IMR powder vs Hodgdon powder on temperature sensitivities

[Horsethief]

Confirm this if you can: IMR powders are temperature sensitive. I'm looking for specific references OR experienes with IMR-4831 and IMR-4895 in temperatures under 32 degrees F. I know the powders by Hodgdon, such as H-1000, 4831, 4350, are not sensitive.

 

[Ridge_Runner]

all powders are somewhat temp sensative (yes even the extreme hodgdon powders) but single based powders are not nearly as sensative as ball or double based powders due to the addition of nitroglycerine in they're make-up, how sensative they are depends on the amout of nitroglycerine they contain.
RR

 

[Polaris]

Have not yet tried Hodgedon "extreme" series powders, but I have fired a lot of Viht. N140 touted to have the same temp insensitivity. I also have a lot of experience firing OTM tactical, match and hunting loads with IMR 4320 and IMR 4350 in .308 win, 280 rem, 7,5X55 swiss and 7,62X54r at temps from 95F to -15F.

I think unless you are a benchrest or 1000 yard shooter where tiny fractions of a MOA will separate the wheat from the chaff, you can look at this feature as more of a selling point than something for the rest of your loading choices to orbit around.

Have not run any comparisons on the chronograph at different temps but I have compared groups hot vs cold weather, hot vs cold barrel, hot vs cold cartridges and most combinations thereof and found the differences to be negligeble. I have gotten significant POI shifts given extreme temperature swings, as well as noticed pressure spikes with very hot loads worked up in cooler weather especially with IMR 4350 in the .280 rem. These seemed less pronounced in the shorter military cartridges. I also got POI shifts with VN140 in the 308 win with extreme temp changes.

I would test a few powders suitable for the load you want to work up and select the best regardless of whether it's an "extreme" powder or not. I have not found any of the IMR types to give truly inconsistent results in extreme cold given quality components, primers and procedure. Have only encountered incosistent cold weather results with Spherical powders BL-C2 and H380.

Perhaps somebody with more time on their hands has done chrono testing on this subject, but again, for practical purposes I feel little need to switch from standard IMR types I am using.

 

[clearwater]

It seems related to each rifle, like most things in reloading. For me imr powders usually give better
MOA results, so at what point do temperature fluctuations overcome repeatable precision. A hunter in
Montana whith 100 degree swings in temperature during a hunting season may need the Hodgdon
powder more than hunters from other parts of the country.

 

[Guy Miner]

"A hunter in Montana whith 100 degree swings in temperature during a hunting season may need the Hodgdon powder more than hunters from other parts of the country."

Yup. I tend to use a lot of Hodgdon "extreme" powders. Am bear hunting in 90 - 100+ degree temps. Will be coyote hunting in 15 - 20 degree temps this winter. Target shoot all year round, particularly with the .308 Win.

I've seen temp associated problems mostly at the target range on the 500 & 600 yard ranges. Rarely do I shoot farther than 600 yards.

I have had VV loads that were perfectly fine at 60 degrees become WAY too hot at 85 degrees. Threw out a bunch of once-fired Lapua .308 brass when the primer pockets were enlarged too much. I don't know the velocity of those loads. They shot great, but required a fair bit less elevation dialed in at 600 yards.

Switched back to Hodgdon's Varget and have never had a problem, at zero degrees (literally) or at 100+ degrees. A couple of clicks of elevation on the scope one way or the other and all was well. No pressure problems like messed up brass or stiff bolts. It's worth noting that velocity, and pressure, can vary a fair bit, depending on temperature.

Also had some FACTORY Winchester .308 Win match loads that warmed up at the range and literally locked up the bolt on my FACTORY Rem 700 VS. That was interesting, and it was years before I finally finished off that box of ammo in cool temps. Heck, I might still have a few of those left... They were HOT in warm temps, no doubt.

Have been using more RL-15 in recent years, and read somewhere that it's been treated to be less temperature sensitive. It sure seems to work well, though I haven't used it in the extremes I've used Varget.

My apologies about all the .308 references. I likely shoot about 10 times the amount of .308 ammo as I do any other center fire cartridge - hence most of my experience is with that cartridge, particularly at long range.

Yes, I'm a fan of powders that are less temperature sensitive.

