reloading for 223/5.56 questions

[Bigeclipse]

New to this round but not reloading in general. I know 5.56 is basically a 223 with a bit more pressure. I recently started shooting a mini 14 which I really like and would like to start reloading for it and make up several loads. one load for cheap plinking, another load for accuracy/hunting out to 300 yards and a third load for maybe house defense although I am not sure id want to be using a 223 for defense but who knows.

So first question, should I not even bother with 5.56 pressures and simply stick with 223 loadings (my mini 14 is stamped 5.56 on the receiver so it can handle it).
Second question, which bullets for coyotes out to 300 yards and last question is which rounds (if any at all) for home defense. Was thinking maybe V-max since they do not over penetrate. Any thoughts or things im missing?

 

[bigedp51]

Both the .223 and 5.56 are loaded to the same exact chamber pressure of 52,000 cup or 55,000 psi. The pressure confusion comes from where the pressure traducer is located for the European CIP (NATO) pressure readings and reads as 62,000 psi.

Below the specifications for the M855 5.56 round. (55,000 psi SAAMI transducer method)

The SAAMI interchangeability pressure warning between the .223 and 5.56 came out in approximately 1979 when the military switched from the M193 round to the M855 round and lengthened the throats on the M16 rifles.

The problem is when the military M855 round is fired in the shorter SAAMI .223 throat the the chamber pressure will be approximately 5,000 psi higher.

Now to add even more confusion, the throat in my Savage .223 with a 1 in 9 twist is longer than the throat in my AR15 rifles. Many of the rifle manufactures today are making the .223 chambers with a longer throat. This makes plenty of room in the chamber for the cartridge and the company lawyer and also lowers the chamber pressure.

Also note that military brass like Lake City is made harder in the base than any commercial .223 case. Meaning Lake City brass is the best brass the American tax payers can buy.

The 5.56 cases were made harder to help prevent the jamming problems the early M16 rifles had.

 

[Bigeclipse]

Both the .223 and 5.56 are loaded to the same exact chamber pressure of 52,000 cup or 55,000 psi. The pressure confusion comes from where the pressure traducer is located

Wow...lots of info! Thanks for clarifying some things for me.

 

[tomt]

bigedp51,

What a great post, thanks for taking the time to put it together.

Tom

PS, I'm saving it to my favorites.

 

[bigedp51]

I buy a lot of once fired Lake City cases, because they have the hardest brass in the base and their quality. The Lake City and commercial contract cases made for the military have a thicker flash hole web which greatly strengthens the base of the case.

Below a .223 case has a thinner flash hole web and the primer pockets will become oversized much sooner. So just remember Lake City cases are built Ford Truck Tough.

Below is an excerpt from CatShooters posting on brass hardness At AccurateShooter.com. I was in a "discussion" with someone about .223/5.56 case hardness and CatShooter posted the Rockwell hardness of the cases.

[FONT=&quot]The actual Hardness measurements were (.062"x100kg, Rockwell "B")[/FONT]

[FONT=&quot]LC 2008 = 96[/FONT]

[FONT=&quot]Lapua 223 Match = 86[/FONT]

[FONT=&quot]Norma 30-06 - 76 (added n Dec -'14)[/FONT]

[FONT=&quot]Winchester 223 = 69[/FONT]

[FONT=&quot]Norma .220 Swift = 64 (added in Dec '14)[/FONT]

[FONT=&quot]Remington "R-P" = 49[/FONT]

[FONT=&quot]For all you guys that have been saying that Winchester cases were tougher than Remington... you are vindicated, they are a lot tougher!... 40% tougher[/FONT]

[FONT=&quot]For all you guys that think Lake City is surplus junk, nothing could be further from the truth. It is some of the most bestest brass made (it is paid for by the tax payer), so enjoy it!!![/FONT]

[FONT=&quot]LC and Lapua are the "The pick of the litter"!


