The XM1158 ADVAP is based on the design of the M80A1 EPR, but features a tungsten - rather than steel - penetrator. Seen here are eight rounds of M80A1 clipped together with a little bit of anachronism.

A key part of the capability brought to the table by the US Army’s new Squad Designated Marksman Rifle is its chambering for the 7.62mm round. Specifically, this chambering allows the SDMR to fire the (also brand new) XM1158 Advanced Armor Piercing (ADVAP) round, designed to give the squad the capability to defeat advanced ceramic armors at combat ranges. There may be juuuuust one little problem, though: Cost. The US Army’s Ammunition Budget Justification for Fiscal Year 2019 was released this month; in it was procurement information on the XM1158 ADVAP, and a bit of a shocking sticker price to boot:

This is of course the first year that the ADVAP will enter major production, so it is possible this high price is the byproduct of the economy of scale. Comparing this figure to the same figures in the FY 2013 Budget Estimate for M855A1, and considering that more than a million rounds of ADVAP are being ordered, however, that doesn’t seem to be the case:

By 2018, according to the 2019 Justification, the cost for the M855A1 had dropped considerably, to just $0.36 per round ($0.31-$0.40 depending on the packaging):

Although this represents a cost reduction of 53% versus the introductory cost, it still doesn’t bode well for the ADVAP: If the reduction is applied the same way, the ADVAP will still cost the Army more than six dollars a round.

It’s also worth considering that the XM1158 ADVAP is not a steel-cored 5.56mm round, like M855A1, but a tungsten-cored 7.62mm round. Tungsten will naturally be more expensive, but how much more should we expect this round to cost? For that we turn the FY2018 US Air Force Budget Estimation Justification Book:

Even in relatively small quantities, the 7.62mm M993 Armor Piercing still costs just $2.9/round. Even if the cost of M1158 ADVAP falls by 53% over its lifetime, it will still be more than twice as expensive as the existing armor piercing round. For a round that is supposed to be both more capable and cheaper to produce than the existing tungsten-cored AP round, this is somewhat concerning.

Having said all that, it’s possible the price tag of the XM1158 ADVAP will fall sharply by fiscal years 2020 and 2021. It was hinted in the Picatinny Voice article about the round that a new production method was developed to make the ADVAP cost effective. It is conceivable that this $13 per round price tag reflects startup costs for new machines and tools.

Besides the surprising price tag, the budget justification also confirmed that the ADVAP round will be a variant of the bullet design pioneered with the M855A1 EPR round, stating in the description for item that:

The M1158 Ball Cartridge utilizes projectile with an exposed black metal tip surrounded by a copper jacket. The M62A1 Tracer Cartridge also contains a lead free projectile and provides a visible red light signature through its trajectory and is a ballistic match with the M1158 trajectory. They are intended for use against a broad spectrum of hard targets. … This is a war reserve item used in combat. The FY 2019 request builds a war reserve inventory in accordance with the Army’s procurement goals. FY 2019 Base procurement in the amount of $25.000 million supports the procurement of 1.675 million 7.62mm M1158 Advanced Armor-Piercing (ADVAP) Ball Cartridges 4Ball/1 M62A1 Tracer linked Cartridges.

It is interesting that, despite the M1158 ADVAP reportedly being intended for use in the magazine-fed the Squad Designated Marksman Rifle, the round does not appear in clipped form anywhere in the FY2019 Budget Justification, only linked with M62A1 Tracer for the M240 Machine Gun.

Thanks to Ramlaen for the tip!