As a new 458 owner and the weather heating up I'm wondering what those who have been there consider African heat? I won't get too many days in Michigan to see if my loads are too much in hot weather. 90F hot enough?

Makes a huge difference where you go and when. Namibia and Zimbabwe in June were 70s-80s when I was there. Look up Mrlexma's report of his elephant hunt in Ocotber in the Caprivi Strip -- way, way over 100. I understand that the Zambezi Valley and parts of West Africa can get very, very toasty as well.

Edit: Here is Mrlexma's report -- they got temps of 128+.

Most folks don't hunt Africa in the truly hot months. If you are ok in 90deg, you are probably fine at 100deg.

It's not really the ambient air temperature that will make big a difference in your loads; it's how hot the chamber and ammunition get.

I hunted Tanzania in 100 degree heat, and my loads exhibited no pressure signs at all. Keep the gun in hand, not sitting in the truck's rifle rack or slung over your shoulder with the sun beating on it.

George

makeminestainless

I have hunted here in Australia regularly over 100c and even up around 110+

Never had a problem although I am conscious of
possible issues MAY arise so keep my eyes and ears open.

One thing I did find is that the ammo (and guns) do get damn hot, even in just your ammo belt.

100/100 is houston HOT...

not that I have any firsthand knowledge here, but If there were a safe way to heat your ammo up to ...(somebody chime in here)... 130F and work a load up using that temperature as a constant for your load development, you would have no worries about pressure.

As George notes, the real problem is the rifles and ammo sitting in the sun. Our hunting trucks are invarably designed to ensure that the metal work of the rifle is too hot to touch by the time you take it down (in the summer at least). Also, here in Zim in september/october there is virtually no shade so the rifles sit in the sun, or get carried in the sun.

I think some reloaders don't understand (and I'm no expert either) the protocols used by testing labs before ammunition meets safe parameters. One of the testing protocols involves heating up the ammo before firing it and then measuring pressures. It's easy to say you can get an extra 200 fps by handloading. Heat up your ammo to 120° before firing and see if you still remain under SAAMI or CIP max pressures specs.

Never having been to Africa I have to guess and I suspect it has strong radiant heat...from the ground like Australia?

For example a 100 *F in Sydney is totally different to 100 *F in our inland. With the inland the mudguards of the car will be much hotter as will the rifle.

I have shot many times where the ammo is to hot hold and also the scope is a bit too hot to touch.

I think the Australian powders that Hodgdon markets as Extreme probably do work. The reason I say that is you simply don't hear the stories at the range from people who have come back from a shooting trip and are talking about belting bolt handles open. However, that use to be quite common. Also, articles in our gun magazines on temperature and reloads are nowhere near as common as they use to be.

I have been told that our heat is the reason for so many scopes being returned to Leupold etc as compared to other countries.

Mike

quote:

Originally posted by 500N:
makeminestainless

I have hunted here in Australia regularly over 100c and even up around 110+

Never had a problem although I am conscious of
possible issues MAY arise so keep my eyes and ears open.

One thing I did find is that the ammo (and guns) do get damn hot, even in just your ammo belt.

Ummm. No, No you haven't

100F maybe

ever been to ATL?
same thing.
same smell.
more concrete.

I shoot here in the Arizona desert frequently... I've been at the range when it was 115 + and even my Weatherby showed no pressure signs... That was with factory ammo which is loaded pretty hot... If you're hand loading to borderline pressures at 90F then 100 + might end up a bit of an issue if things aren't kept out of direct sunlight...

Just my 2 cents...

Ken....

My other 2cents worth. The only factory .458 Win ammo that I have ever seen jamb up an action was some 350grn A square "practice" ammo and Hornady's "Heavy magnum" Both times were in the Zambezi Valley- once at the rifa training course and once on the proficiency exam itself. In both cases the rifles and ammo were hot before the shooting started and the rifles jambed around rounds 8-10. With the Hornady ammo we were able to duplicate the problem in two other rifles, but that A square round was just a funny. All the rest were quite low pressure

What is "Africa hot"?

Bakersfield, CA. Thursday it was 108 at the airport and 113 downtown.

Arizona, So. Calif., Texas is as hot as anywhere in Africa, if you don't think so take a trip to Blythe Cal. or Presidio Texas this week...

Anywhere you leave a box of ammo on a truck hood in the summer is apt to cause you problems...and if you overload ammo it will perform hotter than it did last winter and just might pop your cork..

Most problems with guns and ammo are caused by the last nut in the buttstock, the one that pulls the trigger.

Amen to that Ray, a couple weeks ago my buddy was passing thru Needles,CA at night and it was still 115 degrees!

The Arizona deserts hitting 120 isn't too unusual. It's like opening the oven with your face next to the door.

It was 129 degrees Friday in Death Valley and 121 in Baker California.

Well I am glad it never gets "Africa hot" hear in Texas. Yuall come down and we can walk up some pigs this August. Actually we are having a very wet and cool year. I think if you take normal precautions such as don’t start with the top load and work up, don’t leave your ammo in the sun all day on the dash of the truck, I think you will be fine. Drink lots of water.
Bill

quote:

Originally posted by GeorgeS:
It's not really the ambient air temperature that will make big a difference in your loads; it's how hot the chamber and ammunition get.
George

George is dead nuts on here......I wouldn't give a damn how hot the weather got.....just don't leave the ammo in the sun on the dash of the auto where it can get so hot you can't touch it to pick it up!

Prairie dog shooting in 100+ degrees taught me that the (as George says) ambient temp means nothing.....it's how hot the ammo gets.....