New 300 BO PMAGS

[Steelin' Ducks]

I thought one of the selling points was that it used standard 5.56 mags?

https://www.magpul.com/products/pmag...gen-m3-300-blk

[Griffin]

They do.

[Steelin' Ducks]

I know. That's my point

[Griffin]

A sucker is born every day. I like how they added the poptental to chamber and fire a 300bo in a 5.56. Not even physically possible

[FLS]

I've seen 2 rifles blown up because a mag of BO got put in a 556 one was a very expensive SBR. Both times it was after a mag change. I think the momentum of the bolt forced the bullet deep enough in the case for the round to chamber and fire. Both were catastrophic. It an individual's responsibly to keep the right ammo in the right gun, but a dedicated mag doesn't seem like a bad idea.

[Griffin]

I've seen 2 rifles blown up because a mag of BO got put in a 556 one was a very expensive SBR. Both times it was after a mag change. I think the momentum of the bolt forced the bullet deep enough in the case for the round to chamber and fire. Both were catastrophic. It an individual's responsibly to keep the right ammo in the right gun, but a dedicated mag doesn't seem like a bad idea.

I'm not even sure how that works. I'm guessing the projectile goes back case but what does the case neck do? How does it neck down with a 30cal projectile between case walls? again it doesn't seem possible given the chamber dimensions on both

[ecu1984]

I'm not even sure how that works. I'm guessing the projectile goes back case but what does the case neck do? How does it neck down with a 30cal projectile between case walls? again it doesn't seem possible given the chamber dimensions on both

what he said, I have a 300 and a 556 and couldn't put a 300 into a 556 chamber

[Griffin]

I just tried it. Not even close

[walt4dun]

I've seen 2 rifles blown up because a mag of BO got put in a 556 one was a very expensive SBR. Both times it was after a mag change. I think the momentum of the bolt forced the bullet deep enough in the case for the round to chamber and fire. Both were catastrophic. It an individual's responsibly to keep the right ammo in the right gun, but a dedicated mag doesn't seem like a bad idea.

I put a wrap of tape on my mags loaded with 300BO for that reason.
Same with mags of tracer.

[Coastal Woodie]

I tried to get a 300 to chamber into a 5.56 and it won't even come close to fitting. Nevertheless I wrote 300 on several mags so I don't mix them up.

[FLS]

It will chamber if the gun is cycling after being fired. There is enough force to do it. Watched happen twice. Bullet it being pushed back in case and 300 shoulder and neck is short enough to chamber. I was ROing one and waiting to shoot the second time. Take an empty BO case and cycle it from 556 mag into 556 chamber. It fits, BO case neck doesn't even reach 556 shoulder/ neck junction. Bullet gets set back and KABOOM.

[Griffin]

It will chamber if the gun is cycling after being fired. There is enough force to do it. Watched happen twice. Bullet it being pushed back in case and 300 shoulder and neck is short enough to chamber. I was ROing one and waiting to shoot the second time. Take an empty BO case and cycle it from 556 mag into 556 chamber. It fits, BO case neck doesn't even reach 556 shoulder/ neck junction. Bullet gets set back and KABOOM.

Also tried this this morning and it still won't even think about chambering a the round. I intentionally loaded a 300bo round second and it's a no go. Not saying you haven't seen it but it doesn't work on my shit. for that matter I have 300bo rounds that are for a bolt gun with a longer OAL and those won't chamber. iE it won't move the projectile back in the case.