What’s the difference in this ammunition?

[Nuclear Worker]

I have been using the blue box ammo. Which is GB542 OTM scenar l. Have a chance to get 20 boxes of the red box which is GB 478 HPBT. The red box ammunition is older I believe. Can anyone explain the difference and will it matter?

 

[spike-55]

the red box has the old "gold box" brass and likely has a different bullet. but those old red box's were known to shoot sub 1/2 and 1/4 or better in lots of rifles.
stan