Is that glass or plastic? (Not the downstem). When you make a bong you need to drill the hole at the angle you ant the downstem to be.
Either try another bottle and go at an angle Or get a downstem that has like an L curve. Hell I have one right here I'd just give away if I could. It's in a bottle bong too, but the bottle is a square. Almost impossible to clear it all in one hit. Wasn't worth the effort.
How do I bend the hole once I heat it? The bottle is glass, the grommet is plastic. I know, I tried to drill at an angle but it ended up flat anyway How would you put the bowl in a downstem with a curve?
If you had a small enough file you could try filing the inside of the hole you drilled to make the proper slant.
You can't bend it because it's glass. If you're careful, you should be able to insert the bit in and slowly grind it upward in order to get the angle you want. Depends on what you're using of course. Might be easier just to get a different bottle, one with a bulb at the bottom so you can drill straight but get the angle.
oh if its glass then you can't do what I said, i thought it was a plastic bottle. find a curved downstem, they make em.
I use a propane torch to heat the downstem and bend it. Then use a rubber gromet in the hole in the bottle. This is my daily driver. I like to pinch the end for a minor defuser, but not enough to cause any real restriction. Here's a picture showing a rubber gromet and a tube bend. I don't use this one much. It's great for leaning back in the recliner.