18 replies to this topic

[venom213]

We all love CaptainSlug's Longshot plunger head replacement, so I figured It could be pretty good on other guns. Here is what I did for NFs.

This is the new plunger head, dissassembled. It consists of two 7/8" OD 1/8" ID washers, a 1" OD 3/8" ID rubber washer, a #8-32 washer, and a #4-40 screw (either a 1" or 1 1/4" long)



The #8-32 washer goes inside the rubber washer.



Then just put a 7/8" OD washer on each end of the Rubber washer and insert the screw.



Lastly, screw it onto the NF plunger rod. I used a diskshot plunger rod just as an example.





That's it. Total Cost: about 80 cents to $1.20. I have found that this creates such a good seal that I had to add yet another spring to my NF (which already had a handyman spring) to compensate. I think using smaller washer may fix the too tight seal, but I like having the extra power as is.

UPDATE: 2-22-11

I've tweaked the design a bit out of curiosity. I'll post comparative test results between different plunger head styles when I complete testing.

Here's the assembly spread out. It consists of: 6-32 Screw, 3/4" OD 3/16" ID Fender Washer, 1/2" OD 3/16" ID 1/4" Thick Nylon Spacer, 1" OD 1/2" ID Rubber Grommet, 3/4" OD 3/16" ID Fender Washer, 6-32 Nut, and 1" Piece of CPVC. The nut between the plunger head and plunger rod is a design suggestion that Mr. Badwrench suggested when I did my Overhauled Sharpshooter I.



I drilled down the screw port on the plunger rod with a 7/64" Drill Bit and then tapped it with a 6-32 Tapping Bit. The screw extends into the plunger rod a bit.



Here it is fully assembled. The CPVC may need to be secured in some way in the long term if it has problems with sliding around. The CPVC is on the rod to take stress off of the "neck" of the plunger head. I'm certain this has been done before but I have no idea who did it.





The grommets don't fit well into the plunger tube straight away. It just takes some sanding of the grommet and it will work much better. I rotate the grommet as I slide it down the sandpaper to make it as even as possible. Just a few minutes of sanding usually does the trick. It's nice because it lets you get exactly the amount of friction you need.



PM me if you're interested in purchasing one of these.

Edited by venom213, 22 February 2011 - 06:03 PM.

[Blue]

There was a thread a long while back where a guy replaced the plunger rod, but not the plunger head, this would be perfect for that. You mentioned the seal being too strong... I had a NF that I put an extra O-ring on, and the range went down below stock even with a spring replacement because the friction was so strong. Is this decreasing the ranges it had before?

[Hi Yah]

I too wonder if this will give the gun a too tight of a seal? Also can you over come the friction with lube and a spring replacement?

[venom213]

I too wonder if this will give the gun a too tight of a seal? Also can you over come the friction with lube and a spring replacement?

Yes. There is definatley too much friction for a stock spring. I think there was still too much for just an Ace #49 spring or Handyman spring, so I added a Tek 6 spring in addition to the handyman spring. This is the same deal with the LS plunger head replacement. You pretty much have to add stronger springs with that for it to be effective. I have some ideas on how to reduce the amount of friction though, I'll post my resuts. I think the spring setup that I have now is doing pretty well to overcome the friction. I have 2 NFs that have this mod, they both have industreal springs, but one of them as the Tek6 spring too. The one that has two springs performs much better.

Edited by venom213, 17 May 2009 - 10:47 AM.

[Blue]

I too wonder if this will give the gun a too tight of a seal? Also can you over come the friction with lube and a spring replacement?

Yes. There is definatley too much friction for a stock spring. I think there was still too much for just an Ace #49 spring or Handyman spring, so I added a Tek 6 spring in addition to the handyman spring. This is the same deal with the LS plunger head replacement. You pretty much have to add stronger springs with that for it to be effective. I have some ideas on how to reduce the amount of friction though, I'll post my resuts. I think the spring setup that I have now is doing pretty well to overcome the friction. I have 2 NFs that have this mod, they both have industreal springs, but one of them as the Tek6 spring too. The one that has two springs performs much better.

So does the one with the plunger head replacement and two springs work better than one with the same spring combo and no plunger head replacement?

