AR vs 223 bolt gun ?

[rebs]

I have read on different forums that a 223 bolt gun can be loaded a bit hotter than an AR.
Why is that ?

 

[people]

gas port pressure. Basically all AR's are over gassed then putting even more into the system will cause problems like tore rims and excessive ware.

 

[Mark M.]

SLR makes a very good adjustable gas block

 

[2506]

Along with gas pressure it is PSI pressure. The AR platform is designed to operate at 50,000 PSI if memory serves me. Up the pressure some and over time it will beat the rifle up and you will have bolt failure problems. With the AR platform you are also limited to magazine length. COAL usually 2.250 or under. With a bolt rifle it will handle more pressure safely without eventually braking things and with most you can load to a longer COAL and that in turn gives you more case capacity.

 

[Metal God]

Give me a second , I’m gunna go get the popcorn.






Ok , I’m ready

 

[jelenko]

Give me a second , I’m gunna go get the popcorn.






Ok , I’m ready

 

[rockhound78]

IIRC, 5.56 Nato ammo runs about 55-60K psi. I am thinking you could go a bit warmer with a good bolt gun but you would batter the gas system in an AR style gun and risk a bolt fracture or other damage. An adjustable gas block might help, but I have no experience there. You might be able to maybe go to 62 to 65K psi in a bolt gun, but I would think you might not gain much in performance, but I would think that you might run into some limitations of the brass. Expanded primer pockets possible.

Military runs 5.56 Nato spec ammo in the M-16's and variants, but if something breaks, Uncle Sam pays for it.

 

[Richard Coody]

Lots of better cartridges for ar's than 5.56. 6.5 grendel and all it's wildcat.cousins for a start.

And certainly a bolt gun. First I would pick would be a 6br for.anything you might use a .223 for. 6br also has many cousins.

 

[Deleted outa08]

Give me a second , I’m gunna go get the popcorn.






Ok , I’m ready

Any left?

 

[Metal God]

Ok I’ll play , ask your self this . If 223 can be loaded to higher pressures. Why is it recommended NOT to shoot 5.56 in 223 chambers ???? Duh !

Remind me again what firearm the 5.56 nato cartridge is designed to be fireded in ???? Duh Duh !!!!

 

[std7mag]

And so it begins.....



Wait!!!
That's all the butter your putting on the popcorn!!??

 

[Uncle Ed]

My Savage .223 with a 1in9 twist has a longer throat than my AR15 rifles and can be loader warmer than short throated 1in14 and 1in12 rifles.

And my bolt action Ruger Ranch rifle is marked 5.56 1in8 twist with a longer throat.

If you look in the manuals the load data for the .223 has a short throat with 1in14 and 1in12 twist rates. And the .223/5.56 intrchangability warning came out when the military went to the M885 round and rifles with a longer throat.

The main differance is throat length and both the .223 and 5.56 are rated at 55,000 psi SAAMI pressure standards.

 

[Metal God]

I know the difference but if the 556 is naturally loaded to lesser pressure/charges the shorter throat in a 223 shouldn’t matter
DOH

 

[jepp2]

With the AR platform you are also limited to magazine length. COAL usually 2.250 or under.

Without modification to the magazine that is exactly correct. However if you cut a window in the front of the magazine I have loaded to 2.370" OAL. Limitation becomes the lower mag well. I use a steel magazine, and only cut the window for 5 rounds. With a sled there is no lenth limit as long as you want single loading.

 

[Uncle Ed]

https://saami.org/faqs/#ammunition-firearm-chambered
Can I use 5.56x45mm, 5.56 or 5.56 NATO ammunition in a firearm chambered for 223 Remington (223 Rem)?

NO!

It is not safe to shoot “5.56” “5.56 NATO” or “5.56x45mm” (“5.56”) ammunition in a firearm with barrel marked as being chambered in 223 Remington for a number of reasons. The main reason being that a barrel marked as chambered in 223 Remington will have a shorter throat into the rifling than a “5.56” barrel which may cause increased pressure when the “5.56” ammunition is fired in it. This can result in serious injury or death to the user and/or bystanders, as well as damage to the firearm.

However, it is safe to use SAAMI-compliant 223 Remington ammunition in firearms with a barrel marked as chambered in “5.56.”


Below Military requirements for the 5.56 using SAAMI testing standards for chamber pressure (55,000 PSI)

 

[jelenko]

Wait. What about 223 chambers designed to handle hotter loads - I'm thinking of Wylde as an example.

 

[whatsupdoc]

What about this guy. .223 5.56 German Green tip

 

[Metal God]

Ed you just made my point . 223 must be loaded to lower pressures or you couldn’t fire them in a 223 chamber , err wait what ??? lol

 

[Bill K]

Ok I’ll play , ask your self this . If 223 can be loaded to higher pressures. Why is it recommended NOT to shoot 5.56 in 223 chambers ???? Duh !

Remind me again what firearm the 5.56 nato cartridge is designed to be fireded in ???? Duh Duh !!!!

It is the fact of the neck/lead length in the standard .223 chamber as compared to the 5.56 chamber that is the reason not to fire 5.56 in the standard .223 chamber. Look at the specs on each. If you want to fire either, then you need the chamber spec that allows safe firing of either.

 

[Metal God]

Bill we/I'm past the leade understanding . It's the longer leade in the 5.56 chamber that allows you to load to higher pressures/charges .

As for gas pressure that not only can be controlled by an adjustable gas block . It can be controlled by the burn rate of the powder . A faster burn rate like 4198 will not have the same pressure at the gas port that lets say Varget , W-748 , CFE 223 will have . It's the very reason some have cycling issues when using 4198 . You also won't get as high a velocities with 4198 even though you're reaching the same max pressures .

My popcorn is getting low