The biggest obstacle to gun control in the US isn't the second amendment in that ignored archaic bit of 18th century scrap; but the number of people who own guns. Every new person who becomes a gunowner grows the problem.
Many people who became gunowners started by gingerly buying some $500 pistol and sticking it in a closet. This is how those new shooters you're taking to the range may start out. Any burden that creates a "barrier to entry" persuades these people to go find some other hobby.
This is fundamentally what people like Brit prime ministers refer to as putting tough restrictions on to head off there being a "gun culture", a critical mass of people strong enough to resist gun laws - by getting the gun laws out there early enough to prevent the problem.
Gun nuts overlook this as their 10 AR15s are in a foundation-cracking safe that's worth about 5% of the cost of their collection. But anything that can add to the "barrier to entry" for new people getting into guns has a higher ultimate impact than a mag or "assault weapon" ban.