Yes, quite a bit. The 855 is a 62gr lead core jacketed projectile with a steel penetrator. The BC is a little low and doesn’t create much yaw.
855A1 uses a 62gr solid copper projectile pulled up on a harder exposed penetrator. These have a pretty high BC and outperform 855 by a bit. They also use a flash retardant powder, but the exit velocity is about the same. Solid copper almost always moves faster and has higher BCs. The they shoot extremely flat compared to 855 and have about twice the barrier penetration. The two-piece construction is designed to create yaw when they hit a target and maximize lethality.
There are some good articles on the web...this one from 2010 was a little premature in that LTC Woods says the ballistics are the same and a few months later they were trying to figure out how to accommodate the flatter trajectory without changing the reticle in 10s of 1000s of ACOGs.
Perhaps no subject is closer to the hearts of Soldiers than their weapons and ammunition. For decades, this intense interest in
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Anyway, this is what one looks like...the resin's turning yellow tho.
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