[Lt Stefan]

I tried this but could not find any fender washers that fit inside the plunger tube. Where did you find them?

[venom213]

Blue: The NFs both have plunger head replacements. The one with two springs (as opposed to one) performs better. Both of them have industrial springs, the one just has a Tek6 spring as well, the other has just the industrial spring.

Lt. Stefan: I got the rubber washer at Ace Hardware.

Edited by venom213, 17 May 2009 - 11:29 AM.

[Hi Yah]

I too wonder if this will give the gun a too tight of a seal? Also can you over come the friction with lube and a spring replacement?

Yes. There is definatley too much friction for a stock spring. I think there was still too much for just an Ace #49 spring or Handyman spring, so I added a Tek 6 spring in addition to the handyman spring. This is the same deal with the LS plunger head replacement. You pretty much have to add stronger springs with that for it to be effective. I have some ideas on how to reduce the amount of friction though, I'll post my resuts. I think the spring setup that I have now is doing pretty well to overcome the friction. I have 2 NFs that have this mod, they both have industreal springs, but one of them as the Tek6 spring too. The one that has two springs performs much better.

Do you think you would get better ranges if you just have two o rings with a little electrical tape underneath them?

[venom213]

Do you think you would get better ranges if you just have two o rings with a little electrical tape underneath them?

If your using just an Ace #49 spring or just a Handyman spring, I reccomend getting two new O-rings and using those. If your using a stronger set-up than either of those springs, do the plunger head replacement.

[Capten Karat]

What kind of ranges is this getting?
I think you should add something behind the plunger head so it doesn't snap off. Like in the LS plunger head replacement. Now all we need is a Plunger tube replacement!

[venom213]

What kind of ranges is this getting?
I think you should add something behind the plunger head so it doesn't snap off. Like in the LS plunger head replacement. Now all we need is a Plunger tube replacement!

The purpose of the longer screw is to prevent plunger head breakage. I have replaced NF plunger tubes before, it's simple. If your using the stock plunger head, use 1" thinwall PETG. If your using the replaced one, 3/4" thinwall PVC should work.

[Hi Yah]

What kind of ranges is this getting?
I think you should add something behind the plunger head so it doesn't snap off. Like in the LS plunger head replacement. Now all we need is a Plunger tube replacement!

The purpose of the longer screw is to prevent plunger head breakage. I have replaced NF plunger tubes before, it's simple. If your using the stock plunger head, use 1" thinwall PETG. If your using the replaced one, 3/4" thinwall PVC should work.

I'm curious where you can get 1" thinwall PETG.

[Lt Stefan]

Lt. Stefan: I got the rubber washer at Ace Hardware.

I have a good rubber washer too, but the metal fender washers are the ones that don't fit.

[venom213]

I got 1" thinwall PETG at Petco. Try one of those or another store that carries aquarium supplies. It is pretty expensive though, I think it cost me about $7 for 3 feet. If you can find 3/4" thinwall PVC, I would recommend that over the PETG.

Edited by venom213, 17 May 2009 - 02:28 PM.

[Lt Stefan]

I got 1" thinwall PETG at Petco. Try one of those or another store that carries aquarium supplies. It is pretty expensive though, I think it cost me about $7 for 3 feet. If you can find 3/4" thinwall PVC, I would recommend that over the PETG.

O so you also replaced the plunger tube.

[Daniel Beaver]

What kind of ranges is this getting?

I test-fired this at the last war, and it got about 70'-75' (about the maximum you can get out of a Nitefinder).

I can see the use of this if you are using a replacement plunger rod, but I generally think that adding an extra o-ring is the best solution if your plunger head is still in good shape.

[venom213]

What kind of ranges is this getting?

I test-fired this at the last war, and it got about 70'-75' (about the maximum you can get out of a Nitefinder).

I can see the use of this if you are using a replacement plunger rod, but I generally think that adding an extra o-ring is the best solution if your plunger head is still in good shape.

Yes. If your plunger head still works, keep it and buy new O-rings. This is only for if you don't have a (working) plunger head, or if your using a stronger spring set-up than an Ace #49 or Handyman spring.

I did not replace the plunger tube on these NFs.

[jason]

i want to buy one

[venom213]

Original post has been updated with my new grommet head version.