Mounting a Harris Bipod On an M1A

Mounting a Harris Bipod On an M1A

I was trying to find out which adapter is required to mount a Harris bipod on a Springfield Armory M1A (woodland camo fiberglass stock)--and I wasn't having much luck. Over at Cabela's, a very nice person helped me pick out the right bipod, the 1A2 L (which is the lightweight version appropriate for prone shooting).

The Harris bipods attach via a quick detachable (QD) stud. The M1A doesn't have a QD stud, so Harris makes QD studs that attach in a variety of ways. Since there is a water drainage hole near the front of the M1A stock somewhat larger in diameter than the QD stud, that's the obvious choice. We picked one that looked the best choice, the No. 2 adapter. When I got home, I discovered that the No. 2 adapter wasn't quite right--and indeed, there isn't a Harris adapter that fits perfectly.

Let me explain. The QD stud itself is a round piece of steel with a hole in one end, and a 10-32 thread on the other. (I could have made this myself, but it wouldn't have been black in finish. For the few dollars it cost, it wasn't worth making it myself.) The No. 2 adapter consists of the QD stud, a washer that goes between the stud and the exterior of the rifle stock, and a rectangular plate that goes inside the stock of the rifle. But that rectangular plate is too large to fit inside the M1A's stock once you put the gun back together again.

There is a small recessed area inside the M1A's stock. It is about .110" deep, and about .875" x .375" width and length. The rectangular plate that comes with the No. 2 adapter was perhaps a little thick, but mostly, it was too long and wide to fit in that recess, so there was no hope of the M1A's barrel and operating rod assembly going back into the stock.

I thought of using a 10-32 nut on the inside, with a washer, but I didn't have a washer that was big enough not to fall through the drainage hole, and yet small enough to fit in the rectangle. And it would have been nice, anyway, to spread the load across as much of the interior of the stock as possible, to avoid damaging it.

Well, that's why everyone needs a vertical mill around the house. I dug through the scrap bin until I found a piece of 1/8" thick aluminum, and then milled it down to .875" x .375". Then I drilled and tapped a 10-32 hole in it. The rectangle fits into the recess inside the stock, and the QD stud goes through the drainage hole, and into the 10-32 hole. Snug as a bug in a rug!

I guess that I am surprised that Harris doesn't make an adapter specific to the M1A stock. There's certainly plenty of them out there.