Powder Test 7mm Rem Mag

I was under the impression as a New reloader that H4350 & IMR 4350 were different ? I thought the IMR was a little more temp sensitive ? Is this not correct ? And is there a big difference from older IMR 4350 as to the newer lots ? I have a few pounds of each but have yet to test any of it.
H4350 is probably one of the most stable I've seen. It's more stable than H4831 and h1000
 
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The difference in velocity between the three 4350 powders has a lot to do with the cartridge case capacity fill and the bullet weight.The three powders are different in weight volume per grain of powder.The A4350 is the lightest and takes up more case space,followed by IMR4350.It falls about right inbetween A4350 and the heaviest H4350.Here are some examples of what I have loading all three the same.
308 Norma Magnum 168gr Nosler Ballistic Tip
H4350 69.0grs 3148fps
IMR4350 69.0grs 3111fps
A4350 69.0grs 3125fps (70.0grs 3168fps)

308 Norma Magnum 180gr Nosler Ballistic Tip
H4350 69.0grs 3028fps
IMR4350 69.0grs 3103fps
A4350 69.0grs 3065fps
I ran this test years ago in my 30-06 A4350 was the fastest,followed by IMR4350,about 10fps slower,followed by H4350 being the slowest by about 25fps slower than the fastest.All the powders grouped about the same.
What is your 308 Norma Mag setup? Mostly concerned if you have the old style long freebore or the more recent SAAMI spec freebore?
 
My Rem 700 loves R#22, CCI 250, Rem brass, 140g Nosler ballistic tip, accubond, or partition at 68g. Work up to this load as various lot# of R#22 vary a lot. 67g of R#19 in a Win Case with Fed 215 for Barnes 140t TTSX with a .050 jump is extremely accurate. Bullets are all touching with both of these loads, 7 Rem Mag, Rem 700, and Brownings.

I barely touch the lands with the Noslers, Keys to the Kingdom like in this tid bit, 140g Nosler ballistic tips are just unbelievably accurate and they are tougher than the 140g Berger VLD hunting at this velocity....in Spades.
 
My Rem 700 loves R#22, CCI 250, Rem brass, 140g Nosler ballistic tip, accubond, or partition at 68g. Work up to this load as various lot# of R#22 vary a lot. 67g of R#19 in a Win Case with Fed 215 for Barnes 140t TTSX with a .050 jump is extremely accurate. Bullets are all touching with both of these loads, 7 Rem Mag, Rem 700, and Brownings.

I barely touch the lands with the Noslers, Keys to the Kingdom like in this tid bit, 140g Nosler ballistic tips are just unbelievably accurate and they are tougher than the 140g Berger VLD hunting at this velocity....in Spades.
I loaded some from 66 to 68 grains but have not tested them yet. Next month I will
 
Calvin, I am laying in a supply of H, and have about three pounds left of the IMR which will go by the way of the DOO DOO bird at my house. We freeze to death at 32* here, and our deer hunting is usually in 45-65*F, where I work up loads in 70-75* in a heated/cooled shooting house, thus using powders like R#22 is of little consequence. I have heard rumors of R#23, never actually seen any in person.
I had a pound of rl23 in my stash some time ago…I sold it because I figured I'd never see it again and didn't wanna end up falling in love with an unobtainable powder! 🤣

I do shoot and hunt with some temp sensitive powders, it's not the end of the world, just gotta make sure it's safe when it's hot out…no hot rodding loads in in January and then taking them for a rip in July haha. Of course, the desire to go shooting and do load development gets less and less in the december-February deep freeze the older i get. Can't tell if I'm getting wiser or just weaker haha. Not that I'm old, but the 20 year old version of me was just about impervious to cold. I'd go shooting in -20 to -30 weather on a regular basis and think nothing of it, froze my hand pretty good a few times after getting fed up with trying to shoot with gloves on and just doing it bare handed and gritting my teeth after having them exposed for half and hour. Younger, tougher, and more stupid haha.

