which 6mm?

[grit]

Well, I ran the numbers.

The 105 bucks the wind better by about 1 moa at 1000 in 10mph wind. The 87 is flatter by about 4 moa at 1000. I suppose the 105 offers a slight consistency advantage by bucking wind better.

Sooo, I like the CZ a bit better. The remington offers the versatility to shoot the 105. What I don't know is how the 1 in 10 handles 95's and 100's.

 

[LB]

I think you would be running right on the ragged edge with the 105 in the CZ. It depends on the profile and the bearing surface, but if you are locked on that particular bullet, it may not work? Another thing that is unclear to me is, what chambering are you talking about? 6MM or 243? Isn't a 1-10 twist standard with a 243? Just ask 243 shooters if they have tried it, and if it works? The 6MM, even with a 1-10 might have enough velocity to stabilize since it can be driven a little faster?

Good hunting. LB

 

[Buffalobob]

[ QUOTE ]
Ultimately, top priority is to stabilize an effective hunting bullet, for deer

[/ QUOTE ]

You will be shooting mule deer which are bigger than the eastern whitetails which I shoot.

A 1-10 twist will stabilize "conventional" 100 grain bullets such as the Sierra 100 gr boattail spire point which has a BC of 0.430. This would be the bullet of my choice for muledeer.

Radical designs such as the 95 Berger will probably not stabilize in either gun.

I have used the Speer 85 gr SPBT at high speed (240Wby) for many years at close range on whitetails and the bullet is well made and always exits. It has a BC of 0.404 which is pretty good. It is designed for deer and works on the small deer I shoot. I have also used the Barnes XLC in 85 grains and it is fast as advertised. Not real accurate but good enough for deer.

I haven't run the numbers on a 6mm at the slower speeds, but long range shots for deer will be about 500yds no matter what BC bullet you shoot. The cartridge just does not have the horsepower to get it done "reliably" much further on out. How far you want to shoot a deer with the gun is up to you but it is not a 1000yd deer gun even with the big three -6-06, 6-284. and 240wby.

 

[grit]

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 /ubbthreads/images/graemlins/smile.gif. 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. /ubbthreads/images/graemlins/cool.gif

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.

 

[Aussie]

Grit ,
My advice would be not to choose a rifle based on a supposed ability to shoot one bullet . There's no guarantee that the 105 A Max will shoot accurately in the Remington regardless of twist .
A sporting weight deer rifle in .243 that will shoot well at 1000 yards and cost less than 700 bucks is a big ask .

 

[royinidaho]

Grit,

Was snooping around, found this.

REM VLS 6MM

 

[grit]

Quite a nose you've got there Roy. I'll have to get one of those. I bought the CZ today! Now I need a scope...