AR Upper Question

[GunnyHwy]

Current rifle 5.56 AR. If I wanted a 6.8 cal upper can I just swap the upper and bolt or would I need a different hammer too?

 

[Chris L]

Should only need a 6.8 upper and bolt (don't forget magazines). Nothing in the lower is 6.8 specific.

 

[weeman]

I'm pretty sure the magazines are the same also just less capacity.

 

[clandestine]

Current rifle 5.56 AR. If I wanted a 6.8 cal upper can I just swap the upper and bolt or would I need a different hammer too?

Mags, Bolt Head and barrel are all thats different. Heavier buffers help.

Hammers are the same, but I suggest a rounded hammer, NOT a notched one.


Have you considered a 7.62x39 upper? Ammo is MUCH cheaper and it has similar performance.

 

[GunnyHwy]

Have you considered a 7.62x39 upper? Ammo is MUCH cheaper and it has similar performance.

I heard that 7.62x39 has feeding issues in ARs. True?

 

[boricuamaximus]

Dont get another upper. Just stick with 6.8 because it's the best thing since biscuits and spam.

 

[clandestine]

I heard that 7.62x39 has feeding issues in ARs. True?

No it wont have problems if its setup right.

The 7.62x39 setup should have:

M16 Bolt Carrier (Bravo Company)
MGI Enhanced 7.62x39 Bolt Head
Chrome Lined Heavy Barrel
M4 Feed Ramps, Polished
H2 Colt Buffer
Crane or Buffer Tech Extractor Inserts

A 6.5 or 6.8 will have the same issues if not setup right, but the 7.62x39 ammo will be a huge savings.

 

[F-Stop]

Don't want to hijack but, anything else to help with steel case surplus? Or, is that what the Crane inserts are for? Thanks

No it wont have problems if its setup right.

The 7.62x39 setup should have:

M16 Bolt Carrier (Bravo Company)
MGI Enhanced 7.62x39 Bolt Head
Chrome Lined Heavy Barrel
M4 Feed Ramps, Polished
H2 Colt Buffer
Crane or Buffer Tech Extractor Inserts

A 6.5 or 6.8 will have the same issues if not setup right, but the 7.62x39 ammo will be a huge savings.

 

[clandestine]

Don't want to hijack but, anything else to help with steel case surplus? Or, is that what the Crane inserts are for? Thanks

The Chrome Lining and Extractor insert helps with that.