If you use W748 or AA2520 for .233 come in.

There are countless reloaders who use W748 for the .223/5.56mm with good success. That powder along with BL-C(2) is usually more associated with the other NATO round but it will work just fine with the .223 too.

Western Powders shows AA2520 as a little slower than W748 and Hodgdon shows W748 as a little slower than AA2520 so for the most part they are in the same burn rate range so if you're happy with AA2520 you will probably be happy with W748.

I have a buddy wh has been reloading since lead bullets were your only option and he uses nothing but W748 for his .223 ammo and he's very happy. I use a similar powder in H335 but IMO there's nothing wrong with W748 either.

Before you run out of AA2520 load up a test between the 2 powders. Use the same brass trimmed to the same length. Use the same exact bullets seated to the same length and see how well each powder does against the other.

The W748 will be easier on the barrel. It does a very good job in my bolt guns. Will try some in my AR'S next summer.

748 works great for me but I've only tried it with 55 grainers.

I've used 748 with 69g projectiles in .223 Rem in an older Mini-14 years ago.

I saw good things happening for accuracy, but the barrel heating/point of impact walking with the Mini-14 was a real pain. Ruger has since changed how barrels are made for that rifle, so current production units should be much better.

Remember that ball/spherical powders are a little fussy about temperatures, so develop max loadings during your warmest weather you plan on shooting them in.

I run 69s through my ar with 2520 and don't see any issue. Never tried the win. Think I run 24.6 of the AA

Have not ever shot any of the 2520, don't think I've ever seen it on dealers shelves.
Howsomever tho I have shot many many pounds of 748 thru the 223 and a couple or 3 other cartridges.. It's good stuff delivers good accuracy and velocity. Any powder will heat up a barrel if you grip and rip, any powder will heat a barrel with a minor rapid fire. The thing to keep in mind is a sensible rate of fire, not get the barrel to hot, and keep it clean.

I tried 748 a while back and couldn't get as good as groups as 2520 for 68/69 grain (~25gns in a LC case). Its also very good in 7.62 with a 168.

I love using Win 748. I use it for my daughters practice plinking round, under 55gr FMJ. They're great for her to plink with.

One of my pet loads is 748 with a 68g HPBT.