Question about reloading when it's cold

Maddog 521

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I'm reloading in my cold garage that is about 45 degrees. Will there be any noticeable difference when I shoot these at say, 80 to 90 degrees? I don't usually load at these temperatures but we got that cold blast and I need to get this done. I'm loading .45acp and 9mm. Thanks
 
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I went shooting on Sunday. And a couple of my hard cast 45 acp loads hung up going into battery. It was only 25 f. I also noticed that the poi on one of my 40 s&w loads was lower than usual. These were well developed loads but never fired them when it was that cold before.
 
Depends on when you work the loads up. If you worked the loads up in summer, loading them in winter has no affect, with most powders. Some powders are inv temp sensitive, so if you worked up a max load in summer, could blow a primer in winter & vise versa with other powders. If you are loading target ammo, well off max, then it's not going to matter much either way.
 
For sporty winter shooting, find some surplus WW II Russian ammo. The stuff is loaded to give full performance at -40° F.

A heater to keep you warm is a good idea, but it won't affect the ammo.
 
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I went shooting on Sunday. And a couple of my hard cast 45 acp loads hung up going into battery. It was only 25 f. I also noticed that the poi on one of my 40 s&w loads was lower than usual. These were well developed loads but never fired them when it was that cold before.

Could also be the gun, depending on how/what you lube it with. Loads that barely function in summer will likely fail below zero. The exception is powders that are inv temp sensitive as noted in the previous post. WST is one, there are others. Put together a good midrange loads, it will run from zero-120 deg w/o fail.
 
Could also be the gun, depending on how/what you lube it with. Loads that barely function in summer will likely fail below zero. The exception is powders that are inv temp sensitive as noted in the previous post. WST is one, there are others. Put together a good midrange loads, it will run from zero-120 deg w/o fail.

Yeah I kinda figured it was the whole package. We rarely get weather that cold here. I don't think I have ever seen cold weather lube here now that I think about it. I just had my normal rem oil regimen. I think the differences in brass, lead, steel, and wood with how much they constrict in the cold could be part of it too. The speer lead bullets are tumble lube type to and there might be something to that. The difference wasn't terrible but certainly noticeable. Kinda interesting to see how they perform at this temperature. Noted!
 
I'm loading .45acp
5.6 gr. W231
230 gr. Precision Delta FMJ
Mixed cased with Tula primers.
I've loaded this load before and it works pretty well in my 1911's and a S&W CS45. It seems that I recall reading that temperature change's might/will affect the end result. I should of mentioned the load data in the first post. Thanks
 
I'm loading .45acp
5.6 gr. W231
230 gr. Precision Delta FMJ
Mixed cased with Tula primers.
I've loaded this load before and it works pretty well in my 1911's and a S&W CS45. It seems that I recall reading that temperature change's might/will affect the end result. I should of mentioned the load data in the first post. Thanks
Depending on your oal, that load is well into max. If you dev that on a cold day, could push into an over pressure Event.
 
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If I understand it correctly, the OP wanted to know about the effects of loading ammo in the "cold" (45 degrees is not cold enough to make any difference), not the effects of cold temperature on ammo that was developed in warm weather. I can't see how there would be any ill effects from using proven data and loading ammo to that data while in a 45 degree environment.

I can say with experience that years ago I loaded a huge amount of 223 ammo, and then went prairie dog shooting, where the temperatures were in the low hundreds. I got blown primers on almost every shot. I had to switch to my 22LR back-up rifle. Lesson learned was high temperature can dramatically raise pressure.

I have never had any trouble in low temperatures, although I hear that ball powders can be difficult to ignite at below 0 temps.
 
