Should there be clearance between a freefloating hand guard and the piston/gas block? - Page 1

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[ARCHIVED THREAD] - Should there be clearance between a freefloating hand guard and the piston/gas block?

Posted: 4/21/2015 12:01:01 AM EDT

I have a new freefloat handguard on my Adams Arms piston AR, and it is in contact with the piston block. I am wondering if there should be any clearance between them. Am wondering if things get hot, will there be expansion and then force between them, I have not had time to try it out, was thinking some out will know what is the case.

Posted: 4/21/2015 1:05:02 AM EDT

[#1]

Touching = not free floating

Posted: 4/21/2015 1:23:17 AM EDT

[#2]

Quote History

Quoted:
Touching = not free floating

View Quote

FPNI (yes, there should be a gap/no, they should not touch).

Posted: 4/21/2015 6:22:01 PM EDT

[#3]

Yes, there should be a visible gap. Things vibrate when firing, and things ordinarily in close proximity can make vigorous contact and bend/dent each other.

If it's touching, it's definitely not free-floated.

Posted: 4/22/2015 11:23:01 AM EDT

[#4]

You have to dremel the handguard to have the benefits of free float. You have joined the club of all the people I know with an AA system and a FF handguard that covers the gas block.

What rail is it?

Posted: 4/22/2015 2:46:43 PM EDT

[#5]

I don't remember the brand, the shop installed it and I never had the box, next time I open the safe, will check. This rail does not extend over the piston block, it just touches the rear of the block.

Posted: 4/23/2015 12:42:45 AM EDT

[#6]

Not every tube/rail works correctly with a piston system. The factory AA upper I have is freefloated.

Adams Arms complete 14.5" MidLength Tactical Evo Upper with a free floating Samson Mfg. Evolution Series 9"-EX rail.

Posted: 4/23/2015 8:59:06 AM EDT

[#7]

If you want a specific FFHG you have to get creative. This is the work I did by hand on my Diamondhead HG. It's close but you can get a business card in on all sides. Little filing doesn't hurt anything.

Posted: 4/23/2015 1:29:14 PM EDT

[#8]

No.
Touching = pressure.
Pressure = applied off axis force
Applied off axis force = Decline in inherit precision.

[ARCHIVED THREAD] - Should there be clearance between a freefloating hand guard and the piston/gas block?

AR-15 » AR Piston Systems

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