Inner Tubes blow in same place

As above I've bought a silly deep wheel and I've tried three different type of tubes and they keep blowing in the same way and the same place near the valve.

It didn't come with velow but I used a shit ton of electrical tape, like I have done in the past but decided after the second one to buy velox. It is occuring directly above one of the spoke holes but there is no sharp edges or anything?

What else can I check before I cut my losses? You can see an indentation on the opposite side that wasn't there before

https://i.imgur.com/IPbWZEh.jpg

What pressure are you pumping them up to and is the rim tape wide enough? The only thing I can think of, is that the tube is "ballooning" into the spoke hole and bursting.

That doesn't look like a penetration of the tube (by something sharp) and the dimple on the other side suggests the same thing is happening there too.

10mm velox and two wraps of tape 100psi it popped almost immediately.

Two wraps of tape then the velox

.

Oh yeah not using the nut on the valve either

I've put another tube on, inflated to 80psi and gone around the block

Let's see how it fairs

Move the tyre 90degrees and mark it? Could be the bead

Not a bad idea. I always put tyre in same place. It got me home (12miles) but I feel it should have more pressure

Vittoria tube per chance?

Looked again and saw that you said you'd tried 3 different types of tube.

We got Vittoria tubes last time at work n they were shit, pretty much all blown in that spot.

Velox has the holes for the valve so you overlap the ends yeah?

Yea overlapped.

One was the slime one from my other wheel. Then an old conti (unused) one and I bought some vaaerts or something. Some Planet X cheapos. The second of which is on now

How close to the valve stem does it keep blowing?

Is the lack of retaining nut ( the one that scares onto the valve stem that stops the valve moving up and down ever so slightly in the rim) making it rub on a burr inside the hole?

No burrs, ran an ear bud after I didn't cut my finger on it.

The photo shows where