Regards, Guy

 

[bullet]

I have used a lot of IMR, Alliant and Hogdon powders and in 2003 Hogdon powders purchased IMR powder line. In my use of IMR, Hogdon extreme and Alliant for years I have had outstanding consistency in using IMR powders and from very hot conditions in Africa close to the equator and in almost zero weather in parts of the US I have found IMR expecailly IMR4350 and IMR7828 to be much less senitive to tempatures than is claimed on the internet discussions and rehearsed on forums. In constant work at the reloading bench in the dead of winter to the very hot and humid summer time, I have found very little change in velocities, extreme spread, divation or group size once I had finalized a hunting load. I have had much better consistency out of IMR7828, IMR4350 than Alliant RL-22 or Alliant RL-25 and not enough difference between Hogdon H1000 or H4350 and IMR7828 or IMR4350 to even debate.

When I go to my different hunts because of temp and humidity along with altitude I always fire a five shot group over a chronograph so as to sight-in properly and adjust my sight in. In doing so with my other magnums like my 7mmSTW, 300Win mag, 300WBY and my 340Wby, I use some of these same powders. What surprised me is that in cooler weather my groups tighten up and sometimes I loose a little velocity (with RL-22, RL-25, much more velocity loss and changes in group sizes, but H1000, H4350, IMR7828 and IMR4350 very close in velocity loss and not much at that) and at altitude of 3,500ft or above I have not experience any significant lose of velocities with IMR or Hogdon powders that I have used, but still experience tighter groups.

I have found extremely good Deviation numbers with IMR7828 and IMR4350 and with Hogdon H4350.

 

[usmc 89]

I use the hodgdon extreme powders in all my stuff varget. 4350 4831 h1000 and retumbo covers all of loading. have used re15 in the past and found it a bit irritable when the temp got up over 80 degrees when running it near the tip of suggestion, great powder just went with a less finicky powder. I do have four pounds on N160 laying around I would probably get rid of pretty reasonably if anyone were interested

 

[bullet]

I use the hodgdon extreme powders in all my stuff varget. 4350 4831 h1000 and retumbo covers all of loading. have used re15 in the past and found it a bit irritable when the temp got up over 80 degrees when running it near the tip of suggestion, great powder just went with a less finicky powder. I do have four pounds on N160 laying around I would probably get rid of pretty reasonably if anyone were interested

PM sent

 

[Oldtrader3]

I have typed this response (5) times now and had it eaten each time.

When I hunted high mountains in eastern Washington, Utah and Wyoming back in the old days when they had late elk seasons, until December, I used IMR powder in my rifles with magnum primers substituted for standard primers. This was only during times when temperatures were below 20* F, down to minus zero F. My loads are not really hot to start and I never had any ill effects from this change.

Using temperature stabilized powders does not make any difference in the changes of chamber pressure which are attributed to the Universal gas laws (PV=nRT: Avogadro's formula) and the integrals thereof. That portion of resultant temperature and gas pressure is a function of the absolute temperature rise and pressure increase. The type of powder is immaterial, assuming that the powder calorie content generation (and burn rate) is similar.

 

[Wincheringen]

I have literally hunted in an 80 degree temp swing in two days (+60F to -20F) and never noticed a single problem. Issues typically arise when you're already at the white knuckle edge. I stay away from that and hence have few problems.

Hodgdon didn't purchase IMR, they bought the name and package the product. IMR/DuPont has always made powder for Hodgdon.

 

[bullet]

I have literally hunted in an 80 degree temp swing in two days (+60F to -20F) and never noticed a single problem. Issues typically arise when you're already at the white knuckle edge. I stay away from that and hence have few problems.

Hodgdon didn't purchase IMR, they bought the name and package the product. IMR/DuPont has always made powder for Hodgdon.

Thanks for the clarification on IMR and Hogdon.

Here is a quote from IMR History page on line, so help me understand why is is not a purchase but only buying the name, am I missing something and if so please help me out here.


Hodgdon Powder Company purchased IMR® Powder Company in October 2003. Hodgdon Powder Company offices are located at 6231 Robinson in Overland Park, Kansas. IMR powders continue to be manufactured to the same exacting performance criteria and quality assurance standards that shooters have come to expect.


http://www.imrpowder.com/history.html

 

[Wincheringen]

The only powder that Hodgdon makes is Pyrodex/Triple7/Whitehot. Everything else is made by IMR (General Dynamics/DuPont) (Canada), ADI (Australia), & St Marks (USA). Feel free to call them, they'll tell you that. I already have talked to them. Its the same deal with Winchester powders, they are all made by St. Marks, Hodgdon just packages them. I'm not sure if Olin owns St. Marks or not.

