Okay let me begin by saying I am very new to reloading and I know I still have a LOT to learn, but I’ve read that a rifle rated for 223 only cannot, or should not, be used to fire 5.56 ammo. In my case my rifle is a 5.56 so that is not an issue.
My question involves reloading for the pressures obtained when shooting 5.56 ammo compared to a 223. When looking at Lyman’s 50th anniversary handbook I see only how to reload for 223. I then referred to my Hornady Handbook which breaks down, not only, how to reload not only for 223, but a 223 Service Rifle and 5.56 too. My confusion arises when I compare Lyman’s manual to what I’m seeing in the Hornady’s manual.
For example, a 223 using a 75 gr. Jacketed A-Max and Varget powder the Lyman manual tells me the suggested starting weight of powder is 23.0 gr. with a maximum load of 25.6 gr.
Going to Hornady’s manual, under load data for 5.56 using the same bullet (75 gr. Jacketed A-Max) and powder (Varget) I see a starting weight of 21.8 gr and a maximum of 24.6 gr.
Which brings me to the crux of my question which, other than curiosity I really have no idea why I’m asking since it doesn’t effect me, but it really is nagging at me so I hope someone here can offer some insight. Obviously the data contained in the two manuals overlap so why wouldn’t the maximum load of 25.6 gr found in Lyman’s manual deliver pressures equal to 5.56 NATO? And wouldn’t someone using a rifle rated for 223 only experience potential problems?
My question involves reloading for the pressures obtained when shooting 5.56 ammo compared to a 223. When looking at Lyman’s 50th anniversary handbook I see only how to reload for 223. I then referred to my Hornady Handbook which breaks down, not only, how to reload not only for 223, but a 223 Service Rifle and 5.56 too. My confusion arises when I compare Lyman’s manual to what I’m seeing in the Hornady’s manual.
For example, a 223 using a 75 gr. Jacketed A-Max and Varget powder the Lyman manual tells me the suggested starting weight of powder is 23.0 gr. with a maximum load of 25.6 gr.
Going to Hornady’s manual, under load data for 5.56 using the same bullet (75 gr. Jacketed A-Max) and powder (Varget) I see a starting weight of 21.8 gr and a maximum of 24.6 gr.
Which brings me to the crux of my question which, other than curiosity I really have no idea why I’m asking since it doesn’t effect me, but it really is nagging at me so I hope someone here can offer some insight. Obviously the data contained in the two manuals overlap so why wouldn’t the maximum load of 25.6 gr found in Lyman’s manual deliver pressures equal to 5.56 NATO? And wouldn’t someone using a rifle rated for 223 only experience potential problems?
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