Why would a power tube tip severe ???

[chafnerjr]

Weird question... I was working on my first mag. All of the fun tuning and swapping crap around with a buddy of mine who is familiar (not great, but familiar) with tuning mags. And we were having trouble cycling the gun. You'd get a few good cycles and then it would stick and you could either re-gas the gun or press on the end of the bolt to reset it. We had to adjust the sear length all the way out to get good contact on the on/off and even then it would only cycle semi-regularly with the pressure on the valve almost all the way up. Seeing as I knew there would be more mag folks at the field I figured that I'd tune it the rest of the way when I got there...

So I get to the filed. Fire the gun and instantly I'm chopping paint. At first I thought it was the halo and bad paint but it was def. breaking on the bolt. Seems that the soft tip disappeared. No biggie... so I swapped it out with another lvl10 (un-tuned obviously) and I started to have cycling issues again. So I pull out the valve and had some trouble doing so. To make a point I didn't yank it out! I actually did the right thing and one the the local mag guys (he was rockin' his new X that day!) and he told me to puch the valve back in all the way, pull the trigger and then pull the valve out. This worked great.

Here's this kicker. Most of my power tube tip was still in the lvl10. It was not stuck there as it just came out when I turned it over in my hand and the rest of it was still in the power tube... Does anyone know what the heck is going on?

P.S. I think I am having issues with the frame being run mechanically as well. I should have it penu'ed shortly but here's the list of the parts that seem to relate to the issue.

RPG Priah body
Pewter X Valve with lvl10 and ULT (essentially un-tuned)
Cyberave rail which was milled from a stock MM rail
Brand new sear assembly and screws (field strip and such)
Ceberus AirWalk v2 frame with VBP

Anyone have any ideas?

[Spider-TW]

It is most likely from over tightening the tip with a wrench. Brass is much softer than stainless and it is easy to forget to be gentle with it. I tighten mine until the shoulder touches and leave it at that.

1) The original power tube tips had "coin slots" and that was all you needed to work with, no wrenches.

2) My tip came unscrewed ONCE and my mag would not fire. I screwed it back in with my fingers at the chrony table and then shot about 1500 rounds with it. The oring was very old, and I didn't tighten it enough for all the oil on it. A little beyond finger tight is all it needs, you just need to check it when you clean it.

[chafnerjr]

I can accept that. Thankfully I can't take the blame on that one as I just bought the valve used. Luckily it's only a $10 part!

[Spider-TW]

Yeah, there's no telling with used markers. The discovery goes on long after you open the package on those. Some of us had never heard of broken power tube tips until they started making them with wrench flats.

[chafnerjr]

At the very least it's only a $10 part... I am wondering though if the missing bumper had anything to do with it... when I got it there was no bumper for the bolt... who knows. The new tips get's here tomorrow. :D

[questionful]

Were you shooting it without a bumper?

I just tighten the powertube tip with my fingers. Doesn't seem like it'll ever come loose.