2206h temperature sensitive?

[scott/r]

Just wandering if 2206h is temperature sensitive enough to warrant dropping a couple of 10th of a grain out of a load that was developed in may, when it was a fare bit cooler than it is now?

[plumbs7]

Just wandering if 2206h is temperature sensitive enough to warrant dropping a couple of 10th of a grain out of a load that was developed in may, when it was a fare bit cooler than it is now?

Hi Scott, I see nobody has answered ur post ! So I thought I would say Ga day and have a crack at it!
In my experience with 2208 between summer and winter it does make a difference of about 20-30 or more fps. Between summer and winter . My pet load with 155 hybreds is 46.5 2208 Palma brass at around 3040 fps in summer ! This drops to about 3000 fps in winter . I know at the Nats the speed was down a lot even to 2980 ( winter) and was out of the node. I left the bullets in the sun and had a good 1000 yds range !
In my opinion testing ur velocity is very important , especially when u seat ur pill a few thou deeper. As albittle more space in the cartridge = less pressure which = more powder( but not always ).
Maybe best to tune ur load in summer and retune in winter with a magspead and try and stick with the velocity that ur rifle likes.

2209 seems a lot more stable with temp since I've been moonlighting in open!
Ps I hate NorthArm! Lol
Pss I have no experiance in comps with 2206h so I can't comment on that as such!

[saum2]

Scott,
Yes I believe 2206H is temp sensitive. No proof with speeds etc, but I'm sure when I shot TR last with 2206H it was great during winter but in summer the groups fell away using the same powder charge, so probably just enough to go out of the good node. So maybe .2-.3 less during summer may be the go.
Geoff

[Brad Y]

All powder is temp sensitive. Some more so than others. You need to do the testing to know where you need to be to stay in tune.

[scott/r]

Thanks guys for your replies. I got to do some rushed tests in between the rain last weekend. The heat has definitely made a difference of about 40 - 45 fps. I've dropped .2 grn to get back to just over 3000 fps which the old girl seems to be happiest.

[johnk]

Remember there are two definitions of temperature sensitive:

The difference that occurs when a load held at a controlled temperature is shot at different ambient temperatures.

The difference that occurs when you shoot loads that have been festering in a car boot at 60degrees compared to one held in benign storage.