What I'm trying to get at is that the burning of any propellant is just a basic chemical reaction, so technically all gunpowder is going to be somewhat temperature sensitive. Hodgdon calling their products 'Extreme' is just marketing. I can't tell you that it doesn't work, but I tend to avoid things that are extreme.

 

[bullet]

The only powder that Hodgdon makes is Pyrodex/Triple7/Whitehot. Everything else is made by IMR (Canada), ADI (Australia), & St Marks (USA).

What I'm trying to get at is that the burning of any propellant is just a basic chemical reaction, so technically all gunpowder is going to be somewhat temperature sensitive. Hodgdon calling their products 'Extreme' is just marketing. I can't tell you that it doesn't work, but I tend to avoid things that are extreme.

I also assumed as much and your comments helped. As I mentioned in my first post, that I have not had or noticed on the bench in winter or summer any big change in velocities when using IMR or Hodgdon in cold or hot temps and I always use a chronograph in my load work, even when sighting in my load before hunting season.

 

[Wincheringen]

I really haven't tested it that much, I load for over 40 cartridges and just don't have the time or resources to test each and every one to get baseline data. I usually just find what works and stick with that. Currently I'm working on finding a load for everything and simplifying my supplies so I can buy in bulk.

 

[bullet]

I really haven't tested it that much, I load for over 40 cartridges and just don't have the time or resources to test each and every one to get baseline data. I usually just find what works and stick with that. Currently I'm working on finding a load for everything and simplifying my supplies so I can buy in bulk.

Yes, that is the direction that I am moving at this time in my life, because after all these years of load work and testing, both at the bench and final load work for each cartridge in the field on game - I have decide to reduce my work to those specific powders and primers along with brass that worked best for me.

 

[Oldtrader3]

I only load for (7) CF rifles and (6) CF revolvers now but I have developed one load for each caliber and rifle back when I had over (30) long guns and revolvers. Plus, I have standardized on (4) IMR powders and (2) revolver powders in order to make life more simple (KISS!).

 

[nvbroncrider]

I only load for (7) CF rifles and (6) CF revolvers now but I have developed one load for each caliber and rifle back when I had over (30) long guns and revolvers. Plus, I have standardized on (4) IMR powders and (2) revolver powders in order to make life more simple (KISS!).

AMEND!

 

[Polaris]

I only load for (7) CF rifles and (6) CF revolvers now but I have developed one load for each caliber and rifle back when I had over (30) long guns and revolvers. Plus, I have standardized on (4) IMR powders and (2) revolver powders in order to make life more simple (KISS!).

Enquiring minds want to know what your picks are. Think I'll start another thread so I don't hijack this one.

 

[PJGunner]

For more years than I care to count, I've done my load work ups in the summer. When I lived in Nevada that meant tmps in the mid to upper 90s and here in Arizona 100 to 110 degrees. The only good thing about doing it that way was pressure showed up a lot sooner. Come hunting season, if in the southern part of the state temps could run from maybe 65 to 80 degrees and if lucky enough to get a Kaibab tag, temps could run to just below freezing at first light to as high as 75 to 80 degrees by late afternoon, just not necesarily on the same day. Usually before a hunt when I check out my rifle's sighting, I try to do it when the range first opens up while it's still as cool as it's gonna be. I haven't noticed any appreciable change in point of impact even in my 7x57 and .308 Win. loads using W760 which is supposed to be temp sensitive. Maybe it just hasn't gotten cold enough. My .300 Win. Mag. load using Winchester's long discontinued WMR powder did just fine on a very long shot at a cow elk about 8 years agoon a very cool morning. It was a great powder in the .300 Win. mag. and .270 Win. I'll be working with it in my .280 Rem. and we'll see just how well it will do with that cartridge. The only cartridge it has not worked in is the 30-06, yet it's good in the 25-06, .270 Win. and shows promise in the very limited testing I've done in the .280. I just haven't been getting out to shoot lately as for some reason, the heat has been a bother. Never had trouble shooting in the heat before but this year? Damned if I know why. maybe I'm just getting old. :roll:
Paul B.

 

[SJB358]

Never had trouble shooting in the heat before but this year? Damned if I know why. maybe I'm just getting old. :roll:
Paul B.

Paul, don't feel too old buddy. I hate the heat as well and I am half your age. The cool Fall or early in the morning is still favorite time to be out on the range. Heated range days take it right out of me. Brian and I spent the entire Summer last year shooting in 100 degree temps in Va. Never saw a POI change, but man, my enthusiasm sure dropped towards the end of the day!