Re: which 6mm?
Thanks Bob and LB.
This has been a learning experience for me. I started with a desire to shoot something smaller, which would still stretch out for varmints and targets. My wife also happens to need a deer rifle. When I saw the .5 bc of the 105 a max with velocities in the 3100s for the 6mm and the 243 wssm, I was impressed.
I next started looking at rifles. In doing so, I was a bit surprised to find most of the wssm rifles have short barrels? I was surprised further to find a sporter weight 6mm virtually unavailable.
I like the 243 win as well, so I figured I might as well look at them. Lots of 243's. While looking at the different rifles availabe, I realized the 1 in 10 twist wouldn't stabilize the 105's at 243 speeds, and maybe not at wssm and 6mm speeds. This led me to wonder where the edge was. Could a regular 243 win even shoot the 95 and 100 grain deer bullets well?
The rifle twist is a new aspect for me. I must admit to feeling a bit bewildered. I wondered why the standard twist for a 243win is 1 in 10, and remington and savage chose a 1 in 9.25. Just for the 105? Or for 95's and 100's at slower speeds?
I found a chart on Dan Liljas website with recomended twist rates for various calibers and bullets. He suggests a 1 in 10 for up to the 100 grain mark. And a 1 in 8 for the 105 and 107's.
I have found a few programs and formulas which will predict optimum twist rates for a given bullet and velocity. They all require detailed measurements I don't have.
My purpose, for the moment, has become dual. To pick a new rifle [img]/ubbthreads/images/graemlins/smile.gif[/img]. And to understand the effects of twist rates.
As to the rifle, my choices at the moment are a remington or a cz. Both are chambered for the 243win. I like the feel of the cz a bit better, but it won't handle the 105. Apparently the only advantage of the remingtons faster twist is the ability to handle this one bullet??
My thoughts at the moment are, the advantage of the 105 is pretty slim for long range target and varmint. And, it's not a hunting bullet. So, I can live without it just fine, and live happily ever after with a 1 in 10 twist.
Or at least have a good excuse to add the big remington in 6mm to the collection at a later date. [img]/ubbthreads/images/graemlins/cool.gif[/img]
About the 6mm rem:
The 243's seem to serve three primary purposes.
1. light recoil deer rifles
2. long range varmint rigs
3. making itty bitty groups
Seems to me, the 6mm rem would at least do the first two better than a 243win. So, Where are they? If The rifles I liked were chamberd in iether the 6mm rem or the 243wssm I would prefer them to the 243 win. I guess I'm lamenting the scarcity of the 6mm rem.