6mm-223

[merl]

OK, here is a dumb ass I don't know crap question.

If the 6 and 5.56 (.223) both are 45mm in length and using the same bolt, what prevents one from pulling a Tard move like chambering a .223 or 5.56 and pulling the trigger in a 6X45 ?
I can see the oppisite of a 6x45 not fully chambering in a 5.56x45.

Nothing. Firing 5.56 in 6mm wouldn't hurt anything. I would not depend on the larger bore preventing chambering of 6mm in 5.56. It has happened with 300blk in 5.56 chambers...

[Colorado Osprey]

OK, another question. I am thinking of finally pulling the trigger on a 6x45 barrel in 18" but dont know what twist. 1:9 or 1:10? I plan on trying standard size .243 projectiles like 85grn plus or minus. not any heaver than 95grn or I would lose any advantage you gain over the 300BLK. I bought the dies already to start making brass and now I want to build the upper.

Most of the bullets larger than 85 grains will shoot, but will not feed from a standard AR magazine. I have a C-products stainless mag that lets me get a few more thousands of overall length to shoot 87's.
I shoot mostly 85's in a 1:10 20" barrel AR. BTW the 60 grain HP's are outstanding in both velocity and accuracy. They seem to hit coyotes way harder than a 62 grain bullet from a 223.

[XC700116]

Saw this thread the other night and stumbled across this today if you're still looking for a 6/223 barrel

http://forum.snipershide.com/options...rrel-dies.html

[buckshotbarlow]

MarkCO....Ok, u opened a can of worms here with a 260x45....What kind of shoulder are you going to run on it? I looked into the 25x45 and the bullets just sucked, plus availability....Have you thought about taking a 6x45 and giving it a ackley shoulder? I got a virgin 6x45 tube we could play with...

[hghclsswhitetrsh]

I'm trying to track down a barrel now. Yipppeee

[MarkCO]

MarkCO....Ok, u opened a can of worms here with a 260x45....What kind of shoulder are you going to run on it? I looked into the 25x45 and the bullets just sucked, plus availability....Have you thought about taking a 6x45 and giving it a ackley shoulder? I got a virgin 6x45 tube we could play with...

I settled on the 6.5 PCC. It has some support in reamers and dies, but no-one has really pushed it yet. The guys who have not liked it, IMHO were not using the best combinations of powder and bullets. Granted, it is an experiment for me and I might end up coming back to the 6x45. But my calcs tell me I can run the same bullet mass at about 150 faster than the 6x45. We will see if it bears out in reality.

With matches and projects, might not get it done until June or so...the 450 Corvette parts head out to Cerakote next week, then tuning.

[hghclsswhitetrsh]

What's the average life expectancy of one these barrels?

[buckshotbarlow]

i run my 75gr vmaxs at about 2600fps. My 20" doesn't get shot a whole heck of a lot time anymore since my range is shutdown and in a cluster f*ck of status about reopening. I have about 250rds down range and I think that the life of the tube will be very high because of the low speeds. BHW is a poly3 grove barrel, so i'm not worried about the rifling wearing down...I'm thinking about giving this round an ackly treatment to get some more velocity and case capacity...might have to start looking for a new reamer.

Here's our other post, might want to have the mods do a merge...

https://www.ar-15.co/threads/46001-6mm-223

[buckshotbarlow]

i guess the 6x45ackley is the same as the 6tcu...
http://www.6mmbr.websitetoolbox.com/post?id=1770476

[buckshotbarlow]

well, now i found a reamer...
http://www.z-hat.com/ReamerList.htm