Siezing up....

[1996XJ]

Anyone ever had the powertube catch on the end of the TPC while shooting?

I just got in parts for a microphantom and testfired it today.  After maybe 25 shots i decided to use the AT and the bolt ended up getting locked in the closed position.  I stick in another 12g and it goes straight put the barrel so i know the powertube is stuck open.  I assume the power tube somehow came out of the TPC tube while shooting.

Could it be caused by low airpressure behind the valve or possibly a powertube milled to short?

Any suggestions?

[Puck]

Is this a new Phantom or one you just modified to be a Micro Phantom?

[1996XJ]

The internals and grip frame are from my GF Phantom, the rest is new.


I think the power tube may be slightly crooked.  When i assemble it the powertube tries to catch on the outside ot the TPC tube.

[splattttttt]

http://idriders.com/ThePhog/index.php?topic=833.0

[1996XJ]

That doesnt seem to have anything to due with my issue.

[Fireball]

Check that you have not overtightened the rear thumbscrew - I have never heard of a bent powertube.

[1996XJ]

Check that you have not overtightened the rear thumbscrew - I have never heard of a bent powertube.

When i first put it together the powertube kept catching on th TPC and would compress the valve.  I figured once i put it together the powertube would be to long to slide out of the TPC, but apparently i was wrong.

[thkyle]

Once it's together it won't come out, but the walls of the TPC are thin, and you can damage it if you force the valve and tube to go up into place before it's centered up.

Same with the anti-kink sleeve on the front of the hammer. If you drop the bolt on a hard surface, you could have peened over the edge so that the spring doesn't fit in it like it should. It also won't fit into the back of the bolt now because it's egg shaped and snagging on the spring. Both the anti-kink sleeve and the back of the bolt are slightly beveled to guide the two parts together when you pump the gun.

On all of my Phantoms the power tube is inside of of the TPC anywhere from about 3/16th to 3/8 of an inch depending on where the TPC is set. There is no way the power tube could come out of the TPC when the valve is up tight to the body of the receiver.

Maybe......maybe if the valve spring was broken and the TPC was set to the lightest position (all the way to the front of the bolt) it could clear the TPC, but I doubt it.

[1996XJ]

I inspected all the parts and put it back together, once the 12g was almost empty it siezed up again.  The power tube is getting stuck open.

I swapped the dropout changer into my backbottle Phantom and the same thing happened, so im almost positive that its the dropout changer.

Here is a pic

[thkyle]

So, did you take the retainer off and inspect the parts in the valve on the drop out changer?

[6speedblazer]

Once it's together it won't come out, but the walls of the TPC are thin, and you can damage it if you force the valve and tube to go up into place before it's centered up.

Same with the anti-kink sleeve on the front of the hammer. If you drop the bolt on a hard surface, you could have peened over the edge so that the spring doesn't fit in it like it should. It also won't fit into the back of the bolt now because it's egg shaped and snagging on the spring. Both the anti-kink sleeve and the back of the bolt are slightly beveled to guide the two parts together when you pump the gun.

On all of my Phantoms the power tube is inside of of the TPC anywhere from about 3/16th to 3/8 of an inch depending on where the TPC is set. There is no way the power tube could come out of the TPC when the valve is up tight to the body of the receiver.

Maybe......maybe if the valve spring was broken and the TPC was set to the lightest position (all the way to the front of the bolt) it could clear the TPC, but I doubt it.

this is EXACTLY what happened to my phantom and was causing it to jam.

the power tube was comming out of the TPC and making the internals either kink or jam

[1996XJ]

Well i got in the new triggerframe/.45 and internals for it.  The powertube appears to match the new TPC alot better than before, and the siezing problem seems to be solved.

Now i just have to get the velocity up.  I have the TPC screwed in almost all the way with the silver spring and couldnt get it above 238FPS, hopefully the red spring will solve this.

[Unimoose]

Well i got in the new triggerframe/.45 and internals for it.  The powertube appears to match the new TPC alot better than before, and the siezing problem seems to be solved.

Now i just have to get the velocity up.  I have the TPC screwed in almost all the way with the silver spring and couldnt get it above 238FPS, hopefully the red spring will solve this.

check your paint to barrel match, if your losing air around the ball or having it roll forward before firing your velocity will never be good.

[1996XJ]

Well its a micro so i figure im limited to CCI unless i want to chop a barrel, i dont really care for inserts.

Im using detents.

The odd part is that im forced to run the blue spring on my regular phantom just to get the velocity below 300 which is with a 14in CCI barrel.  This is with the same field paint.

Is a large velocity drop normal with the 6in barrel.

[splattttttt]

You're using 12g, so all I can think of is that in hot weather the co2 is expanding too fast. Try a harder valve spring.