IMR 4166 in 6BR

[larmike]

I was able to test a little this morning with the new IMR 4166 powder using some SMK 107GR. and some custom made 106gr. projos. I first loaded 5 rds of 30.0gr. of varget and 30.0 grs. of the 4166. The 5 rds of varget loaded ammo made a nice ragged hole and the following 5 rds. of the 4166 load followed in the same group with no noticeable variation of the group size.
Unfortunately my chronograph did not register any of the 30.0 gr loads. So I decided to try 30.5 gr. of the 4166 based solely on that I won a 3x600 with 30.5 gr of Varget with a Berger Hybrid. The chrono finally decided to start picking up the bullets velocity, the load of 30.5 gr. of 4166 was 2943,2945,2948. I use a Bartlein 1-8 twist 30in long mounted to a Barnard P Action.

Once I found the jump sweet spot 0.025 with the SMK 107gr. and .010 for the custom projos. the 3 rd group was basically a 6mm hole. Yes I know that is not a true test of the load, but I was running out of time and I will do a 30 rd test at 300yds. as I would shoot a match prone with a sling and iron sights.

The powder is for as far as I can tell it very close to varget, the copper fouling eraser, well I dont know if it works or not as I coat the barrel with HBN.

 

[CaptainMal]

Thanks for the information. I did a post on my testing with a Dasher. It's on the reloading forum. Same results in velocity. Did not test for accuracy as I'm not going to use it with the current barrel.

 

[NZ_Fclass]

Having low supplies of Varget ( it really is made from Hen's Teeth) I have been playing with 4166 in 308 with "some" success. Long story short - I recently bought a 6 BR, so with some awesome winter weather, sun and little wind headed to a friends farm to do some initial load testing. There's not much data around, but the experience with 308 have me a guestimate at 28g with a 105 Hornaday.

Happiness started with 28g and finished at 28.2g. The group below is 5 shots at 100 meters ( we are quite metric down here in New Zealand). Barnard P action, Tru-flite barrel, XLR Stock, Falcon 10-50 X50 scope. New Norma brass. 15 from the lands. Not sure of the speed. Next testing session will be a bit more serious, now first testing is done. Patch is 25mm. Group measured just under .462 MOA. Outside to outside. I'll take that.

 

[AR10T308]

Thanks for taking the time to post this. I too recently purchased some IMR 4166 given I have not been able to find Varget anywhere for over a year now, AND I was hoping it would work in my 6 BRs in place of the unobtainable Varget. I will be starting at 28 as well and working up from there.

 

[rijndael]

The powder is for as far as I can tell it very close to varget

And 4064. My 4166 308 load is only .1 grain off from my 4064 with identical chrono numbers.