Plastic/Aluminum hand guard / barrel nut?

[Religious Shooter]

I have a handguard that I had pulled from a Alexander Arms factory upper. It appears to have a plastic hand guard nut. Also rebarrelled a really old upper that has a Clark CF handguard with an aluminum nut.

For a 3 Gun upper, have you guys found any problems (like thermal drift) using non-steel barrel/handguard nuts?

Does the JP handguards use a steel or aluminum nut?

Thanks.

[caspian guy]

I have a clark ar with that carbon tube it is one of the most accurate I own. I also used a number of them in guns back in the day when there wasn't another option for light float tubes. I have never seen a problem with them from a usability standpoint.

[Dan Sierpina]

I too have a Clark carbon fiber tube on one of my AR's. The nut portion is aluminum, with the tube joined with epoxy. The JP has an aluminum part, that is loctited to the upper receiver, with a steel retainer that threads into the aluminum part.

If there is thermal drift with either, you'd probably need a scope with bench rest type magnification (36X+) to see it.

[Religious Shooter]

What I mean by thermal drift is the difference between the POI and spread between a cold barrel and a barrel that's scalding hot. Basically what happens when you shoot a typical stage when you shoot long range targets at the start... run around and engage close range paper... then engage the long range targets again.

In it's current state my 18" JP upper apparently moves 1.5 MOA to the left and .25 MOA up and the group size opens up. This is from a cold clean barrel to a hot barrel.

My other upper with a relatively new Nordic barrel and JP handguard... the POI doesn't shift at all. But the group size increases.

The difference is noticeable.

Just wondering what a plastic nut will do. I guess I can just put it together and see what it does.