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I'm loading .45acp
5.6 gr. W231
230 gr. Precision Delta FMJ
Mixed cased with Tula primers.
I've loaded this load before and it works pretty well in my 1911's and a S&W CS45. It seems that I recall reading that temperature change's might/will affect the end result. I should of mentioned the load data in the first post. Thanks

The velocity of a load will vary somewhat depending on the
temperature of the ammo when it's fired. Temperature
variations during the loading process will have no effect on
the ammo. The warning is directed at those who work up
maximum hand loads that are tested and found safe in cold
weather and then find they are over pressure when fired in
hot weather. This is more common to hunters who will work
up loads in centerfire rifles that are at absolute maximum
pressure for the rifle in cold weather and then later in the
year decide to shoot a few at summer temperatures.
 
Maddog 521, I don't think the temp you are reloading at makes much of a difference in how the cartridges will perform. I rather loading in my garage when the temp is in the 40's to 50's personally as then I'm not sweating my butt off like in the middle of summer. The only thing you might have to watch out for is static electricity buildup in the colder, drier air. I live in southern Louisiana and we usually don't have cold dry days here either. I did load quite a bit of ammo last winter and I didn't see any performance difference between that ammo and ones loaded on hotter, moister days.
 
magnum primers with 296/h-110 and it won't matter the temp. I have shot 357 and 44mag loads at 0 degrees and colder and they went boom every time.
 
Red Dot, Blue Dot and Green Dot are all very temperature sensitive! Hodgdon "Extreme" powders are suppose to be LESS sensitive, but +100 degree temps will affect loads developed below 65 degrees, and vise versa. But 5 grains of 231 always burns the same at 70 degrees weather loaded at 45 or 95 degrees, same for all dry propellants. (The military liquid artillery propellants are a little bit different! I think weight remains the same but the volume is adjusted.) When I developed my 223 Remington load back in the mid 80's, I used small rifle mag primers in hot weather. The longer duration 'flash' helps with cold weather ignition, but the load is still in safe pressures in hot temperatures. I've fired them on 105 degree days with the ammo laying in the sun without any primer cratering. On the other hand my recently developed 338 Lapua Mag load was around Max at 65-70 degrees (and it shot very well at 20 degrees), but on a 95 degree day the cases seized to the chamber! That is a Hodgdon US 869 load with a 300 grain bullet. I need to make a Retumbo or H 1000 load OR stick with the less desirable 250 grain bullet for summer use. One of my friends, loads high pressure Bench Rest loads, based on barometric pressure, not temperature. Shooting at 800' in Ohio is a lot different than 7000' in Montana! Ivan
 
I'm loading .45acp
5.6 gr. W231
230 gr. Precision Delta FMJ
Mixed cased with Tula primers.
I've loaded this load before and it works pretty well in my 1911's and a S&W CS45. It seems that I recall reading that temperature change's might/will affect the end result. I should of mentioned the load data in the first post. Thanks

I have used that powder charge with a 230 gr bullet in extreme temperatures with no problems. It was my standard match load for combat matches.

As always, it is best to try it under the circumstances you will be using it in your own pistol.
 
Thanks for all the comments. Looks like I'm good to go. Sure hope it warms up soon.
 
I never thought much about low temps being a problem as we don't get really cold, at least not usually, this week being an exception. Glad you posted this, I am planning on loading some 45 acp tomorrow so I will pay closer attention to how everything works. Where are you located? I think we are supposed to be in the 50s tomorrow.
 
Rifle or pistol loads will shoot differently depending on the temperature. Loads developed during summer will in the dead of winter hit lower and vice a versa. I've seen it on rifle ranges. And once when I left my match ammunition at home, I had to deal with it when I had to use my practice ammunition for a vintage military rifle match. The difference in average temperature was just about 65 degrees colder. Point of impact was notably lower and because I'd loaded the practice ammunition very light, in the below 30 degree weather that prevailed at that match the bullets were loosing stability as velocity dropped below sonic... probably no more than 1,000 fts. Shot excellent scores, but some of the bullets hit the target slightly sideways. Had those loads been developed for such cold weather it is doubtless that in the heat of summer the loads would have been snappy.
 
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