Bigger Caliber on Standard AR15 lower

[L4D]

Current upper is 5.56
What larger caliber upper can I use with a multi-cal lower, are there any changes that need to be made to the FCG?

[mif_slim]

a quick "search" and you can find a bunch of calibers. But, for the sake of it you can go as big as 50 Bewolf. And for rifle case, anything smaller or shorter rather then .243 is gtg. Most will change the bolt only, some you'll have to change the entire bolt.

For starters:

22lr, 223/556, 9mm, 40sw, 45acp, 7.62x39, 300 blackout(my project in progress), 450, 500 beo, so many more that I cant think of right now..

[L4D]

a quick "search" and you can find a bunch of calibers. But, for the sake of it you can go as big as 50 Bewolf. And for rifle case, anything smaller or shorter rather then .243 is gtg. Most will change the bolt only, some you'll have to change the entire bolt.

For starters:

22lr, 223/556, 9mm, 40sw, 45acp, 7.62x39, 300 blackout(my project in progress), 450, 500 beo, so many more that I cant think of right now..

I like the idea of the 300 Blackout would that require a barrel and bolt change only?

[Lifeofahero]

Only a barrel change the 300blk uses a standard bolt.

[Mr.Caketown]

Ive never heard of the 300 BLK , what is the goal of this caliber? is it a miltary round ? a long distance rd?

[mif_slim]

I like the idea of the 300 Blackout would that require a barrel and bolt change only?

Yup, only barrel change. I only found two makers of that barrel though, Navoske and Black Hole Weaponary. I ordered the BHW so I'll let you know if its good or not.

[high_revs]

Current upper is 5.56
What larger caliber upper can I use with a multi-cal lower, are there any changes that need to be made to the FCG?

are you asking what other caliber uppers you can mate to your ar15 lower?

in addition to above... 6.8 & 6.5

[L4D]

are you asking what other caliber uppers you can mate to your ar15 lower?

in addition to above... 6.8 & 6.5

Yes, what other larger than 5.56 calibers can be mated to my multi-cal lower?

out of all of the available options what would be the chosen caliber for longest distance?

[joefreas]

50 DTC. No changes to FCG only a stronger hammer spring.
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[mif_slim]

Yes, what other larger than 5.56 calibers can be mated to my multi-cal lower?

out of all of the available options what would be the chosen caliber for longest distance?

6.5 would be my choice of long distance shooting.

[jrivera408]

6.8 spc ??? check out ssarmory.com if your a non believer.

Theres also 204 ruger I believe that will fit in the lower.

[dieselpower]

@ L4D, are you asking what is the largest that will magazine feed, or the largest that can be supported and fired by the same 556 lower?

[L4D]

@ L4D, are you asking what is the largest that will magazine feed, or the largest that can be supported and fired by the same 556 lower?

Largest that can be magazine fed is what im looking for.

but just for ****s n giggles whats the largest that can be supported and fired from the same lower?

[gun toting monkeyboy]

Largest that can be magazine fed is what im looking for.

but just for ****s n giggles whats the largest that can be supported and fired from the same lower?

50 BMG. They make bolt action uppers for ARs that can shoot 50 BMG, or it's California legal clone. And just for the record, it doesn't matter what is engraved on your receiver. It can say "Multi", "5.56" or "Martian Death Ray" on it, and you can change the caliber til your heart's content. There are no legal reasons not to.

[jokat989]

"Martian Death Ray"

where can i find this lol