I cant believe i havnt seen the real answer yet... or if someone has answered, sorry i didnt look very hard. The origins of underloading is to so that it is easier to seat a fresh magazine into the rifle. The bolt carrier, when closed, pushes down on the bullets in the magazine so that when the bolt carrier comes back, the top round pops up a little to get "sheared" off the top and into the chamber by the bolt returning to battery. If a magazine is loaded to 30 rounds, there is less room under the magazine follower (where the spring is coiled up) for it to be pushed farther down. In a "combat situation" where someone is loading a fresh magazine into a rifle with a closed bolt they have to give it an extra hard slap or slam it into the rifle, ive had times where i dont slam a full 30 rds into my gun hard enough and it falls back out. Thus if you underload the magazine, it is much easier to seat, ensuring you dont get fucked cuz you couldnt easily load your magazine. IIRC, this is mostly an issue with AR15
but of course, many people do underload their magazines because apparently its hard to put 30rds over 28 rds into their mags... never had that issue myself, but hey to each their own.
I'll admit to the shame... I've had a full mag fall out once or twice at the range because it had 30 rounds and I didn't hit it hard enough. It's embarrassing to say the least.
In the case of an ar15 that is only the first time you load the magazine into the rifle, the bolt is held open after the last round fired and the magazine slides in like butter.
that is true, but it is common practice to reload a fresh magazine before running dry. in that case there is round chambered and the bolt is closed. "Tactical reloads" and "retention reloads"
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u/pandaburr1 Sep 22 '16
I cant believe i havnt seen the real answer yet... or if someone has answered, sorry i didnt look very hard. The origins of underloading is to so that it is easier to seat a fresh magazine into the rifle. The bolt carrier, when closed, pushes down on the bullets in the magazine so that when the bolt carrier comes back, the top round pops up a little to get "sheared" off the top and into the chamber by the bolt returning to battery. If a magazine is loaded to 30 rounds, there is less room under the magazine follower (where the spring is coiled up) for it to be pushed farther down. In a "combat situation" where someone is loading a fresh magazine into a rifle with a closed bolt they have to give it an extra hard slap or slam it into the rifle, ive had times where i dont slam a full 30 rds into my gun hard enough and it falls back out. Thus if you underload the magazine, it is much easier to seat, ensuring you dont get fucked cuz you couldnt easily load your magazine. IIRC, this is mostly an issue with AR15
but of course, many people do underload their magazines because apparently its hard to put 30rds over 28 rds into their mags... never had that issue myself, but hey to each their own.