H4895 temp sensitivity

The temperature data that Hodgdon shows have been verified by A Canadian gun nutz moderator, Kombayotch, [I think designing strain gauges is his day job].

He took a heater and an ice chest to the range and measure with a thermometer and a chronograph.


I think he also verified the testing of Copper solvents [KG12 by a mile].

Since then IMR has come out with two powder that are temp stable and anti Copper fouling.
 
I have used H4895 in several cartridges and the only time I had an issue with temperature was when shooting prairie dogs with the 22/250rem. I had them loaded at the top end and they were fine when it was 65-70 degrees out but when the temp soared to 100+ I had a protruding primer and then a blown primer on the next round. I backed the charge off .4 grain and didn't see any signs of excessive pressure, but I don't think I have shot it in that kind of heat again. I don't believe this load would blow primers in high temps.
 
h4895 is cartridge, primer, and pressure dependent like the other extreme powders... I've had very good uniformity with it in my 5.56 tossing 75 grain pills full throttle, with little difference at all between temp extremes. I have had some trouble with it in my 25wssm with mild charges pushing 100 grain pills though. It was at 3050 fps in cold weather and 3150 fps in hot weather with the same ammo lot.
I possibly could have tightened the spread on the wssm with a primer switch, but the rifle only shot well with a mild load so I was a bit hamstrung.
 
I know this thread is years old. I cannot find the listed PDF. DTIC has changed its web interface. Can this document be posted for retrieval? If so, thank you.

Update: Dredging through the Defense Technical Information Center for days, is this the document title: "The Sensitivity of Double Base Propellant Burning Rate to Initial Temperature" (https://apps.dtic.mil/sti/tr/pdf/ADA022200.pdf)
 
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According to the temp sensitivity charts, H4895 only varies by .23 fps per degree F.

Its not completely insensitive
but many ball powders are 1.0 or over.

Its a pretty insensitive
 

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