New temp. stable powder for 6mm CM

Longshot4

New member
I have been collecting my goods for loading my 6mm creedmore. What a pain looking for dependable Load Data. Its been a wile since I had a new cartrage to work with. I was in Cabela's yesterday and found a container of 4166 I thought I would give it a try. Or should I say find load data for it. I found on line some Sierra data but no mention of Primer size (small or large). That's it for IMR 4166.

I have a new box of 95gr. Hornady SST. Cases are Lapua small pockets. Picked up 100 CCI small BR-4 and small 450 Mags.
I Find Data on the net but its bits and pieces. I have a dozen manuals but that's what happens after 40 years. No new ones and the ones I find have nothing for the old guy with an new toy. :confused:

So can any one shine some light on the IMR 4166 powder. The bit on line was with a 95gr bullet so I know I'm almost there.
 

lugerstew

New member
HI, I tried 4166 for a while, in several different loads for my 243win, I was not impressed with the SD and groups of most loads, I only tried one pound and decided to never buy anymore again, I guess my gun just didn't like it, im sure others have different or better results.
 

hounddawg

New member
I suppose you have already found out that Hornady does not list 4166 in thier 6CM load data

https://www.hornady.com/assets/site/hornady/files/load-data/6mm-creedmoor-all-data-v3.pdf

Sierra does for their 95 TMK however

https://sierrabulletsblog.com/2017/10/03/sierra-bullets-6mm6-5-creedmoor-load-data/

and Hogdon also lists IMR 4166 but it is for a Berger 95 VLD. Looks like if you just want to use Hornady data you are out of luck and need to change powder. For what it is worth I use H4350 and 107 SMKs and get .4 groups and am happy with that. Due to the 6.0 CM's comparatively short barrel life you just need to find a bullet and a powder/charge that works and stick with it
 

Marco Califo

New member
IMR 4166 is not a NEW powder. It has been around a few years.
You should look at bullet makers data too. I like the Speer on line load data.
 

std7mag

New member
I'd check with Hodgdon for load data.

And we are still crying "temp stable"??!!
Lot of BS in the real world.
 

Marco Califo

New member
4166 6mm CR data is on IMR's site - link below

I checked Speer & Hodgdon and they do not lost load data for IMR-4166 WITH 6mm CM.
That MAY mean it is not a suitable burnspeed for that chambering. I think the 6mm CM may be newer than the powder. Speer lists MANY Alliant powders for 6mm CM (they have common ownership); more so than other chamberings. I like their format for identifying and comparing powders.
* * *
Hodgdon Reloading data does not list any loads for 4166 and 6mm CM. But, curiously, IMR's product website does: https://imrpowder.com/imr-enduron-4166.
Go to the bottom, select 6mm CR and a bullet weight:

MANUFACTURER
IMRPOWDER
IMR 4166BULLET DIAM.
.243"C.O.L.
2.725"
STARTING LOADS
GRS. VEL.(FT/S) PRESS.
34.9 2,984 49,900 PSI
MAXIMUM LOADS
GRS. VEL.(FT/S) PRESS.
37.9 3196 59,500 PSI
 
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Longshot4

New member
I ended up picking up a Lb. of IMR 4350. Then found Hodgdon Data on line. I have started the break in of the barrel. shoot, clean... I have a box of Nosler 95gr. ballistic tip for hunting if I don't get loads worked up in time. I also have a box of 105 Berger Hybrid Target, and to load 95gr. Nosler Partition and 95gr. Hornady SST to work up loads. Now all I should have to do is take the print out of Hodgdon data and go to town.

Reports to continue


Thanks for your input :)
 
Marco Califo,

Go to Hodgdon's reloading data page. Enter Rifle. Select 6 mm Creedmoor. Then go to the powders and scroll down to 4166, select that and click the button to get data. They've got it for every bullet weight they list.
 

Rimfire5

New member
A lot of the manuals are very slow getting new powder data into their manuals.
That is why I have been using QuickLOAD software for the last 5 years and have had great results with it using newer powders and newer bullets. It sure beats waiting for new manuals to come out.

IMR4166 is a good powder and gives very accurate results if you get into the correct load range. I use it in my .308s, my .22-250s and in my .223s (for heavier bullets) with excellent results.

If your 6mm CM shoots H4350 well, I would try IMR4451 Enduron instead of IMR4166 Enduron with the 6mm CM. I use IMR4451 with my 6.5mm CM as well as H3450 and they are both very accurate with bullets from 130 to 147 grains. Their charges will be different but if you keep the muzzle velocities about the same, you won't see any real differences in accuracy. Any differences I've noticed are probably masked more by shooter induced variations than by the powders themselves.
 
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