g n brezinski
Member
saw this in a old rifle magizine cover.it was created by harvy miller from california.any one play with this in shooting amtches any .what is it based on ?thanks for your imput.
gary b
gary b
6 mm mcr case
- Thread starter g n brezinski
- Start date
6 mcr
The 6 MCR was a cartridge developed by Harvey Miller back in the 70's. The cartridge was based on a shortened and necked down 30-30 case. Harvey used this cartridge to set a new record agg. of .1629" which was the first ever sub .2" agg. back around 1980. I do not have any case dimensions. Harvey also made a 22 caliber version, the 22 MCR. Harvey's 6 MCR rifle is on the cover of Rifle magazine, November 1976 issue 48. I do not know if this issue gave any details of the cartridge, but suspect that it does. See attachment. It is a partial only, because I don't have a subscription. The second page has "about the cover".
Michael
The 6 MCR was a cartridge developed by Harvey Miller back in the 70's. The cartridge was based on a shortened and necked down 30-30 case. Harvey used this cartridge to set a new record agg. of .1629" which was the first ever sub .2" agg. back around 1980. I do not have any case dimensions. Harvey also made a 22 caliber version, the 22 MCR. Harvey's 6 MCR rifle is on the cover of Rifle magazine, November 1976 issue 48. I do not know if this issue gave any details of the cartridge, but suspect that it does. See attachment. It is a partial only, because I don't have a subscription. The second page has "about the cover".
Michael
Steve Kostanich
Active member
Harvey Millers MCR series was a case somewhere in between a 219 Daonaldson Wasp and Harold Broughton's 240 Coyote #2 with either a 22 or 6mm neck.
Both based on a 30-30 case, but could also be made from 25 and 30 Rem cases, which are rimless and are very close to a PPC head size.(but lousey brass!)
FWIW
Steve Kostanich
Both based on a 30-30 case, but could also be made from 25 and 30 Rem cases, which are rimless and are very close to a PPC head size.(but lousey brass!)
FWIW
Steve Kostanich
Steve,
I also read that Harvey also used 225 Winchester brass. While all of the cases, including the rimless Remington's are all 30-30 based, the 225 Win has the same rim diameter as a 308 or 30BR, while the rimless diameter brass is about .418" diameter. The 6.8 SPC opens up a whole new option for rimless 30-30 brass that is already 222 Rem. length. The best new option for a rimless 30-30 based BR case is the 224 Valkyrie made by Federal. It has an overall lenght of 1.6", and nails the capacity of the 6PPC. The 6mm Valkyrie would be very interesting. Even better if Lapua does decide to make the brass. I have heard directly from Lapua that they are considering making it. See below. Made by Starline brass.
Michael
Attachments
Steve Kostanich
Active member
Mike,
Have you seen the 224 Valkyrie that Federal has come out with for the "Black rifle" guys. If the brass is good, it may have some possibilities for BR w/ a 6mm neck, and shortened up a bit. The June American Rifleman has an article about it.
I forgot about the 225 Win that Harvey used for th MCR series, thanks.
Steve Kostanich
Have you seen the 224 Valkyrie that Federal has come out with for the "Black rifle" guys. If the brass is good, it may have some possibilities for BR w/ a 6mm neck, and shortened up a bit. The June American Rifleman has an article about it.
I forgot about the 225 Win that Harvey used for th MCR series, thanks.
Steve Kostanich
Steve,
I have not seen it in real life. I have only seen the pictures, like the one I posted above. I do know the length is 1.6", and I do know that this length duplicates the PPC case capacity. I know this since I shortened a 6.8 SPC from 1.680" down to 1.600" and necked it down to 6mm. I posted this cartridge back in April of 2008 here on benchrest central. Kevin from Lapua is the person that told me that the 224 Valkyrie has been discussed for production.
See original thread here: http://benchrest.com/showthread.php?51798-22-BRT-and-6mm-BRT&highlight=
