It all depends on what you’re doing. If Shooting factory ammo with no reloading that brass it won’t matter. Even if you’re planning on reloading just buy from someone like Patriot Valley, Red Beard Gunworks or hell even from me. Just someone that sells AI barrels and knows what they need. Most all guns I’ve had go through the shop are all damn near similar. I had one that was out of spec, it was .004” to long in the action, I’d guess from Shooting it ALOT.
All in all it’s only been an issue with 1 barrel and that 1 rifle, I brought the rifle in, checked everything and it was the action. Trust the place you’re buying from and you’ll be fine.
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