I think remington was doing some 223 in then AAC guns threaded with a different twist for heavy bullets.
As for the 223/556 There were some cutting the chamber to use 556 and I was also told from AAC that 556 would be fin in there current bolt guns as for the throat.
Many of the 223 twist are done for light varmint bullets. The varmint is 1:12
The tac is 1:9 twist.
Those are for the Rem 700

 

The fastest twist I have seen in Remingtons is 1:9 for .223.

Tikka has some 1:8 twist .223 rifles which would suit the heavier bullet.

Savage has an F/TR with 1:7 twist but it's a $1400 rifle.

I'm not sure if it's an option as I'm just getting into Remington bolt action rifles myself, but you might be able to find aftermarket barrels in the length and twist you desire and either put it in yourself or have a gunsmith do it. That is, AFTER you test the 1:9 twist barrel with the 77gr bullets, because you never know, they MIGHT get along fine and produce groups for you. If it does work out...win-win scenario.

 

the 1:9 will shoot the 73/75/77's.....although the 68/69's do fairly well out to 500yds already. If you want to shoot the 75gr amax and 80's...you'll need 1:8....and the 90's require the 1:7 or faster

 

Oh yeah.....a 1:9 will shoot 77 gr SMKs just fine. Punched these out a couple of days ago..............

 

Oh yeah.....a 1:9 will shoot 77 gr SMKs just fine. Punched these out a couple of days ago..............

View attachment 60125

Nice groups. Varget?
Do you think they'll stay MOA @ 300yds?

 

No- I used IMR4064 for these. Soon as I can get about 200 yards of weeds knocked down, I'll let you know how they do at 300.

Another note- as was mentioned by GSRswapandslow- the 75 grain Hornadys need a 1:8 or 1:7. Out of my gun, they keyhole at 100 yds.

 

No- I used IMR4064 for these. Soon as I can get about 200 yards of weeds knocked down, I'll let you know how they do at 300.

Another note- as was mentioned by GSRswapandslow- the 75 grain Hornadys need a 1:8 or 1:7. Out of my gun, they keyhole at 100 yds.

The 77gr SMK prints under an inch and the 75gr hornadys keyhole? From the same rifle?

 

The 77gr SMK prints under an inch and the 75gr hornadys keyhole? From the same rifle?

The ogives are totally different; the 75gr AMaxs are long bullets. Not the direct comparison I was looking for but this will do:
http://www.ar15.com/archive/topic.html?b=6&f=42&t=380685

I know the OP was shooting a bolt gun so I'm not referring to him but 77gr smk bullets can be loaded to 2.26" magazine depth for ARs and a 75gr AMax has a limit according to Hornady of 2.39 or so... Recalling from memory, not actual data, of research I did when buying match bullets. The AMax needs a faster twist at that weight.

 

yes, the 75amax's are too long for almost ALL 1:9 twist barrels. When/if you get one...run a cleaning rod down it with a tight patch, and measure out the actual twist...if it's closer to 1:8, you might get away with it....if its' closer to 1:10, not a chance. Hornady does make 75gr bthp's...they worked fine in my 1:9 barrel. I've given up on my rem barrel though...mine is complete junk, even after rechambering to 223ai. I've got a barrel nut setup on the way now, from Northland...in 223ai 1:12

 

+1 for the 77gr Nosler CC. They do great in my 1/7 18"SPR.
Thats the reason i want a 1/7 bolt gun in 5.56.
I think with necksized brass, varget and seating them long it would be
a very accurate rifle.

 

The 77gr SMK prints under an inch and the 75gr hornadys keyhole? From the same rifle?

Yup- what they said ^^^^^.