What calibers can I use with my lower

[Busch Lite]

I have a Franklin Arms lower that's stamped as multi caliber. I originally bought it for a 5.56 build. I'm not completely ignorant when it comes to the AR platform but definitely not an expert either. Can anyone give me some insight into what uppers I could use safely with this particular lower without any modifications? Any help would be appreciated. Thanks

 

[nitrousfedlx]

Without mods, 6.8 spc, 7.62x39, 300 blackout to name a few. For those calibers it's all in the uppers and magazines.

 

[cmshoot]

The list is a very long one. The common calibers are:

-.223/5.56
-.300 Blackout
-.22LR
-7.62x39mm
-.450 Bushmaster
-.50 Beowulf
-6.5 Grendel
-6mm ARC
-6.8SPC
-.224 Valkyrie
-9mm
-.40S&W
-.357SIG
-10mm
-.45 ACP

When you start looking at such things as single-shot bolt action uppers, you can go up to .50BMG and 20mm.

 

[Busch Lite]

I have a Franklin Arms lower that's stamped as multi caliber. I originally bought it for a 5.56 build. I'm not completely ignorant when it comes to the AR platform but definitely not an expert either. Can anyone give me some insight into what uppers I could use safely with this particular lower without any modifications? Any help would be appreciated. Thanks

 

[David's Gun Room]

5.56/.300blackout/6mm arc/6.8spc/.224valkyrie/.50beowulf/.450bushmaster/.458socom/.350legend etc in an ar15 reciever. Tons of cartridges

 

[BIKER13]

I think 350 Legend will work with correct magazines

 

[Jarebearlaflare]

5.56, 300BLK and 350 legend use the same BCG…most of the time it’s just a BCG, barrel and mag change…this is why the AR15 platform is so popular

 

[Omega]

You can do bolt fed 50 BMG upper on it, too. If you're feeling saucy

 

[C'mon man!]

Also, 9mm with endomags or one of those magwell contraptions. And don’t forget 22lr as well.

 

[Red Dawn]

6.5Grendel as well