say a large base ship bumps a b -wing head on the b-wing move is a 2 k turn since a large base ship is the same length as a 2 move does the b wing make it and is just touching or does not make it and bumps if the b-wing makes the move does he get to shoot at the large base ship as no bump

"A ship overlaps another ship when executing a maneuver if its base overlaps the other ship's base. If this happens, move the moving ship backward along the template until it is no longer overlapping another ship." - Rules Reference.

If movement template does not clear the ship, then it counts as an overlap whether you think it should clear or not. That said, if you are touching a large ship head on a 2 straight or 2 K-Turn probably won't clear the ship since the guides on the ship base extended the distance to just slightly over 2.

you cant make a 2K with the B-wing over a large base ship because the Nubs on the ships push the ships far enough that it wont make it.

The large base is NOT the same as a straight-2 template, especially when you take the guides into account. This is a common misconception. Stand a large base on its edge, on the guides, and place a straight-2 template against it. You will find the template will be shorter. The same applies to small bases and the straight-1 template. When you're nose-to-nose with a large ship, it is impossible to make a straight-2 or 2 K-turn and clear the large ship.

When the B-wing attempts to move, it's not going to make it to the other end, so it will move backward along the template until it no longer overlaps the other ship, which will bring it back to it's starting point.

So the end result is:

1. The B-wing has overlapped another ship and is now "touching" and because it is touching that ship, it cannot attack that ship.
2. It attempted a red K-turn but couldn't complete it, so will not turn around (page 6) but will get a stress token.
3. It will skip its "Perform Action" step this round (even if the chosen maneuver wasn't red).

See "Overlapping Ships" on page 15, and "Touching" on page 19.

There is way to be front of each other without having the peg in the way, if you touch a bit to the left or right. Then it could be possible to do a two straight, but you still have to try it.

26 minutes ago, muribundi said:

There is way to be front of each other without having the peg in the way, if you touch a bit to the left or right. Then it could be possible to do a two straight, but you still have to try it.

Nope. Even then, the 2 straight isn't quite the same length as a ship base.

58 minutes ago, muribundi said:

There is way to be front of each other without having the peg in the way, if you touch a bit to the left or right. Then it could be possible to do a two straight, but you still have to try it.

Your own nubs on your ship create enough space that no matter what angle you try it from, a 2 straight or 2k won't clear a large base. You have to take into account that you are putting the template down against your base which is seated back behind the nubs.

34 minutes ago, Jimbawa said:

Your own nubs on your ship create enough space that no matter what angle you try it from, a 2 straight or 2k won't clear a large base. You have to take into account that you are putting the template down against your base which is seated back behind the nubs.

he meant if you are offset.

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U U | |

like that, with the bases in contact. If the 2 were exactly as long as the large ship base, the nubs wouldn't be a factor.

As state above, this still results in a bump though because the large ship base is slightly larger than a 2 move even without the nubs.