More m16 questions....

mrnkc130

New member
What calibers can I use with a regular milspec lower just changing magazine and complete upper?

I know 6.8spc (anyone have one? how do you like it?)

22lr (with or without dedicated upper)

5.7x28 with FN type magazine on top is all I have seen for this...

I found all these on DPMS but not sure which of them will work without a dedicated lower for that caliber.

.204 Ruger
.223 Remington
5.56x45mm
6.8mm Remington SPC
7.62x39mm
.243 Winchester
.260 Remington
.338 Federal
6.5 Creedmoor
.458 socom

Also most important question: is it legal to put what ever caliber upper I want on a m16 FA lower? Or do you have to stay with 5.56? Which calibers are compatible with FA m16 lower as opposed to SA(if legal to do so)?

I have the feeling it's just too good to be true that you could by a m16 FA and drop whatever upper in different calibers you want on it...
 
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I have the feeling it's just too good to be true that you could by a m16 FA and drop whatever upper in different calibers you want on it...

You'd be surprised to learn, then, that this is why IMHO the M16 is THE machinegun to own. I bought mine for exactly this reason. I have shot it in lots of calibers including 5.56mm, 9mm, .22lr, 5.45x39.... I don't know that I'd want to try shooting it in Auto with some of the calibers you listed but hey, it's your gun...
 
How about auto bolt carriers for all the other calibers? main interest would be in 6.8, .22, 9mm (how do mags fit in .223 reciever?) and maybe 7.62x39..
 
Most calibers use the same bolt carrier, just a different bolt.

9mm uses a mag well adapter either welded to each mag or temporarily inserted into the mag well. You will probably change the hammer and bolt too. 5.56 hammer is to short.

If you shoot a lot of .22 in a m16, clean the gun very well when you are done. There have been some kabooms linked to 22 gunk in the 16.

7.62x39 can be finicky on feeding due to the shape of mags. google m16 frankenmags and c-products. Some folks are lucky with them, some aren't.
 
9mm mags will require a mag block conversion. These simply drop-in and are easy to use. .22lr mags require no modification and insert into the magwell just like standard mags. I run a dedicated upper for my rimfire setup so no worries about fouling up a .223 upper. 1200rpm of .22lr is just full of WIN!
 
What calibers can I use with a regular milspec lower just changing magazine and complete upper?

You forgot the .50 BMG.

CammoGunLRG2.jpg
 
Thanks for all the replies everyone much appreciated! definitely think m16 is the way to go with all the options. Expensive but you bascially get several machines guns for the (over)price of one!
 
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