B.C of 120gr. 6mm bullet from Richard Graves

[308 nate]

I was wondering if any of you have a guestemation of the B.C of this bullet. weather it be real life or just a computer#
I am planning on having a reamer built especially for this bullet and would like to have a guestimated B.C number to play around with.

I talked to R.G and ordered 500 bullets from Him 3-4 weeks ago and asked for a guestimated B.C and he didn't want to give me one and I didn't want to pry. As I knoe it is a touch subject for Him. So any help would be appreciated.
thanks,
308nate

 

[brian b]

I am guessing it would be somewhere in the .600 range give or take a little but the question I have is what twist barrel does he recommend? (1-6" ?).
B

 

[308 nate]

brian b,
I'm thinking a 1 in 7 will do it.If I remember correctly He said the computer called for a 1 in 6.9 but He thought a 7 would do it.The case I'm thinking of basing off of is the Lapua 6.5x55 necked to 6mm and then improved.
I'm thinking 30-32" barrel with 6" barrel block and McMillans F class low pro stock for shooting f class and possibly 1,000yd bench rest.But I'm still in the dreaming stage for this one. Any ideas for velocity for this case?
I'de like to see 3200 FPS.
thanks for your reply,
308nate

 

[abinok]

308 nate,
some time back I was trying to get some documented bc's for some of Richards bullets, and HBC over on BRC said he would be interested in testing some, and providing some solid BC numbers. There were some other shooters on this board who offered to test some 30cal's as well, but HBC is set up only for the 6mms.
Is the cost of a few bullets worth having reliable data to you?
You can get his contact information from his profile over at BRC, or id be happy to provide it if you are interested.

 

[sniper2]

Brian I am sending a chart for minimum twist rates for you to look over.

 

[308 nate]

abinok,
If it's no trouble,the contact info would be apreciated as I might consider doing that.

I guess here is my feelings on B.C I would be plumb happy with what the computer figures B.C is. I feel it is pretty acurate
even having someone do a real life B.C analysis could be different than the B.C I would get for there are so many things that can change the B.C,such as number of lans, design of lans,humidity,altitude and so on and so forth.And then there are things that can fool us into thinking the B.C is off such as inacurate cronographs, inacurarate range finders and inacurate balistic programs or just not entering all the variables Etc,Etc....
I still do a complete,real life drop chart with my rifles.

in other words I would'nt hold anybody to the number, I just want a number to play with.

308nate

 

[308 nate]

just clarifying I did not buy any of the 120gr. bullets yet. the 500 bullets were some 30 cals and some 6.5 and 7's

308nate

 

[Centre Punch]

nate,
see if you can find any info on the 6mm Vais,(6.5x55 necked down and improved). This cartridge loaded with 54 to 56 grains of H1000 will launch a 107 SMK at 3360fps.
(From the book "Precision Shooting at 1000 yards")

Ian.

"I mean't to shoot the pike but the duck got in the way"

 

[sscoyote]

Yeah, there were some writeups on that cartridge in PS awhile back.

 

[abinok]

Nate,
email sent