Newbie questions

[sva01]

Hi guys,
New here and to the 450 caliber. I have a desire to learn more and am hoping you'll be willing to tell me what I don't know.
I plan to buy an upper for use on an existing lower. I think I have that part figured out
My main curiosity is concerning magazines for these rounds. I see the "black follower" thread and am curious if I'll want these as well or are the current factory mags working well? How do I modify my existing GI mags to work with 450? Does the mag spring need to be changed or just the follower? I see this follower on ebay: http://www.ebay.com/itm/Magazine-Follow ... 2584ceebeb and am curious if they are good to go or if I need to try to find the black followers that are referenced on the board?
I appreciate the help and am looking forward to using this caliber here in West Michigan!

[Al in Mi]

Pretty sure all the new BM mags have black followers, last couple 5rd I got did anyways.

I have a couple I did up with those blue followers in 20rd C Products mags and had to "roll the feed lips" in a little to keep the nose of rounds down, but they worked fine too. Use the same spring, that blue follower just sits on top of the existing follower.

welcome aboard

[helidude350]

Howdy, and welcome aboard.

If your factory mags work, you are good to go!
If you see some deep scratches on your brass, polish the feed lips with sand paper or scotchbrite a bit.

If you have some issues, there is plenty on here to help.

The black follower is really just for the last round to line up.

I have two 450bushys and a variety of mags.
The uppers work flawlessly.
The only problems have been a few mags. But that can be said for any mag fed pistol or rifle.
I've used factory 450 mags, modified mags, unmodified 223/556 mags with varied results.
Plenty on here have had no problems with 223/556 unmodified mags and so have I.

So shoot and enjoy!!

[helidude350]

I bought some of those blue things.
tweaked on one.
was just a hassle.
never shot with it.

they're just in a box somewhere.

But that's just my experience with them.

[sva01]

If I'm understanding you correctly, I may be able to use GI mags with the 5.56 followers and no modifications? I've got lots of those and don't really want to buy the $35 factory 450 mags if not necessary. I didn't realize that was a viable option...
Obviously the last round will probably fail to chamber properly if not using a 450 follower but the ones above that should be OK?
I ordered my upper yesterday and am looking forward to receiving it next week!

[ardenkent]

the magazine issue is not really the follower but the width of the magazine mouth.
the 223 is a double stack, the 450 is a single stack, yet a 450 cartridge may not be
held captive in the GI mag.
so you may have to narrow the gi mag mouth, by bending the feed lips inward
then polish the lips to minimize the brass wear and after all that effort the final
cartridge may still fail to feed.
save the trouble, buy the official from the factory extra mags !

[Avenger10]

Over at BartZ Manufacturing we will have some B.. A.. magazines in about two weeks. We are stamping bottom plates right now then off to plating and we are good to go. They are 5 round capacity standard straight body mags and they work flawlessly. We test 100% of our mags before they go out the door and we keep the price under $30.00.

Thanks,

-Barttman

[Jim in Houston]

the magazine issue is not really the follower but the width of the magazine mouth.
the 223 is a double stack, the 450 is a single stack, yet a 450 cartridge may not be
held captive in the GI mag.
so you may have to narrow the gi mag mouth, by bending the feed lips inward
then polish the lips to minimize the brass wear and after all that effort the final
cartridge may still fail to feed.
save the trouble, buy the official from the factory extra mags !

If you have some GI mags, try them out. Yes, the .223 / 5.56 double stack in the mag, but they single stack on the feed lips, the same as the 450 BM. I have never had a problem shooting standard AR mags, especially the straight, 20 round ones, including chambering the last round. However, the 30 round curved mags may not feed properly, as the 450 BM round won't always go around the curve.

The same goes for the standard follower with the .223 / 5.56 shape at the bottom. My experience is that it will push the last 450 BM round up against the lips.

[Avenger10]

If you have some GI mags, try them out. Yes, the .223 / 5.56 double stack in the mag, but they single stack on the feed lips, the same as the 450 BM....

I have to disagree with Jim a little bit. The .223 / 5.56 mag does double stack but it does not single stack at the feed lips like the 450b. 5.56 rounds ride under the feed lips until they strip, alternating between the left and right lip. That's why feed ramps are cut one left and one right. Rounds do not center between them like the 450b. The 450b has one centered feed ramp.

I do completely agree with Jim with respect to the straight -vs- curved mags. The straight ones work and the curved ones just don't. Midwayusa kinda lost their butt when they tried to sell the 9 shot curved mag under their ARStoner banner.

Our mags are all made from 20 round straight bodies and they work flawlessly.

-Barttman

[Jim in Houston]

If you have some GI mags, try them out. Yes, the .223 / 5.56 double stack in the mag, but they single stack on the feed lips, the same as the 450 BM....

I have to disagree with Jim a little bit. The .223 / 5.56 mag does double stack but it does not single stack at the feed lips like the 450b. 5.56 rounds ride under the feed lips until they strip, alternating between the left and right lip. That's why feed ramps are cut one left and one right. Rounds do not center between them like the 450b. The 450b has one centered feed ramp.

I do completely agree with Jim with respect to the straight -vs- curved mags. The straight ones work and the curved ones just don't. Midwayusa kinda lost their butt when they tried to sell the 9 shot curved mag under their ARStoner banner.

Our mags are all made from 20 round straight bodies and they work flawlessly.

-Barttman

Yep, my bad. The GI mags do double stack the rounds up to the feed lips. Doesn't seem to affect the BM450 feeding though.