223 bore size

[jsthntn247]

Every barrel for a 223 centerfire Ive had was a 219/224. Anyone ever try anything different for shooting heavier bullets? You can get 298-300 for 30 cals and 236 or 237 for 6mm but I can't say I've ever thought about it for the 223

 

[watercam]

Give the cut-rifle barrel makers a call and see. No reason they could not accommodate you.

 

[XTR]

I've asked. The cut rifle guys I've talked to told me they weren't set up to over bore in either 224 or 308.

 

[Rob01]

Have you checked with Bartlein? They do a .218 .224 barrel.

http://bartleinbarrels.com/calibers/

 

[jsthntn247]

I've asked. The cut rifle guys I've talked to told me they weren't set up to over bore in either 224 or 308.

Were you thinking of trying a 220/224?

 

[Ned Ludd]

Have you checked with Bartlein? They do a .218 .224 barrel.

http://bartleinbarrels.com/calibers/

This is what I have on all 3 of my .223 competition bolt rifles (Bartlein - 0.218"/.224"). I can't imagine why you'd want to go the other way (i.e. up from .219").

 

[XTR]

Lower pressure with heavy bullets and long bearing surface

 

[jsthntn247]

Figured it might produce less pressure as XTR said. Only 220/224 I've found is Green Mountain Barrels.

 

[XTR]

My theory, that I was willing to test, was that the long bearing surfaces didn't need the .003 depth in the lands to impart rotation into the bullet with out slippage, and that the result of going to a .301 or a .220 bore would lower pressure and allow for more powder charge for a given chamber and bullet configuration resulting in better velocity.

The idea being sort of like what happens with a moly or hBN coating. For a given powder charge you get lower velocity with coated bullets, but you can get more powder behind them and run a longer pressure pulse and usually achieve more velocity. (whether or not the gain is worth the trouble there is another discussion)

 

[Dgd6mm]

Looking for an update if there is any to this question. Say I want to run an 88 -90 grain bullet out of a 30" barrel with the .223 cartridge. Wouldn't I want a 219 bore?

 

[BP1]

Looking for an update if there is any to this question. Say I want to run an 88 -90 grain bullet out of a 30" barrel with the .223 cartridge. Wouldn't I want a 219 bore?

Yes

 

[Dgd6mm]

Thanks for the verification.

 

[Ned Ludd]

Looking for an update if there is any to this question. Say I want to run an 88 -90 grain bullet out of a 30" barrel with the .223 cartridge. Wouldn't I want a 219 bore?

Another "yes" to this question. If you're going to be shooting heavies out of a 30" barrel, especially those known to have jacket failure issues out of [tighter] 0.218" bore barrels, the general consensus is that the 0.219" bore largely solves these problems. Brad's original post was asking whether something beside a 0.219" bore dimension was even a possibility.

In terms of jacket failures, it appears as though there are a number of contributing factors. First and foremost is obviously friction, so the issue will be exaggerated in longer barrels (28-30" and longer). In barrels of 26" or less, it may not even be an issue in the first place as the velocities achieved and the friction produced don't appear to be nearly the problem that they are in the long barrels we use in F-TR.

It is also important to note that when using a long barrel (28-30"+) with the tighter 0.218" bore, other factors such as the barrel twist rate and land/groove configuration also become critical. For example, I have never lost a bullet jacket in a 30", 0.218" bore, 5R, 7.0-twist barrel. However, going to a slightly faster twist rate (6.8-twist), otherwise with the exact same configuration was apparently the straw that broke the camel's back, and I started losing bullets immediately. Others using 6.7-twist to as fast as 6.5-twist barrels have noticed the same thing. Those twist rates become contributing factors to jacket failure in the tighter 0.218" bore, as can barrel land/groove configurations that are harder on bullet jackets. A number of shooters have found that simply going to a 0.219" bore can largely alleviate the issue of jacket failure. Further, with a 0.219" bore, faster twist rates such as 6.8-, 6.7-, or even 6.5-twist, no longer seemed to be the contributing factors they would be in a 0.218" bore barrel. So if you're planning on running the heavies out of a long barrel such as used in F-TR rifles, a 0.219"/0.224" configuration is what you want.

 

[PracticalTactical]

It would be an interesting niche market for a home bullet maker to try making bullets in various diameters so guys could test for best results with their particular barrel configuration.

At least we would not be painting ourselves into a corner with an experimental barrel that may not work well and have no use for afterwards if we don't like it.

Could even be that we could chase barrel wear with ever fatter bullets over the life of the barrel. Maybe a ~ worn out ~ barrel is just worn out for the standard bullet sizes.

 

[PracticalTactical]

Thinking about this, Gary Schneider might be a guy you'd want to speak with. He once made me a polygonal barrel for a 6x47L and that thing was out of this world. It had short barrel life but it compensated for it with accuracy.

In speaking with Gary, he told me stories of experimentation that he was involved with for the military that were intriguing. I'll bet he'd have something to say about all this.