243 or 6mm

Boomer said:
I talked to Marshal about a heavy 6mm and a heavy .257 to push them into 6.5 category, but he didn't believe the sales would cover the cost of tooling up. No hard feelings from me, Marshall has treated me well over the years, and he sits high in my estimation.
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Seeing this 6mm/243Win debate has gone twist talk, I'll stick with Boomer's observations on twist versus velocity. C-FBMI's idea on the increased friction and internal drag caused by the very fast twist does have merit and in itself is correct, however in my experience when you put the same bullet with the same charge, case and primer behind varying twist's, I believe what is lost with the increased resistance in the faster twist, is offset by the pressure curve staying higher longer through the bore producing similar velocities in the end.

In regards to the 6mm/243Win debate,....the 243Win is the darling, proven, pretty and readily available and desired. The 6mmRem is superior in everyway, and more for the purist. Superior insamuch as it does things a little better with light bullets and marginally better with heavier, providing the twist rate is correct,...and here we are back to twist rates again.


Twist rate is only one part of the equation and I find there is a lot of focus on the turns per inch over all other things. It's bullet RPM that matters. A given length projectile requires it to be spinning at a given rotation to be stabilized fairly quickly. It can be accomplished two ways, keep the same twist and increase velocity to accommodate the heavier and normally longer projectiles i.e. 243Win upgrade to 6mm, or keep the same engine and increase the twist rate. Either way you are adjusting the RPM of the bullet. Some say there is a sweet spot for every bullet, spinning not to fast or not to slow. I believe this to be correct at short distances for bench rest guns under 200 yards. If long range is your game I'd say go a little toofast than a little too slow. As boomer pointed out, that extra rpm way out in trans-Siberia zones, that extra rotation will help overcome the upset we see in the transonic region.
 
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interesting the way this thread has gone, I have both, a BLR takedown in .243 in Nz, I take for fishing trips, and as a truck gun when traveling,
And a bought one, of the Remington 700 CDL limited edition, 6mm Remington's from a few years back, Fantastic rifle, shoots most everything well, currently have a varmint load with 65 V-max, and 85gr partion both at full throttle, and same point of impact, at 200m, with 1.5" five shot groups, Shoots the Hornardy 87 BThP even better, but point of impact is 4" below the varmint load. at 200m, I like the 6mm, found this one easy to load for and accurate.
 
I have had a standing "love" affair with the 6mm Remington since about 1968. So much so that I have had
to rebarrel at least 5 of them at least once, lol.

At present I have 3, two are sporters [One an old flat-bolt Ruger on it's second barrel, the other a Remington 700 Classic]
The third one is one of my 1000 yard rifles, with a very heavy Benchmark, 1-8" twist on a 700 action, built by Leeper.

I have shot a railcar worth of deer with the 6mm, and also a couple of moose.
[not recommending it as a moose chambering, but when opportunity knocks, and that is what is in your hands.........:)]

I like the longer neck and sharper shoulder of the 6mm vs the 243, but really, there is not a huge difference between the two. [possibly 100-150 fps with 100/105 grain pills]

As has been suggested previously, the 6mm is largely a handloaders game, while 243 factory ammo is plentiful and varied.

Your choice will depend mostly on what you plan to do with the firearm. Regards, Dave.
 
Trapper_Jo said:
yes I been trying to acsess that EE for very long time can someone help !
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There is a link at the top of the EE section... click on it and go through the introduction process and wait for moderator approval... it only takes a few days.
 
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