When my BCG is not in battery (say an inch away or so) and I rock my
thumb on the forward assist plunger (toward the receiver, not away from
it) the forward assist will move so the inside nubby thingy will not
contact the ridges on the side of my bolt carrier. It will miss it
entirely and the forward assist plunger will go completely in but not
move the carrier. If I rock the forward assist plunger the other way
(away from the receiver) it engages the carrier and works as intended.
Has anyone else experienced this and/or is this normal?
My BCG is a Young Manufacturing.






 

what do you mean by rock away from the receiver?

It slightly moves side to side inside it's little hole. Wiggles?

If what's happening that I think you mean, the Young carrier does not have the FA(Forward Assist) notches milled as far forward on the carrier as other carriers.  So if the bolt is far enough out of battery pushing on the FA may or may not be able to engage the notches on the side of the carrier and thus assisting the carrier forward.  But this is just a guess.

Notice the picture of the two BCGs.  The top one is a Young carrier and the lower one is from a Bushmaster.  Notice how the Bushy carrier has the notches milled further towards the front end(toward the bolt locking lugs) of the carrier.

No, this is not the issue. For instance if I put the bolt into battery and push on the forward assist plunger, it contacts the bolt carrier notches correctly, but if I rock my thumb to the left it causes the forward assist plunger to move left slightly and the plunger point to move right I guess and then the plunger goes further forward than I believe it should and never contacts the carrier.





Nice photo comparison by the way.
 

Its not the BCG its the FA or the hole for the FA is a little to large.  Try a new FA button and it might work better.

Sounds like the FA is not assembled correctly.

The notches on the front of the carrier are not used anyway when the bolt is nearly closed and they are not at all part of this problem.

Also, If you are 'needing' to use the forward assist at all, You likely have other issues that need resolved. A properly functioning gun does not really 'need' the forward assist.

I can understand why you want it to work,  But I would suggest trying to find out what is causing the hangup in the first place. The carrier 'should' be sliding home without a problem.

it sounds like you're worried about a tiny amount of movement on your forward assist when you have it pushed all the way in.  Is that what's going on?  You push the forward assist all the way in and it wiggles a little when its pushed all the way down?