11 replies to this topic

[Buffdaddy]

We've all seen BBB mods - this particular one was the second mod I ever did, way back when I was starting into Nerf. Sadly, I was still using megas at that point, and not sealing things up. But now that I need BBB springs for mods, it's time that I tried again.

The key to it all: #684 838

They come in 4 packs, 2 of this spring (24.8 lb load) and 2 of a much shorter 44.7 lb spring. All for cheap.

Open up your blaster, pop apart the two halves of the back piece, and take out your plunger assembly.

LINK TO INTERNALS DIRECTORY FOR REFERENCE

Pop the rubber plunger head off, long with the plastic disc used as the spring rest.

Take a 1 1/16" piece of 1/2" PVC (yes, that is an exact measurement. Any more, and you can't actually prime the blaster), and file out 4 corners for sliding the plunger rod inside. Take ~1/2 a PVC coupler (without the ridge on the inside), and slide it to be flush with one side of the pvc pipe. Cement in place to make it solid. Slide down the plunger rod, wide end facing the end of the plunger tube. Easy to figure out on assembly; the wide end is supposed to spread the load out on the rest of the tube.



Take that plastic disc and use a 5/16" steel washer to reinforce it. Cut the slice out so you can still slide it back on, of course.


Slide on your spring (should rest against the PVC pipe), slide the disc back in place, and slide back on the rubber plunger head. Replace that by your preferred method; since mine seems to be mostly airtight, I'm skipping that for now.

The front piece with the arrow barrel? Cut that off. I kept mine and placed some CPVC inside it, so I can still fire arrows. Anyhow, the leftover hole fits 1/2" CPVC perfectly. Carve out the inner ridges on the orange piece, epoxy in half of a CPVC coupler, then fill in the dead space with hot glue and 3 layers of craft foam donuts. With holes slightly smaller than your barrel material, of course. Dart stop/plunger cushion combo all the way.



Reassemble everything, and you're set. It's a bitch to prime, relative to some other things, but with a 6" barrel, I hit 90+, and an 8" barrel is passing 100 feet consistently. I got lucky with the stock seal.


And that's that. I need to reinforce the internals a lot more (epoxy putty, anyone?), but for how cheap the materials were, the results are awesome.

[ice]

Stop putting up write ups so fast, you making me feel bad

Excellent job though, I like your work.

[WicketTheModder619]

Dude, when is this role you are on gonna stop? On a lighter note, everything you have been putting has been excellent and this is just icing on the cake. Great job as always.

[utahnerf]

Please don't stop with the mods, this is awesome. No more mod droughts! Great mod by the way.

[popatachi]

Is the catch spring stock? Does it ever "not catch" and slip when priming?

In the couple that I've had with [k26]'s, the catch sometimes slips... I've had to put in a better catch spring and tried to file down the rounded edges of the plunger rod to help it along.

[Buffdaddy]

Is the catch spring stock? Does it ever "not catch" and slip when priming?

In the couple that I've had with [k26]'s, the catch sometimes slips... I've had to put in a better catch spring and tried to file down the rounded edges of the plunger rod to help it along.

Still stock there. As of yet, it hasn't slipped, but I'll be beefing that up when I reinforce everything. It will sooner or later.

[blitz]

Don't paint it PINK!

[Nerfer 91]

This is a nice mod. I have done this before and tried with that spring and the original but found that the original spring had better ranges. I think I had the same amount of material at the back of the plunger tube though so I'm probably wrong.

Also just a suggestion to everyone who doesn't have access to this spring can just use the original bbb spring and about 2 inches of 3/4 in pvc with just a little bit of duck tape wrapped around it and it works almost as good.

Other than that nice mod and Ranges?

Edited by Nerfer 91, 08 February 2011 - 05:11 PM.

[utahnerf]

It's a bitch to prime, relative to some other things, but with a 6" barrel, I hit 90+, and an 8" barrel is passing 100 feet consistently.

[HappyBurnination]

Don't paint it PINK!

PAINT IT PINK.

[jaybo1996]

Just wanted to spread the word before someone hurts themselfs, I tried this with a K-26 and Replaced plunger head. The 8-32 bolt just gave way, and shot into the front of the plungertube. Sounded very dangerous, like, If-it-wasn't-screwed-together-it-would-have-broken-the-light-bulb-above-me dangerous. In future projects, I'm only doing this mod with stock plunger heads.

[BrokenSVT]

I did a [k26] + replaced PH and it has been fantastic through hundreds of shots. The trick is to over-build the assembly by using a nut + bolt.

Sweet setup using the stock PH though Buff.