A friend of mine has a M1A and wants a bipod. He was going to get the Harris adapter and mount one of those. But then he saw a M2 bipod by Springfield and is thinking about getting that instead. Any opinions? How does the M2 compare to the Harris?

apple to oranges,
the m2 attaches to the gas system, so it most likely will change point of impact when used
the harris mounts to a sling swivel stud on the stock, not the gas system or barrel,
having said that i have a m2, looks great with an E2 stock and sling,

but i don't shoot from it,,

hth

does anyone know with harris adaptor is needed to mount the bipod?  I need a bipod for my m21

Quoted: does anyone know with harris adaptor is needed to mount the bipod?  I need a bipod for my m21

If your going to use the weep hole in the stock, then it's a harris #2a.  

If your going to change out the front sling swivel to a sling/bypod mount, then it's a Type II assembly features a QD stud with removable Mil-Spec Sling Swivel for ease in mounting a Harris Bipod.

www.tanksrifleshop.com/m14_products.htm

If ya want the military look or option you should look to buy the chinese/ norinco M2 bipod. the thing is as every bit as well built and sturdy as a G.I. The G.I. one is parkerized finished while the norinco one is blued. the best thing is they are 1/4 of the price of a G.I. m2 and even cheaper in price than a harris but 10x as sturdy as one. dont get me wrong though, the harris are combat proven and light weight. the mounting option is what will decide a harris or G.I. bipod. You can't really go wrong with either.

The M2 style bipod is heavier and mounted further away from the shooter than the Harris bipod-to-stock arrangement.  For precision, semi-automatic fire, the Harris bipod mounted to the stock is the clear choice.

Quoted: The M2 style bipod is heavier and mounted further away from the shooter than the Harris bipod-to-stock arrangement.  For precision, semi-automatic fire, the Harris bipod mounted to the stock is the clear choice.

The M2 is steel, the Harris is high strength aluminum and is therefore lighter.

Quoted: Quoted: does anyone know with harris adaptor is needed to mount the bipod?  I need a bipod for my m21 If your going to use the weep hole in the stock, then it's a harris #2a.   If your going to change out the front sling swivel to a sling/bypod mount, then it's a Type II assembly features a QD stud with removable Mil-Spec Sling Swivel for ease in mounting a Harris Bipod. www.tanksrifleshop.com/m14_products.htm

How do you install this swivel?  Does someone have a picture of what it looks like installed?

It's really a piece of cake. The #2a is nothing more than a small, curved plate with a threaded sleeve installed in it.  

If you look at the inletting of a wood M14 stock, you'll see a small "well" carved into the area around the weep hole.  All I did was grind away the corners of my #2a mount until the plate fit directly into the well.  Then all you do is mount the Harris bipod from below using the weephole as the entrance for the thumb screw.  It mounts in seconds.  It also dismounts quickly, too.

I tried the M2 version.  I was extremely disappointed with the alteration to the POI on my targets with it.  The rifle shot all over the place.  Maybe it worked fine for full-auto, but for accurate shots, stay away from any bipod that clamps onto the gas system or barrel.  In addition, this is already a heavy rifle.  The aluminum bipods are extremely light.

There is another brand of bipod you can also purchase with is virtually identical to the Harris bipod.  These bipods are made by Shooter's Ridge, distributed by Outers. From what I've read, the patent on the Harris design expired and Shooter's Ridge/Outers copied them virtually verbatim.  They are even sold with the same dimensions.  I mounted the 9"-13" version.  I have one and a Harris and I can not tell the difference, truthfully.  Both the Harris and Shooter's Ridge use the same Harris #2a mounting plate.  

My Polytech shoots sub-moa groups with it on.  I even had a expert marksman soldier try it and he agreed that it was a tack driver and the bipod was identical to what he'd seen.

Rome

The Harris stud just goes threw the weep hole.

On the sling swivel replacement, you drill the heads off the old rivets (inside the stock) and pull them out. The replacement swivel is then attached with either new rivets or the rivets are replaced with two button head allen screws with nuts (you use the old washers in the stock, and this method works better since if the bipod loosen up the swivel plate from tension over time, you can just tighten the screws).

Quoted: It's really a piece of cake. The #2a is nothing more than a small, curved plate with a threaded sleeve installed in it.   If you look at the inletting of a wood M14 stock, you'll see a small "well" carved into the area around the weep hole.  All I did was grind away the corners of my #2a mount until the plate fit directly into the well.  Then all you do is mount the Harris bipod from below using the weephole as the entrance for the thumb screw.  It mounts in seconds.  It also dismounts quickly, too. Rome

Is the #2a then for M1A wood stocks and the #2 for synthetic M1A stocks?

I know for sure the 2A is for wood.  I'm not positive about the #2 for composite.  

Rome

I want to replace my existing sling mount w/a 2a also so I don't have to drill any new holes or use the weep hole - that sounds like bad ju-ju. Could someone post a picture of this set up? I've called a bunch of retailers and there clueless.

Thanks