SOLUTION!!! Swivel studs for AR free float handguard?

[bigbob76]

I have 2 threaded holes at the front that I was assuming were for a bipod. They are different sizes. I bought a YHM swivel stud and it's too big. I have a Harris bipod that will mount on a swivel stud, any ideas?

I bought and installed this from Midway. Their product # is 411179. JP Enterprise Inc. JP hand guard floating stud adapter JPHGS. I removed the gas block and slid the threaded plate inside the tubular hand guard. It comes with a rubber O ring on the threaded stud but being an aircraft mechanic I couldn't bring myself to use that. I experimented with little stainless washers until I got the thickness that would give me the correct orientation of the swivel stud when tightened. I used thread sealant and while I had the gas block off I used the Dremel to make some dips in the bull barrel for the set screws on the gas block. I put the Harris bipod on and it worked out great.

[aplinker]

Whose handguard and what do the holes look like? Could be they were drilled for mounting a rail

[bigbob76]

I don't see any brand names on it. It's a varmint upper and I think it was J&T or J&A that I ordered it from. Do you know how to take it off? I wonder if it unscrews?

[aplinker]

Post a pic... there are a few different versions.

[mltrading]

I have 2 threaded holes at the front that I was assuming were for a bipod. They are different sizes. I bought a YHM swivel stud and it's too big. I have a Harris bipod that will mount on a swivel stud, any ideas?

If your YHM swivel stud is larger than the existing holes, you may enlarge the hole and thread it. However you need to know the thread size of the swivel stud first.

[bigbob76]

The best info so far is once again from somebody that had the same experience. They tried the most obvious solution of drilling and tapping to the same size as the threads on an available swivel stud and it ripped loose during the first use of the bipod. After that they used a stud with a long threaded section intended for a wooden stock, cut it to length and put a nut and washer on it. That's what I'll do.

[ar15barrels]

YHM handguards have the larger threads for their screw-in studs.
These are around 5/16" or so.
The small screws on a YHM handguard are 6/32 or 8/32 and are used for rail sections.
Most swivel studs with machine screw threads will be 10/32.

Drilling and tapping an aluminum handguard for 10/32 rarely lasts a long time.
I have steel thread inserts that I install from inside the handguard and get pressed into place.
I have never had one of these strip out.
They are much easier to use than installing a steel nut inside the handguard, though that does work good too.

[bigbob76]

Solution!!!

I bought and installed this from Midway. Their product # is 411179. JP Enterprise Inc. JP hand guard floating stud adapter JPHGS. I removed the gas block and slid the threaded plate inside the tubular hand guard. It comes with a rubber O ring on the threaded stud but being an aircraft mechanic I couldn't bring myself to use that. I experimented with little stainless washers until I got the thickness that would give me the correct orientation of the swivel stud when tightened. I used thread sealant and while I had the gas block off I used the Dremel to make some dips in the bull barrel for the set screws on the gas block. I put the Harris bipod on and it worked out great.