Carb too high

[Coadinghaylor Creations]

Brewers! OK...I am not a newby...I have brewed well over 100 batches...but something new has crept up...My bottles are over carbing? Even with NO priming sugar and 6 weeks in the 2ndary...this is NOT an infection...beer tastes fine...just have to dump a bottle into a 3L pitchaer and wait 10 min...tastes fine...spot on...nothing off...beer judge friend agrees...?

16oz pint DAB bottles...sanitized as always 2X...gravity fill...oxygen caps...no foaming during filling...2 weeks @ 64f and then into cooler @ 38F...after only 6 weeks...the 8.8 DIPA is saturated...totally!

Yeast is a triple built up starter of W1272...about 1/2 gallon of slurry for 15 gal batch...bottled at 1.004...beer still at 1.004 if I degass?

Ideas? Temps? Yeast? I have the same thing happening with a 1056 as well in a choc stout? Nothing in my process has changed, and I have 2 year old ales (6%) that are fine...I have NEVER had a bottle bomb...ever?

 

[sbaclimber]

...bottled at 1.004...beer still at 1.004 if I degass?
...
Ideas

Seeing as the gas has to come from somewhere, and the most obvious place would be fermentation...I can only think that your device for measuring the specific gravity is no longer working correctly.
I went through a phase of too highly carbonated bottles and was measuring a ~0.004 drop in gravity during bottle conditioning (which in addition to the priming sugar produced too much CO2).

 

[Nosybear]

Are the bottles overcarbed or are they gushing? I have some "gushers" in my basement, not at all overcarbed but I made an error by adding chalk to the mash. Further reading in some of my chemistry references, you develop little apatite crystals under those conditions, leading to about the same effect as dropping a Mentos into a 2-liter soda bottle: It gushes. From what you say, about ten minutes in a pitcher and the foaming subsides? That sounds like there's not too much gas in the bottles, it's just being released too quickly.

How'd you get the beer down to 1.004 and where did it start?