But this really would be a great place to test temp sensitivity if I had the time and desire to do so. I know many places get hotter than us in the summer and some places get colder in the winter still, but I honestly don't know anywhere on earth that gets as hot AND cold and has more difference between seasons. Some places are about the same, don't think anywhere is more tho.

Hottest I've seen in person living where I do (not including humidity or windchill factors in these numbers, just actual thermometer readings) is 41 celcius or so, about 105 Fahrenheit. Coldest I've seen on a thermometer with my own eyes is -54 celcius or about -65 farenheit (I was in high school then, I recall how the news headline was "today Saskatchewan is colder than Mars" haha). Again, I don't think anywhere that gets appreciably hotter than that gets anywhere close to that cold in winter, and vice versa. That's a 95 degree celcius extreme swing possibility over 6 months, basically the same difference that separates ice from boiling water.

Let the record reflect, if I have to choose I'll actually take -40 over +40 (Celsius) every time, no question. You can dress for the cold and be fine. But that kind of obscene heat IS FOR REPTILES ONLY! I AM NOT A LIZARD!!!!🤣🤣🤣
 
Calvin, I am laying in a supply of H, and have about three pounds left of the IMR which will go by the way of the DOO DOO bird at my house. We freeze to death at 32* here, and our deer hunting is usually in 45-65*F, where I work up loads in 70-75* in a heated/cooled shooting house, thus using powders like R#22 is of little consequence. I have heard rumors of R#23, never actually seen any in person.
I really like the imr4350 even with huge temp swings, however I usually never shoot when it's over 80*.
 
I had a pound of rl23 in my stash some time ago…I sold it because I figured I'd never see it again and didn't wanna end up falling in love with an unobtainable powder! 🤣

I do shoot and hunt with some temp sensitive powders, it's not the end of the world, just gotta make sure it's safe when it's hot out…no hot rodding loads in in January and then taking them for a rip in July haha. Of course, the desire to go shooting and do load development gets less and less in the december-February deep freeze the older i get. Can't tell if I'm getting wiser or just weaker haha. Not that I'm old, but the 20 year old version of me was just about impervious to cold. I'd go shooting in -20 to -30 weather on a regular basis and think nothing of it, froze my hand pretty good a few times after getting fed up with trying to shoot with gloves on and just doing it bare handed and gritting my teeth after having them exposed for half and hour. Younger, tougher, and more stupid haha.

But this really would be a great place to test temp sensitivity if I had the time and desire to do so. I know many places get hotter than us in the summer and some places get colder in the winter still, but I honestly don't know anywhere on earth that gets as hot AND cold and has more difference between seasons. Some places are about the same, don't think anywhere is more tho.

Hottest I've seen in person living where I do (not including humidity or windchill factors in these numbers, just actual thermometer readings) is 41 celcius or so, about 105 Fahrenheit. Coldest I've seen on a thermometer with my own eyes is -54 celcius or about -65 farenheit (I was in high school then, I recall how the news headline was "today Saskatchewan is colder than Mars" haha). Again, I don't think anywhere that gets appreciably hotter than that gets anywhere close to that cold in winter, and vice versa. That's a 95 degree celcius extreme swing possibility over 6 months, basically the same difference that separates ice from boiling water.

Let the record reflect, if I have to choose I'll actually take -40 over +40 (Celsius) every time, no question. You can dress for the cold and be fine. But that kind of obscene heat IS FOR REPTILES ONLY! I AM NOT A LIZARD!!!!🤣🤣🤣
I can't remember the exact year but I think it was 2001-2002, we went from 63*f to-26f in a 36 hour period, to the east of us got to-32f that night, not a whisp of wind, when the sun went over the horizon it was like something was sucking any warmth out of the air, never experienced anything quiet like it.
Summer temperatures are usually 105-115f during the peak and winter down to 0-40
 
I can't remember the exact year but I think it was 2001-2002, we went from 63*f to-26f in a 36 hour period, to the east of us got to-32f that night, not a whisp of wind, when the sun went over the horizon it was like something was sucking any warmth out of the air, never experienced anything quiet like it.
Summer temperatures are usually 105-115f during the peak and winter down to 0-40
The funny thing is, here when it gets down to that -40 range (Fahrenheit and celcius meet there) if you dress appropriately for that you'll be fine, and it's a very dry cold, the air is absolutely bone dry when it's that cold - hard on the lungs it's so dry, even with snow everywhere.

