I also don't believe ammo is regulated. Got this on-line

SUMMARY

Neither state nor federal law prohibits online ammunition sales or purchases. Several companies currently sell ammunition online.

Some companies post eligibility criteria for, and restrictions on, online ammunition purchases; others do not. Typically, those that post this information require purchasers to meet federal criteria for purchasing ammunition, which are the same as for firearm purchases. They require buyers to submit proof of age and “affirm” or “confirm” that they meet the criteria. The websites do not specify any other steps, if any, the companies take to verify that buyers are eligible.

STATE AND FEDERAL PROHIBITION ON ONLINE AMMUNITION SALES

Connecticut does not regulate ammunition sales, except to the extent that it prohibits anyone from knowingly distributing, transporting, importing into the state, keeping, offering, or exposing for sale, or giving anyone any “armor-piercing .50 caliber bullet” or “incendiary .50 caliber bullet” (CGS § 53-202l(b)). And while federal law bans online firearm transactions, it does not regulate online ammunition sales. Federal law governing ammunition is limited to (1) prohibiting sales to and purchases by certain categories of people (e.g., felons, illegal aliens, and illegal drug users) and (2) prohibiting the manufacture, importation, and sale, by any means, of armor-piercing ammunition. It requires a person to be at least age 18 to buy long gun (shot gun or rifle) ammunition and at least age 21 to buy handgun (pistol or revolver) ammunition. But if a state law or local ordinance sets a higher minimum age, the higher minimum applies (18 USC § 922(b)(1), 27 CFR § 478.99(b)).