Who to believe?

[rbahri5206]

I was doing some load work up on some 69gn .223 and I loaded according to my Lyman 49th edition and it said to load Imr-4064 min 22.9gn-25.5gn max but on line (imr website) it says 22.5gn min-24.0C. Now if that is a typo in the manual that is a dangerous one, at 24.0gn you are already compressed, now throw another 1.5 grains and compress it, that's kind of scary. What give's? should I not use the manual for load data and just go online? I know people swear by this manual that's why I bought it.

[Fjold]

Both are right for the components and the test barrel that the loads were developed in.

Reloading guides are just that, guides. You start at the recommended starting loads and work up to the maximum load that they recommend or that you develop in your gun.

[LynnJr]

Are the C.O.A.L. the same from both sources?
I would guess the Lyman manual uses a longer C.O.A.L.

[rbahri5206]

Are the C.O.A.L. the same from both sources?
I would guess the Lyman manual uses a longer C.O.A.L.

Lyman says 2.260" online says 2.235"

[bigedp51]

You case capacity governs how much powder your case will hold, one site used one brand of cartridge case and Lyman used another brand of case. This is "WHY" you start low and work up looking for signs of pressure.

Another thing is the type rifle you are loading for and a AR15 with a longer throat will have lower chamber pressures than SAAMI .223 loading data.





Below is the estimated chamber pressure of a .223/5.56 case with the "LEAST" amount of case capacity.



Below is the exact same load in a case with the "MOST" case capacity and "LESS" chamber pressure.



Reloading data is nothing more than "guidelines" to use "BUT" its up to you to remember each firearm will generate different chamber pressures along with the cartridge case and bullet used. Start low and work up and learn to read your primers and measure the base of the case for excess expansion.

If the base of your case looks like the one below you put too much powder in the case and need to think about using "LESS" powder. (and make sure your life insurance is paid up)



Reloading is like playing Black Jack, stay light and beat the pressure dealer.

[rbahri5206]

You case capacity governs how much powder your case will hold, one site used one brand of cartridge case and Lyman used another brand of case. This is "WHY" you start low and work up looking for signs of pressure.

Another thing is the type rifle you are loading for and a AR15 with a longer throat will have lower chamber pressures than SAAMI .223 loading data.





Below is the estimated chamber pressure of a .223/5.56 case with the "LEAST" amount of case capacity.



Below is the exact same load in a case with the "MOST" case capacity and "LESS" chamber pressure.



Reloading data is nothing more than "guidelines" to use "BUT" its up to you to remember each firearm will generate different chamber pressures along with the cartridge case and bullet used. Start low and work up and learn to read your primers and measure the base of the case for excess expansion.

If the base of your case looks like the one below you put too much powder in the case and need to think about using "LESS" powder. (and make sure your life insurance is paid up)



Reloading is like playing Black Jack, stay light and beat the pressure dealer.

Great information thank you for such a great write up.

[JagerDog]

Good info above and a good reason to sort cases.

Compressing powder really isn't a big deal from a safety standpoint.

[rbahri5206]

Good info above and a good reason to sort cases.

Compressing powder really isn't a big deal from a safety standpoint.

If it's not a safety concern to compress powder, how doesn't affect a load?

[Loubot10]

You case capacity governs how much powder your case will hold, one site used one brand of cartridge case and Lyman used another brand of case. This is "WHY" you start low and work up looking for signs of pressure.

Another thing is the type rifle you are loading for and a AR15 with a longer throat will have lower chamber pressures than SAAMI .223 loading data.





Below is the estimated chamber pressure of a .223/5.56 case with the "LEAST" amount of case capacity.



Below is the exact same load in a case with the "MOST" case capacity and "LESS" chamber pressure.



Reloading data is nothing more than "guidelines" to use "BUT" its up to you to remember each firearm will generate different chamber pressures along with the cartridge case and bullet used. Start low and work up and learn to read your primers and measure the base of the case for excess expansion.

If the base of your case looks like the one below you put too much powder in the case and need to think about using "LESS" powder. (and make sure your life insurance is paid up)



Reloading is like playing Black Jack, stay light and beat the pressure dealer.

Tag

[JagerDog]

If it's not a safety concern to compress powder, how doesn't affect a load?

I don't understand your question.

You aren't gonna set powder off by compressing it.

You aren't going to achieve some mythical chamber pressure upon firing a compressed load.

Handling during the reloading operation can become a pain at some point.

[rbahri5206]

I don't understand your question.

You aren't gonna set powder off by compressing it.

You aren't going to achieve some mythical chamber pressure upon firing a compressed load.

Handling during the reloading operation can become a pain at some point.

That's what I was concerned about, weather or not it would make more pressure.

[Pete1979]

Compressing wont hurt anything but I wouldn't expect you would gain anything as far as accuracy. A standard highpower load is 24gr of Varget or RL-15 or N140 under a 69 or 77gr Matchking. As you seat the bullet, you can hear and feel the powder crunching and all of the above mentioned powders have a much shorter grain size than 4064.
Stick with 24 and shoot.


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[LynnJr]

Lyman says 2.260" online says 2.235"

Here is your answer.
22 caliber centerfire rifles generally shoot best with the bullet into the lands or 0.018 - 0.023 off of the lands.
As you won't find any reloading data with a bullet seated into the lands the difference you posted above means one chamber is longer than the other.If you have alot of freebore you can use more powder because your pressure vessel(the case) has more volume and visa versa.

[Spyder]

Tagged for awesome info