5.56 vs 223 Load Data

[DMW1116]

I’ve been looking at my Hornady and Ramshot load data and see the 5.56 data is considerably higher for the bullet weights I shoot. Is anyone running full 5.56 loads? I generally just stick with 223 since I’m not using these rifles for hunting. Both my rifles are 5.56 compatible and I thought I’d maybe push on up a little. Hornady shows nearly a grain higher in 5.56 for their 75 grain bullet with an astonishing 2900 fps listed from a 20” barrel. I’m shootings a 20” and sorta want to try it as long as accuracy doesn’t fall apart.

 

[AJC1]

If you need the extra umph for long range target or hunting then go for it. If it's just for kicks you will burn out your throat faster and generate more heat in longer strings of fire. Only you can determine if the ends justify the means. I run 80s hot in a bench gun but my rate of fire is slow. I used to shoot to 600 but am now limited to 300 so I will dial back to the lowest node I can.

 

[armoredman]

I do load to 5.56mm for some loads, because I can. I also don't do mag dumps any more - I usually only load 5 in the mag at a time.

 

[twarr1]

I can usually find a node in the lower 50-70% of the load range. Less wear, less powder.
Everybody's different

 

[ms6852]

I do not use Ramshot, instead I use RL15 on my rifle with a 20" barrel. I do use my AR for hunting occasionally and all I use are 75 grain Hornady BTHP bullets. In my rifle it is very accurate at 500 yards and sub moa at 200 yards 5 shot groups velocities average around 2510 fps. I would load yours to which ever gives you the best groups, I would not be surprised if it was most accurate at the lower velocities.

 

[DMW1116]

I suppose every reloaded has a phase where they like to see how fast they can push things. This might be mine. I have an accuracy load for 223 using the Hornady 75 grain bullets, but it’s for another rifle and doesn’t work as well out of this one. I have a load to test today with 77 grain SMK and CFE 223. The 5.56 data goes nearly a full grain higher than where I stopped, making the large assumption that data for a 77 grain and 75 grain projectile are basically the same, which may not be true. Ramshot publishes data for both and the velocity difference is significant. They use a 24” test barrel though.

 

[dgod]

I try to keep my 5.56 loads between 2800 and 2900 FPS, they seem more stable out of my LE/AR15.

 

[runner3264]

I load for a friend and his AR has a 20" barrel. I load H335 24.5gr and he is shooting 1/2" groups at 200 yards. These are 55 grainers. You can take it up to 25.3 which will give you 5.56 velocities. Also depends on your twist rate of the barrel will decide what weight bullets will shoot well with your rifle. Heavier bullets than 55gr will shoot better with a slower powder like Varget. Varget works great with 69gr and up as compared to the H335 which is great for 62gr and down

 

[DMW1116]

I have a H335 load I use for 200 yard shooting but it won’t do that. I guess I should say I won’t do that as the 20” rifle is equipped with a carry handle for peep sight use. There isn’t much chance I could see well enough for that.

I’m using an FN barrel on a PSA CHF kit. The twist is 1:7. So far I’ve not tried heavier than 55 grain bullets with it. I’ve tried TAC, H335, and CFE 223. The test batch is loaded up to the max of 223 specs of CFE 223 based on my Lyman reloading manual. I’ll see how they do and then maybe push up into the higher pressures based of the Hornady data if these don’t do well.

 

[irishlad]

I can usually find a node in the lower 50-70% of the load range. Less wear, less powder.
Everybody's different

That's what usually happens to me also. I rarely come close to max loads.

 

[Dale Alan]

That's what usually happens to me also. I rarely come close to max loads.

Same here , I almost always end up on the lower end .

 

[Bfh_auto]

I suppose every reloaded has a phase where they like to see how fast they can push things. This might be mine. I have an accuracy load for 223 using the Hornady 75 grain bullets, but it’s for another rifle and doesn’t work as well out of this one. I have a load to test today with 77 grain SMK and CFE 223. The 5.56 data goes nearly a full grain higher than where I stopped, making the large assumption that data for a 77 grain and 75 grain projectile are basically the same, which may not be true. Ramshot publishes data for both and the velocity difference is significant. They use a 24” test barrel though.

I'm curious how that works for you. My 5.56 guns seem to be the most finicky ones to load for.