.243 & 6mm questions, and the Colt/Sako Coltsman

[Col. Plink]

Hey y'all,
Just wondering if anyone can sum up the differences between .243 & 6mm in terms of most common bullet weights, velocity, and twist rates. The rifles I'm looking at are a Rem 760 6mm and a Coltsman (Colt barrel on a Sako L579 receiver).

Also, what would be the approximate value of the Coltsman in good/vg condition?

Thanks in advance!

 

[valkyrie.rider]

There really isnt much difference between them. You can find 243 ammo anywhere, but 6mm is a bit more difficult to find. Probably best to refer to a good loading manual for details.

 

[Art Eatman]

Bullet weights are the same. Velocities are very close to the same. The older 6mms were 1:14 twist, not stabilizing the longer/heavier bullets as well, maybe those 85 grains or less. Most .243s are around 1:10.

760? I'd have to look it up, for twist.

I have an L579 Sako Forester carbine in .243; great trigger.

 

[rcmodel]

I think the 6mm case is better for reloading if that matters.

Now, It's pretty much an over-the-hill cartridge unless you reload though.

The .243 Win would be MUCH easier to find factory ammo for anywhere.


The history:
Remington introduced the .244 Rem in 1955 as a heavy 'Varmint' caliber with a slow twist barrel for light varmint bullets.

The same year, 1955, Winchester introduced the .243 Win with a fast twist barrel as a 'light big game' caliber with the capability to handle heavier hunting bullets, as well as lighter bullets for varmints.

In 1963, Remington renamed the .224 Rem to the 6mm Rem with a faster twist barrel, to match the .243 with heavier big-game bullets.

Still in all, I would consider the 6mm a better caliber for reloading for top performance, due to the slightly larger case capacity, longer case, and longer case neck.

But only if you reload for maximum performance.

If you need to buy ammo at WallyWorld, the .243 wins hands down, going away, running backwards.

The 6mm already lost that race many many years ago!

rc

 

[243winxb]

Coltsman

I would go with the bolt action Coltsman. One was listed here for $700 with scope. More than i would pay. Condition is everything. http://www.armslist.com/posts/1801060/detroit-michigan-rifles-for-sale--colt-coltsman---sako-l579----243-bolt-action I have had Rem pumps and the Sako action. A new barrel can be put on the Sako, not so easy on the Rem.

 

[Chuckin' TV]

They are both really good calibers. The 6mm is harder to find, and depending on the year of the 760, the twist might be either 1 in 9 or 1 in 12. Remington gave a faster twist to stabilize 100gr bullets in order to compete with the 243. I'd personally go with the Colt depending on price. If you wanted a really accurate 243 just for utility, I'd go with a brand new Ruger American or Tikka and put a nice 200$ range scope on it.

The 760 is a good deer gun assuming the twist is 1 in 9.
I really recommend 100gr bullets if you trying to take a deer down at +100yds. The 760s offer acceptable accuracy with rapid follow up shots. But if I was to get the pump action, I'd go with a harder hitting caliber. I like bolt actions because I'm more a one shot one kill guy.

 

[Chuckin' TV]

As for velocity, the 6mm gains some but not enough in my book when you compare the availability of 243s. I just saw a Coltsman on Cabela's site for ~1100$ for a really nice one. That's probably a little high. I'm curious what you want a gun in one of these calibers for. Are you a collector? Or just want them to shoot target or hunt?

 

[bannockburn]

I would also go with the .243 for the easy availability of ammunition.

 

[1948CJ2A]

I'd rather have a 6mm Rem just to be different. If you handload you can get slightly improved velocities over the 243. Like others said, you'd want a twist faster than 1:14 though for longer/heavier bullets.

 

[Liberty1776]

I love the 6mm and have had several. Also have .243 which for me I've found to be more accurate with less fuss... I wound up with getting a couple .243 to pass on to my grandchildren for their general deer hunting needs...

 

[Corn-Picker]

To add some numbers to what people have been saying, a few minutes of research on Midway.com suggests:

The 6mm has about 60 ft-lbs more energy than the 243 at the muzzle
243 has 10x the ammo choices (60 vs 6)
- No lead free bullet options for the 6mm
- Least expensive ammo in 6mm is $25/box, for 243 it's $15/box

 

[Dr T]

As long as the rifle is less than 50 years old, there isn't enough difference to matter.

And 243 is a lot easier to find and usually less expensive when you do find it.

I have gotten stellar accuracy out of both. Back in the 70's I kept myself, my roomates, and several neighbors at UT-Austin fed with my 6 mm. It is a Remington 788 that I never intend to sell.

 

[Col. Plink]

Thanks for all the info!

It's funny; what I really want is a Rem 760 .243...

The 6mm 760 would round out my collecting bug for that model in a very 'Remington' way, but the Colt .243's tempting as way to rub out three unfilled areas: Sako, Colt, and .243

I'll let y'all know what happens...

 

[Jim Watson]

The original twist for the .244 was 12", not 14".
The heaviest factory load was a 90 grain flatbase spitzer.
Nosler made an 85 gr partition and you could load a 100 gr roundnose if you didn't worry about trajectory beyond about 200 yards.

But the Winchester rifle was lighter and prettier and the gunzines hyped its advantage in bullet weight.

Some of the late Remington .244s had 10 twists, as did some of the few makers to offer .244 besides Remington. No doubt cheaper for them to use the same barrel blanks for .243 and .244. This did not benefit anybody but handloaders who paid attention to rifle specs.

Remington reintroduced the cartridge as the 6mm Rem with 9 twist to be sure and handle 100 gr bullets.

Long Range shooters typically use an 8" twist for 107 gr boattail 6mm bullets. But few are using .243 or .244 chambers.

 

[Fred Fuller]

6mm vs. .243 was the caliber debate of, like, 1974

I bought a 6mm as my first centerfire rifle, a Ruger M77 that I ordered from the old J&G Rifle Ranch out in AZ (wonder what happened to those guys? )

Pretty much what everyone has said so far pretty well covers the current status quo...