This is their response. Are they saying that the 77gr smk is plated and the acceptable tolerances are 2-3gr from Sierra?
John,
Sorry for the delayed response. Typically, a plated projectile will be 2-3 grains different than what they advertise. These were made by Federal and advertised in their ammo as 77gr projectiles. Being a plated projectile made cheaper than an FMJ they tend to have lower tolerances for the final product. Differences usually come from the thickness of the electro-plating or extra lead at the end of the projectile. They don't have those issues with FMJ because the Jacket is pre made and causes the lead to form to it.
Hope this helps.
Thanks for your business!
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