[/FONT][FONT=&quot][FONT=&quot]The best part is these Lake City cases are made harder [FONT=&quot]and not thicker like our 7.62 cases. And the[FONT=&quot]y also[/FONT] have the most case capacity.[/FONT][/FONT][/FONT][FONT=&quot][FONT=&quot][FONT=&quot]

[FONT=&quot]

[/FONT][/FONT][/FONT][/FONT][FONT=&quot][FONT=&quot][FONT=&quot][FONT=&quot][FONT=&quot]The above postings were brought to you b[FONT=&quot]y a retired old fart with nothing to do and all day to do it.[/FONT][/FONT][/FONT][/FONT][/FONT][/FONT][FONT=&quot][FONT=&quot][FONT=&quot][FONT=&quot]
[/FONT]
[/FONT][/FONT][/FONT]

 

[rcoody]

Both the .223 and 5.56 are loaded to the same exact chamber pressure of 52,000 cup or 55,000 psi. The pressure confusion comes from where the pressure traducer is located for the European CIP (NATO) pressure readings and reads as 62,000 psi.

Below the specifications for the M855 5.56 round. (55,000 psi SAAMI transducer method)

The SAAMI interchangeability pressure warning between the .223 and 5.56 came out in approximately 1979 when the military switched from the M193 round to the M855 round and lengthened the throats on the M16 rifles.

The problem is when the military M855 round is fired in the shorter SAAMI .223 throat the the chamber pressure will be approximately 5,000 psi higher.

Now to add even more confusion, the throat in my Savage .223 with a 1 in 9 twist is longer than the throat in my AR15 rifles. Many of the rifle manufactures today are making the .223 chambers with a longer throat. This makes plenty of room in the chamber for the cartridge and the company lawyer and also lowers the chamber pressure.

Also note that military brass like Lake City is made harder in the base than any commercial .223 case. Meaning Lake City brass is the best brass the American tax payers can buy.

The 5.56 cases were made harder to help prevent the jamming problems the early M16 rifles had.

you know very few on all these AR forums would agree with the statements above. You are absolutely correct.

Glad to see your post!

 

[rcoody]

New to this round but not reloading in general. I know 5.56 is basically a 223 with a bit more pressure. I recently started shooting a mini 14 which I really like and would like to start reloading for it and make up several loads. one load for cheap plinking, another load for accuracy/hunting out to 300 yards and a third load for maybe house defense although I am not sure id want to be using a 223 for defense but who knows.

So first question, should I not even bother with 5.56 pressures and simply stick with 223 loadings (my mini 14 is stamped 5.56 on the receiver so it can handle it).
Second question, which bullets for coyotes out to 300 yards and last question is which rounds (if any at all) for home defense. Was thinking maybe V-max since they do not over penetrate. Any thoughts or things im missing?

I shoot a lot of .223 in ar's. Reload for my precision guns. Most of the reloading manuals only have the .223 loads. I believe my hornady manual is the only one I have that has 5.56 loading.

If you want your brass to last then use the .223 data. I do.

With a 5.56 or wilde chamber there is lots of room to go up. You just have to find what your rifle likes and what your uses are.

What is your twist. for coyotes out to 300 I would work on loads with the 69 or 77 gr. match king if you have a 1:8 twist. If a 1:12 I would look in the 52 to 55 grain sierra's. The hornady Amax is a good choice too but it might mess up the pelt.

 

[Bigeclipse]

I shoot a lot of .223 in ar's. Reload for my precision guns. Most of the reloading manuals only have the .223 loads. I believe my hornady manual is the only one I have that has 5.56 loading.

If you want your brass to last then use the .223 data. I do.

With a 5.56 or wilde chamber there is lots of room to go up. You just have to find what your rifle likes and what your uses are.

What is your twist. for coyotes out to 300 I would work on loads with the 69 or 77 gr. match king if you have a 1:8 twist. If a 1:12 I would look in the 52 to 55 grain sierra's. The hornady Amax is a good choice too but it might mess up the pelt.

I believe my mini 14 is a 1:9 twist

 

[bigedp51]

you know very few on all these AR forums would agree with the statements above. You are absolutely correct.

Glad to see your post!

I know I'm correct, I'm also very good looking, smart and exceedingly modest.

Below is the mil-spec requirement for commercially made 5.56 ammunition made for the military. Please note 3.7 chamber pressure is 55,000 psi using the American SAAMI traducer method.

Bottom line, 52,000 cup, 55,000 psi SAAMI and the European NATO CIP 62,000 psi are all one in the same chamber pressure.

Now look at line "N" throat length below for all the .223/5.56 reamers, it is the shorter .0250 throats that cause the pressure increase when firing M855 military ammunition. And the throat length for my off the shelf Savage .223 is 0.0566 and the longest throat is the Wylde at 0.0619.