NATO member Bulgaria is a Balkan country with a Black Sea coast and a population of six million. Bulgaria has made significant contributions of weapons to Ukraine. Initially this included sending all its Soviet-era Russian weapons and munitions to Ukraine, which also had weapons that used Russian munitions. At the same time, Bulgarian arms factories began working round-the-clock to produce older Russian-caliber munitions while adding production facilities for NATO standard weapons and munitions. Ukraine still has a lot of Russian weapons, like 152mm howitzers but is receiving more and more NATO standard 155mm guns and 155mm ammunition. Ukrainian weapons needs will eventually be just for NATO standard munitions. During the transition Bulgaria will be producing both types of munitions.
Even before joining NATO in 2004, Bulgaria was a major, for its size, munitions manufacturer. Since then, Bulgaria has continued to be a major producer and is obtaining loans from the European Union (EU) to increase production. Nearly all Bulgarian munitions are going to Ukraine and that will continue until the Russians are gone. After that Bulgaria will become an exporter of NATO-standard munitions. That market will be robust for a while because so many nations have sent most of their munitions stockpiles to Ukraine and need to replenish their war reserves. These are stockpiles of munitions to supply the troops until local production or outside sources can be found to keep the munitions coming. NATO nations have depleted their stockpiles to supply Ukraine.
The Ukraine War is the first near-peer war since World War II. Near-peer means both sides have roughly equal weapons and munitions supplies. It was quickly rediscovered that when it comes to munitions supplies, quantity is a key factor. Both Russia and Ukraine are aware of this and strive to have more artillery munitions than the other side in key battles. As a result, both sides are desperately seeking more sources for 152mm (Russian) or 155mm (Ukrainian) shells.
So far, for both sides, this is a case of too much is not enough. A major constraint on ammunition supplies is cost. NATO nations are now facing major military, economic and security problems. What it comes down to is that military leaders back all possible military aid for Ukraine while political leaders face problems with paying for it. Not just the financial cost, but the impact on voters who find themselves facing higher taxes and as well as inflation and shortages of essential goods. Supporting the Ukrainian war with Russia is expensive and exposes the true costs of cutting defense expenditures in the past by not maintaining sufficient stockpiles of weapons and munitions.
The basic problem is that it is a historical fact, reinforced by what happened in Ukraine, that you must maintain adequate stockpiles of ammunition and equipment for use against a large, well-equipped force in a war. These stockpiles are also referred to as the War Reserve, large quantities of munitions and spares stockpiled to keep the troops supplied during the initial 30-60 days of fighting until production can be increased to sustain the fighting. These stockpiles must contain the most useful munitions and other supplies and be positioned so they can be moved to the combat zones as quickly as possible. Without adequate logistics, as in the right supplies delivered in time, wars or at least battles, are often lost early and often. This is happening to the Russians and is crippling Ukrainian war efforts because NATO cannot keep key weapons and other supplies coming.
NATO military leaders point out that supporting Ukraine is not just about supporting a nation facing conquest and annexation by Russia. The real issue is that Russia will attack NATO members next if it wins. They can see what that would mean from what is happening in Ukraine. If Ukraine hand been a NATO member when the Russians attacked, the Russians would face NATO troops from all NATO members. That would mean all NATO members would be suffering troop losses, Russian missile attacks, etc., and that motivates voters to support paying the high economic costs of defending Ukraine. Russia sees victory in Ukraine as a victory over NATO and a weakening of NATO resolve to comply with mutual defense aspects of membership. Russian victory in Ukraine would make the new, since the 1990s, NATO members vulnerable to attack and annexation by Russia before other NATO members could help prevent it. For NATO nations adjacent to Russia, these fears aren’t theoretical but historical and often include centuries of Russian aggression and brutal occupation that sometimes led to annexation. A key antidote for Russian aggression is to have more ammunition and access to larger suppliers. This means obtaining more ammunition than peacetime governments and voters want to pay for. It’s either pay or pray your opponent runs out of ammunition before you do.