The coldest I've felt I think has been much "warmer" - barely below freezing, and WET. once on the west coast, Vancouver, in February. I was on the shore of the Pacific Ocean and when the sun went down over the horizon the absolute wall of cold air coming off the ocean that hit me was inescapable. You couldn't get away from it. It got right into your bones. I felt embarrassed being a prairie boy accustomed to much lower temperatures and not feeling cold in them…I was shivering uncontrollably, teeth chattering. It was right around 0 celcius or 32 Fahrenheit.

The other time was more recently here in Saskatchewan. Ironically it was during a bout of very unseasonable warmth for January. It was only -10 celcius or 14 Fahrenheit….but apparently it was much warmer higher up because it was RAINING! The raindrops were so supercooled they were instantly forming ice on hitting the ground, no puddles. Scariest roads ever, absolute skating rink. But I didn't know it could rain liquid water that far below freezing. And it's friggin COLD getting rained on in January in Saskatchewan haha, way colder than -30 and snowing.
 
It was like that that night, dry super cold and burned your lungs and nose to breathe.
Usually it's a brutal wet cold with howling winds, cuts you to the bone even with lots of cold weather gear on
That checks out. Between that dry cold and natural gas furnaces further drying the air out I get nosebleeds all the time from November to March. I've never got one in the summer.

Your neck of the woods, and Colorado, take the cake for how rapidly the weather can change in 24 hours like that, along with the chinooks in Montana/Alberta. We have huge seasonal differences but in each season get pretty "locked in". In June and July it just doesn't cool down as a rule, even at night. And most years, with some exceptions, the last half of December to the end of
February is truly unrelenting cold.
 
The funny thing is, here when it gets down to that -40 range (Fahrenheit and celcius meet there) if you dress appropriately for that you'll be fine, and it's a very dry cold, the air is absolutely bone dry when it's that cold - hard on the lungs it's so dry, even with snow everywhere.

The coldest I've felt I think has been much "warmer" - barely below freezing, and WET. once on the west coast, Vancouver, in February. I was on the shore of the Pacific Ocean and when the sun went down over the horizon the absolute wall of cold air coming off the ocean that hit me was inescapable. You couldn't get away from it. It got right into your bones. I felt embarrassed being a prairie boy accustomed to much lower temperatures and not feeling cold in them…I was shivering uncontrollably, teeth chattering. It was right around 0 celcius or 32 Fahrenheit.

The other time was more recently here in Saskatchewan. Ironically it was during a bout of very unseasonable warmth for January. It was only -10 celcius or 14 Fahrenheit….but apparently it was much warmer higher up because it was RAINING! The raindrops were so supercooled they were instantly forming ice on hitting the ground, no puddles. Scariest roads ever, absolute skating rink. But I didn't know it could rain liquid water that far below freezing. And it's friggin COLD getting rained on in January in Saskatchewan haha, way colder than -30 and snowing.
I have worked in three deserts, NW Siberia, Williston North Dakota. I have seen mothers pushing strollers with babies in -45C and worked on a rig floor with -65F until the hydraulics froze. 5 minutes on 10 minutes in the dog house on that job. Extremes are extremes, but I understand, there is only so much you can take off in The heat.
I don't go shoot in 90F, I do my load development under 80F and hunt between 20-70F. I always confirm my loads before a hunt but it's always warmer then when I shoot at the game. Never had issues. Been lucky.
 

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