might behave differently.

Something to ponder. Do you want a load that behaves well at 32 Deg. but that will give stick cases at 80 Deg.? For hard core target work I might try to customize but for hunting I will take function every time.
Oh, altitude does make a difference on long shots. A good ballistics program will show you just how much. If you sight in at sea level and then come here and hunt up at 10500' your zero will shift.
C.G.B.

I figured this was to good to be true. Have read about a number of guys who do this so thought I'd ask.

Thanks for input.

Adams

Propellant temp is indeed a factor in how much pressure a load produces, but the difference between 40 and 70 degrees won’t make a huge difference even in the most temperature sensitive powders. IIRC, based on the extensive tests Stan Watson did a few years back, he found significant differences with some powders at 110 degrees vs 32 degrees, and also found the Hodgdon Extreme line to be less sensitive to temperature than other powders.

Degrees of what, potatoes?

Magnum primer in cold. Magnum primers for ball powder, hot or cold. IMO.

http://www.shootingtimes.com/a..._st_mamotaip_200909/

I load to my rifles max minus one gr. and use them anywhere in the world at any time. I don't even concern myself with it and Ive never had a problem.

I use magnum primers in Magnum rifles and std primers in standard calibers..

I have not had misfire or a problem with any powder and I use a lot of ball powders wit std. 210 Fed primers such as H414, LVR, H380, H335, and a few others. I do suggest max or near max loads with ball powders, but I have nothing to back that up, just seems like a good idea to me to get the fire on the juice!!