450Bushmaster.net

Since a factory polymer magazine for the 450 isn't likely to be materializing anytime soon, I decided to make one. I tried modifying a PMAG, removing the central rib, but ended up destroying it in the process. Not wanting to try my hand at it a second time (mainly due to frustration levels) I searched for other options. I found the Lancer mags and was intrigued. Polymer mag but the benefit of metal feed lips. I ordered a 20 rounded from Brownells. I examined the inner mag profile and was able to 3D print and modify a copy of the common blue snap-in follower found on ebay to work. I wanted to do one better though and actually print a follower that would replace the factory 223 one and better match the inner mag profile. Attached are photos of what I came up with. With the factory spring it will hold 7 rounds, my guess is I can get one or two more by trimming the spring a coil or two. You'll notice that the rounds are staggered within the magazine but have no trouble feeding into the feed lips when emptied with my thumb. I did not put the magazine into a rifle yet to check how they feed when fired (ran out of daylight and Dad duties). I do need to sand down a few of the faces of the follower for a slightly looser fit though it does function well right now. I may also put a CA glue finish on it to ensure smooth surface contact (trick I use for 3D printed parts in my day job).

I'll report back after a firing test!

Good stuff!! Looks good , hope it works better. Look forward to your results

Very nice work and look like they are sitting at a perfect angle too. Is there a "U" notch in the front of those mags?

I'm a fortunate old soul, my 16" factory upper has ran with every mag/bullet combo I've tried with little to no tweaking sans dehorning which I do to every metal AR mag regardless of caliber.

Al in Mi wrote:Very nice work and look like they are sitting at a perfect angle too. Is there a "U" notch in the front of those mags?

I'm a fortunate old soul, my 16" factory upper has ran with every mag/bullet combo I've tried with little to no tweaking sans dehorning which I do to every metal AR mag regardless of caliber.

Thank you!

There is no half-moon cutout in these from the factory as they are designed for 223/556 use. I did however use a sanding drum on a dremel and replicated the half-moon cutout on my original Stoner bushmaster metal magazine in about two seconds.

I hopefully can provide a test fire update this weekend when I'll have some time to walk out back and touch a few off.

After some light 1000grit sanding the follower moves perfect in the magazine. I tested it today (sorry no pics as it's snowing out) but I was able to run 2 complete mags (14 total) rounds without issue and bolt held open on last each time. Super happy with this follower and ordering a few more Lancer mags soon!

that's great, save the program and model for that printer !!!

Al in Mi wrote:that's great, save the program and model for that printer !!!

Model is definitely saved, I have another print job tomorrow for several more

If you decide to offer these for sale, I'd likely be interested in a couple.

303hunter wrote:If you decide to offer these for sale, I'd likely be interested in a couple.

I've gotten a few requests but haven't had the time lately to really think about it...

If I had to hazard a guess at it right this second I would probably offer them for $8-12/pc, that would include the shipping.

rinkrat311 wrote:

303hunter wrote:If you decide to offer these for sale, I'd likely be interested in a couple.

I've gotten a few requests but haven't had the time lately to really think about it...

If I had to hazard a guess at it right this second I would probably offer them for $8-12/pc, that would include the shipping.

That sounds good. I’d rather my $$ go to a forum member than some guy on eBay.