PDI hop up help!

I had sort of the same issue, and then I realized the adjustment screws were blocking the cylinder head from entering the chamber. One fubar'd screw and a grooved cylinder head later, I have a working gun. And try adjusting the little plastic ring INSIDE the receiver, make sure the more rounded side is facing out, and the totally flat side is facing inside. I had the same issue with the barrel, just took some patience, fidgeting, and a lot of silicone spray to finally work.

acer34p3r said:

I had sort of the same issue, and then I realized the adjustment screws were blocking the cylinder head from entering the chamber. One fubar'd screw and a grooved cylinder head later, I have a working gun. And try adjusting the little plastic ring INSIDE the receiver, make sure the more rounded side is facing out, and the totally flat side is facing inside. I had the same issue with the barrel, just took some patience, fidgeting, and a lot of silicone spray to finally work.

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Yeah I did that with the screw as well :lmao:

The nub they give you is crap. Use a metal bar, a thick wire works pretty well too.

Cheese Man said:

The nub they give you is crap. Use a metal bar, a thick wire works pretty well too.

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Going to change my nub as well then. Do you know what size bar it needs?

For a nub in the PDI chamber, people have reported success by using a pen ink tube. Like, the plastic tube inside of pens (any old pen like a bic pen will do) that holds the ink. Some complain that the ink tube is too hard, but I think that stiffness means consistency, while flexibility is opposite. I even managed to use an old Lego flagpole piece and cut it to fit.

What you could also do is use an SCS or PCS or H nub (which would be pointless if your bucking has a concave nub or anything like that inside like a PDI W-nub bucking, but useful if you have a flat nub or no nub). Simply use some non-drying modeling clay to "stick" the nub to the hop up arms. You can easily find some of the clay at a Walmart or Target in the arts & crafts section. When you stick the nub on though, you'll have try and make it as centered on the arms as much as possible.

Like I mentioned in another post, I found a nail that was roughly the same diameter of the nub/space needed. Cut it, sanded it, and I have not had any problems since. Like what lulukchoo was saying, from my experiences stiffness means consistency.. but I'm no expert.

I have a PDI vsr-10 hop up chamber in my TM- vsr-10. I have an SCS nub installed in it as well with a ground-smooth bucking. I used thick 3M stick foam, did some very small measurments, and cut out tiny perfect size pieces (exacto kinfe) to secure my SCS nub in the middle (over the barrel window). Took some time, but Im satisfied with the results.