I recently traded for one of these and I don't really know much about them. I took it to the range and fired it and sometimes the hammer would follow the bolt forward as it cycled. I got it back home and dry fired it some and the hammer will follow the bolt forward if you hold the trigger back as the action cycles, like the disconnector isn't catching the hammer.

I pulled out the trigger group and compared it to the one in an M1 and they look basically the same. Nothing looks off about the M14's hammer or disconnector. What could be the issue here?

The hammer or trigger is worn...They interchange with the m1. Swap one at a time until it works correctly.

Polytechs are good guns, with a couple of minor problem areas. Those problem areas are easily correctable.
#1.  Hammers and triggers can be soft.  As was stated, replace with USGI Garand or M14 parts.  Essentially the same thing.  Not hard to do, though a bit of a PITA sometimes getting the trigger pin back in place.  I recommend replacing the trigger pin at the same time.
#2.  Issues with the sight knob.  Usually it is the spring in the elevation knob that is soft and won't hold tension, so the knob won't hold zero.  Replace with USGI Garand(marked up to 1200 yds) or M14(marked up to 1000 meters).  Do NOT use a WCE marked M14 knob if you can avoid it.  
#3.  Op rod spring is often a bit undersized and soft.  Replace with USGI.  Might as well replace the hammer spring while you are replacing the hammer and trigger.
#4.  Stock is ugly and soft Chinese Chu wood(later ones have walnut).  USGI stock is a drop in, though a small spacer may need to be added next to the disconnector pin.
The biggest issue Polys have are their bolts.  Which are not made properly, however, they are not unsafe.  Head space runs a bit long, to military standards, not commercial.  Which shortens already short brass life if one is a handloader.  The fix is to replace the bolt, which can be simple, or not.  But, most people don't and don't have any problems.
Other than that, Polys have good forged receivers, good chrome lined barrels, good trigger guards.  I have 3, and I have fixed all these issues, whether they needed it or not.

Thank you very much for that information. #2 is actually something else I had a problem with. I could get the windage right but never the elevation when I went to function test and zero.

Where would I get the parts to replace mine with?

Poly / Norinco trigger groups are usually pretty decent.

Havn't had one for awhile but if the sear has the M14 type extension make sure it isn't catching or dragging on inside of stock.

My brother has a polytech and it's a good gun.  It does have a USGI trigger group in it thought.  The original one didn't work well either.   His also has USGI rear sight and USGI FH with front sight.  It does have the chinese bolt with no problems thus far.  He doesn't shoot it barely ever.  But I've shot it before.  In fact I owned it for a little bit.  We traded for something.

I think this may actually be my problem. I took it out of the stock, put the trigger group in it, dry fired it and I can't replicate the hammer follow. It does it every time when it's in the stock and I dry fire it.

This doesn't make sense. I put the trigger group in the stock to test the fit and nothing even comes close to rubbing the stock. I don't know why the trigger group works without the stock, in the stock alone, but not together with the rest of the rifle, complete.

We had this issue with the M14S I bought my youngest son.

The way we fixed it was to remove a little bit of material from the top of the stock (you could take it off the bottom, I've been told, but that looked to be more work).

The distance from the receiver to the area of the trigger housing where it meets the stock is a bit too far.  The bolt is pushing the hammer back but the sear can't quite catch the hammer hooks.  I just used some rough sandpaper to remove a little bit of material, then put it together and tested it, took it apart and removed a little more material, repeated till we got consistent proper functioning.  Be sure to take material off evenly where the receiver contacts the stock.  Oh, we had put it in a GI synthetic stock.  The wood stock was butt ugly.

It's worked fine for about 5 years now.  He killed his first deer with it not long after we fixed it.

May not be what's wrong with yours but that's what ours was doing and that's what we did to fix it.

I have no idea if ours has the original trigger housing/assembly in it or if it was replaced.

The M1A and the M14s can use the same front and rear sight parts as the M1 Garand.  They also use the same hammer, trigger, hammer spring/guide, safety, lower handguard snap/clip, and extractor/extractor spring.

Good luck with yours.

The fix described by M1A4ME is somewhat common.  It doesn't take a lot of wood removal to do the fix.  Taking too much wood out will make the trigger guard loose.

As for where one can find parts.  Amherst Depot, Sarco Inc, Numrich Gun Parts, EBay, Gunbroker, Fulton Armory.  To name a few. If your gun still has the fake Chinese flash suppressor, it's easy to replace.  However, for best results one needs Castle nut pliers, which is another tool to buy.  I think the functioning FS is better looking than the fake one.  But, since I live in sunny Kommifornia, I can't install one on my guns.

That has to be the problem then. The stock it's in doesn't seem like soft wood. I think it's been replaced with a walnut stock at some point, but I could be wrong I don't know much about wood.

I will take some material off the top of the stock where the receiver sits and see if that works. The trigger group is a bit difficult to close so maybe that will alleviate that too.

I think the flash hider has been replaced at some point as well since it's actually functional. It's not the one that has the metal between the prongs to fill the gaps. I think that I would like to use a suppressor on it but I guess that I can't just take off the flash hider and thread it on since the front sight has to go somewhere.

Can we get some pics?  Of the whole gun?  

Don't take any off the top, under the receiver.  Take a little, and I mean a "little", off the small area under the pad at the rear of the trigger.  Trigger guard lock up is supposed to be tight.  Often, with new guns/stocks, it is not unusual to see the trigger guards hammered closed with a rubber mallet. It does help a little to put some grease on the locking tabs inside the trigger guard.
Does the stock have a cut out at the rear of the receiver corner?  Does the wood seem fairly uniform in color with visable grains stripes?  If so, then more than likely the stock has been replaced with a military stock.  If it lacks the cut out for the selector switch, then it is probably a commercially made replacement.  Those are often a bit thick under the trigger housing pad.

This fixed the hammer follow. Thank you.

The stock doesn't have the cut out. It did come with a synthetic stock that had a cut out but someone epoxied in a filler and painted over it. I only discovered that when I went to strip the nasty black paint off the stock that they used to cover the selector cut fill. Yes the wood seems uniform, it looks like the same type of wood that I have on my Garand that came from the CMP, which I presume is walnut.

I'll see if I can take some pics tomorrow and post them.

I had the same problem with my Polly when I switched to a used USGI stock. Check the lock up. Mine was a little loose, so I added a little wood under the trigger guard.I have not had any issues since.

When I tried to put my Brother's poly into a different stock, it wouldn't fit.  It seemed like I would've had to take some off of the stock where it contacts the front receiver lugs.  I didn't want to do it because I wasn't sure I wanted to have that stock dedicated for it.  The upside to the chu wood stock was it was light.  Seemed lighter than USGI synth.

I've seen this problem with M1 rifles when the stock isn't fit correctly.