one of the guys i work with ssays hes got 4200 with a 75gr vmax. im not to sure if hes full of you know what though. if thats true i think you should be able to get some where around 3400-3500 with the 120s. but dont know for sure.
I looked at this real hard when I was looking to design a 6mm AM. I decided to pass on it as the case capacity to bore volume ratio scared even me off a bit. The reason is because the big 6mm wildcats we have today are already pushing past what the current heavy bullets will handle accurately.
If Richard could get some heavy jackets on a 120 gr bullet it would work well but there are several issues you would have to deal with. Only Ball powders could be used because of powder bridging problems.
Also, powder fouling would be a serious problem, you would need to stay on top of the carbon fouling all the time.
velocity swings will be severe in most cases with changing temps with the powders which would be appropriate for this type of chambering.
In the end, just more issues then I wanted to deal with.
About the same thing I found with my 224 AM in testing it but even to a higher degree.
If it were me, if someone wanted more performance then a 6-284 or a 6-06, I would look harder at the 6mm SAUM as its case capacity is a bit less but still more then anything else out there. Only problem there, brass will likely get hard to find down the road as I see it being dropped from the Rem line sooner then later.
Think of it like a 1000 hp blown V-8 in a lightweight camero, wild as hell, hard to control but if you get her going in a straight line, will whoop on anything else out there!!!
Allen Precision Shooting
Home of the Allen Magnum, Allen Xpress and Allen Tactical Wildcats and the Painkiller Muzzle brakes.
I had the same plans for a 6-300 with the 117 dtac's in mind. I was thinking and punching numbers and those puppies at 3600 + fps would be awesome for western coyotes. However it sounds like 1.) they cant take the velocity and 2.) its to overbore to get to those velocities.
Oh well back to the drawing board, maybe i'll but the project on hold until there is a little more disposable income. The 257 wsm sounds like a possible winner but wouldn't give much more than several quarterbore wildcats out there.
looks like it will be a 6-284 for my next savage barrel, dont really want to go the route of the rsaum although it would have a little edge on the 284.