Blue Dot and Cold Weather

[Andy_P]

I like Blue Dot in my 44 Mag, and I'm about to do my own cold weather tests, but have found opinions on both ends of the spectrum.

Poor Cold Weather Performance - all seems to go back to a single source: "The only specific reference to cold weather powder behavioral changes that I recall reading were by the late Bob Milek in the 1970's. This concerned the 357 Magnum and the then-new Blue Dot powder. Mr. Milek reported that at temps in the range of -35* F, Blue Dot occasionally produced unpredictable/random pressure spike indications." I have not been able to find any other first-hand accounts, much less reliable, verifiable accounts.

Excellent Cold Weather Performance - Claimed by a number of sources to the extent that it is actually recommended. Numerous sources based on personal experience. Granted claimed, but not verified.

We all know how gun "folklore" is born and grows - a single statement, accepted without question, that then grows in scope to become a dogma of the gun religion. Is this folklore or is there something to it?

[45 2.1]

Back in the 70s, I shot the 38 Super in the Colt 1911 a lot. A friend had shot the Super for a couple of years with BlueDot with high velocities and very good results. He didn't get out for long in freezing weather though. I do, and shot the BlueDot loads quite a bit in above freezing weather. One very cold day I had been out for an hour or so and the gun was in an exposed holster and was "COLD", way below freezing in temperature. The first shot was very hot, much hotter than usual, the second blew the case web and cracked a grip panel. Over the next couple of months (in freezing weather) I reproduced the effect. Get that BlueDot load to freezing temperature and you could blow a case, shoot the same ammo with the ammo above freezing temperature and everything was OK. Bluedot was abandoned by me thereafter. Nope the gun wasn't hurt (just lost the grip panel and had to squeeze the mag back to thickness), but the pressure was very high at freezing temperature and normal at 40 degrees.

[44man]

I can't answer that but I do have a lot of shotgun loading info that says "not a cold weather load" using Blue dot and other powders.
Never gets real cold here in eastern WV anyway.

[C A Plater]

I've seen that in print about Blue Dot and shotgun loads and report similar effects with Red Dot but not as pronounced. The "cure" for shot shell loads was said to be compressed charges, hotter primers and heavier lead shot loads.

There is this link with details: http://www.ballisticproducts.com/bpi/articleindex/articles/curmudgeon_articles/060329_hotcoldpowder.htm

[doghawg]

My favorite .41 Mag "woods bumming" load is a 215 cast over 10.5 gr. of Blue Dot and sparked by a Win LP. That loads averages at 1080 fps from a 4 5/8" BH in warm weather. Last summer I put some loads in the freezer for a few hours and then packed them in ice in a cooler and headed to the range. Average velocity was up to 1145 fps.

Blue Dot is still one of my favorite powders but I don't use it for max loads.

In contrast to the above, I chilled some .44 Mags with 21 gr. of 296 under a 300 gr. GC and those loads chronyed 50 fps slower.

Randy

[Andy_P]

Interesting. I went out today and shot 30 rounds of 44 mag (240gr Lyman over 15.0 grs of Bluedot) and hit most of the Clay Pigeons I shot at. Ammo, gun and I were a few degrees below freezing - no chrony to gauge it, but none of the shots were obviously "over pressure".

This is not settled for me. It would take a controlled experiment to convinve me, but even if Bluedot was shown to gain pressure with lowering of temperature (counter-intuitive isn't it?) then, the question would remain: "What about other powders?"

[georgeld]

WOW!!

Never dreamed being real cold would make it become a hotter loading.

I've used Red Dot in .38's for yrs, carry them on a pistol belt and gun while elk hunting. Shoot some now and then just for the hell of it to hear the noise at times while up there. Gets plumb nasty cold at times and never noticed anything different in the way they pop.

Mostly just a plinker load though. 4gr under 147gr SWC and CCI primers.

[Ricochet]

In George Frost's book "Ammunition Making" (an excellent book which I recommend for every handloader's library) he mentions that some early Winchester-Western Ball powder loaded rifle cartridges had excessive pressures when exposed to extremely cold temperatures due to the nitroglycerine in the powder freezing and fracturing the powder grains, causing faster burning. He said (I'm going by memory, I don't have the book with me) that they reduced the nitroglycerine content to cure the problem, and began routinely testing ammo at -40 degrees. (Supposedly the same Fahrenheit or Celsius, I haven't checked it.)

That makes me wonder if other powders with a high percentage of nitroglycerine are at risk for the same effect.

I believe he also said that 295P was the Ball powder they used in loading .44 Magnums until they got field reports of squibbing in very cold temperatures, solved by switching to the slightly faster burning 296.

[felix]

Ricochet, I think you hit the nail on the head about the dibutyl phthalates being used as the principle plasticizer, as well as a deterrent, in at least some of the powder formulations. That chemical seems to keep the nitroglycerin in check when the weather is cold, like it does for fingernail polish. Wimmin bitch and moan about their nails "cracking" with a hard formulation polish (extreme shine) not having this chemical as a constituent. ... felix

[Four Fingers of Death]

Check wiith Hodgsons clays, clays international, etc, they are aussie made powders made by the factory that make the powder for our military(ADI brand). All powders they make are not effected by ambient temprature. I tested the AR2206 (around 3031, 2064) in a 308 Mauser in the late 80s, I left some in the sun, (it was a stinker that day), some in my ammo box in the shade and some in a plastic bag in the ice box, covered in ice. For the sun warmed (almost too hot to handle), I donned safety glasses and a full face grinder mask, which made it difficult to shoot properly (didn't think of that before the test). The normal and cold ones were normal sized groups for the rifle, about 1 1/4" and the hot ones were bigger, but I couldn't get a good position for my head with the mask. But the group centre line was right in line with the rest and extraction effort was similar and the primers were similar. Not actually scientific methodology, but better than nothing. I now have a Caldwell lead sled, I must try it again as I could get a consistent hold on the rifle with it.