Hi everyone.
I'm a new member with my 1st AR. It is an Eagle Arms preban that I bought at a gun show and immediately brought home to analyze parts and serial # to verify it was a legal preban.  Everything seemed fine but it had an M16 trigger. I took it out and replaced with Bushmaster AR trigger but now my hammer sits  high.  Do I need to replace all the lower parts? Any ideas would be great. Thanks

[url]http://www.biggerhammer.net/ar15/hammers/[/url]

If you have a modified M-16 hammer (auto sear tab ground off), You will need to roll file the top edge off to match the profile to the L cut hammer.  You don't have to make the L-cut, just remove the tip metal down to match the L-cut radius profile.

Note: Look at the top two-right hammers.

Thanks Dano523
I checked the hammer and it is the hammer with the L cut (typical AR hammer).  I again put in the new trigger and the bolt carrier drags.  Putting in the M16 trigger it works fine. I did not file anything yet because it doesn't appear to be altered.

The difference between the your two triggers is that the M-16 trigger has a longer front section to sear area, which is holding the hammer a bit lower.  

The two options are to lower the bottom of the L-cut where the firing pin is dragging to use the 15 trigger, Or If the 16 trigger is the only item in the FCG that is a 16 part, then just put it back in.

The law reads that "intent to produce" means that the rifle has to operate as a MG.  Since the only differences between the two triggers are that the 16 (A1 single slot) has an open back, and the 15 a closed back, there is no intent with the single part in the rifle. If you feel compelled, just use a welder and close the back slot of the 16 trigger and it's a 15 part.

Thanks again Dano
As long as I'm legal thats all that matters because it sure shoots great.