20 replies to this topic

[SonReeceSonJensen]

Tired of only being able to bitch about reverse plungers and re-shells? You have come to the right place.

This is an idea inspied by the XXL Bazooka. Many have not seen one but if you look at the internals it is entirly powered by a draw spring running the length of the plunger and not a traditional compression spring like in most springers, reverse plunger or otherwise.

First our test subject: the oft mocked but incredibly available, affordable, and commfortable Recon. You can see the draw spring we are going to use there next to the barrel.


Here is the exact sum of what we will be putting into this. And we will be putting it right into the plunger system right about where it is placed here.


Here is a pic of the only annoying part: negotiating the draw spring into place on the bolt. I used a coat hanger with a hooked end.


Here is a shitty pic down the barrel. See all that sweetness in there? Yeeeeaaaaahhhh.


Here is some "hard data" I gathered. I used the same Raider drum filled with the same unmodified streamilines on the same day from the same firing position. The difference is one Recon had basic AR removals done, the other had AR removals and the draw spring addition.


Here is a bit more artistic of a representation. A "big fat pace" is about 3.5 feet. I didn’t care about exacts because I am not looking to measure distance: I am looking to measure percentage increase.


RESULTS: The numbers show an overall increase of minimum, average, and maximum range across the board. Average increased from about 12 paces to about 16, so 33%. Yeah: an average increase of 33% to a normally shitty reverse plunger using about $1 of hardware. On top of that the max range increased 18% and the min range increased about 44%.

Now, I'd like to have run more tests but I'll be straight-up and tell you my clever way of securing the I-bolt was ripped to shreds after 22 shots. Last time I ever not use epoxy for anything.


I would love it if someone beat me to doing this with a powerstock, but that is my next plan. If you like the comfort, look, and ROF of the N-Strike line I cannot recommend this mod more. Also, this is just one spring: I'm sure there are others that could do the job as good or better.

EDIT: Re-mathed

Edited by SonReeceSonJensen, 25 April 2011 - 05:34 PM.

[T dog]

This mod is pretty cool. I really like the internal extension spring idea and am pretty impressed with the increase. A lot of the people I nerf with aren't too serious into modding and use stock darts so this is the perfect mod to use with them. Thanks for the post!

PS. 12 paces to 16 is a 33% increase. Your math teachers weep.

[Blue]

Very cool mod, does the spring ever have issues going into the back of the breach when you use it?

[andtheherois]

It'd be interesting to see what this can do with a power stock, improved seal, and brass breech. You might also want to look into padding the plunger tube somehow since it seems that you're adding a ton of power to that wimpy system.

[SonReeceSonJensen]

Very cool mod, does the spring ever have issues going into the back of the breach when you use it?

Negative. Even in an unprimed state the spring is slightly taut to avoid any wayward movement and the support bolt is well before the stock dart tooth so the whole action is within the basic area of the plunger itself. A longer draw spring might have this issue.

It'd be interesting to see what this can do with a power stock, improved seal, and brass breech. You might also want to look into padding the plunger tube somehow since it seems that you're adding a ton of power to that wimpy system.

Agreed, I have a nice nubile Alpha Trooper that will be getting some less-than-tender-love soon

[SK8R]

Awesome, I'm going to try this on my Longstrike. (If I can fix the bolt sled again )

[ahtanie]

Very interesting!
Good work SonReece!

[Wes7143]

If I'm understanding this correctly, this does the same thing as a power stock, but it's internal? This is really neat if the internal spring you've got in there is powerful enough not to need that pesky outer spring, which makes reassembly of these blasters somewhat tricky.

[SonReeceSonJensen]

Awesome, I'm going to try this on my Longstrike. (If I can fix the bolt sled again )

Yes! Now the most comfortable blasters with decent ROF might become viable arms!

Very interesting!
Good work SonReece!

I appreciate the over-seas love.

If I'm understanding this correctly, this does the same thing as a power stock, but it's internal?

Very good way of putting it: internal inverse power stock. I am, however, seeing the benefit of the screw and support mass that stick out of the back of the plunger tube as a bit of a stabilizer for a power stock if they were the right size and shape.

One other thing: This mod puts pressure on the catch from two different directions as it is using both pulling and pushing force. I’m not sure if this was 100% the reason, but in my mod I used the stock spring on the catch with no issues. If this is a way to distribute pressure on the catch then it might allow for some serious beefy springs.

[Phibonnachee]

So the gun won't actually be primed while pulling back? Since pulling back normally compresses the spring, the pull back in this case would not stretch the spring. Only a forward motion would prime right?

[SonReeceSonJensen]

So the gun won't actually be primed while pulling back?

It will still prime the stock spring, and set the plunger in the catch which is critical.

Since pulling back normally compresses the spring, the pull back in this case would not stretch the spring.

Correct, but only for the added draw spring.

Only a forward motion would prime right?

Also correct, also only for the added draw spring. Since the two do not have any mechanical conflicts when operating I thought it best to use them both. That, and the power.

[Ozymandias]

That, and the power.

There is a Scarface quote in there somewhere...

Have you done this yet to a Raider/AT? I am wondering how the slam fire mech. will respond to this.

Edited by Ozymandias, 13 May 2011 - 01:26 AM.

[Boot]

Have you done this yet to a Raider/AT? I am wondering how the slam fire mech. will respond to this.

I a variation tried this on my AT recently with great results. As mentioned the handle will remain in pulled position by default after the catch has bee set. This is actually useful when using slam fire because the breech will remain open until you are actually ready to fire a shot (although this means no one handed operation.

The only difference in my version was using a U bolt with nuts on the end of the plunger which made everything rock solid.

@SonReeceSonJensen:

Great mod! Mods that are so accessible, simple, cheap and effective are very rare. This is a simple and more reliable method of giving reverse plungers a much needed power boost. Great job!

Edit: Also, genius idea on using the coat hanger. With a custom bent 'tool' it took just a few seconds of coaxing to get everything in place!

Edited by Boot, 14 May 2011 - 08:35 AM.

[WolfHeart]

Hey guys I'm new to Nerf Haven and have only done a couple simple mods so maybe I'm wrong but, wouldn't putting the spring inside the plunger tube decrease the volume of air inside the plunger tube which would lead to lower ranges. Obviously it increased ranges from just the normal AR removal but maybe you could place it somewhere else and that might boost ranges a little bit further. Also, are you using this mod with the stock spring? Thanks.

[taerKitty]

The volume inside a reverse plunger is dead space. Filling dead space is often useful.

[WolfHeart]

The volume inside a reverse plunger is dead space. Filling dead space is often useful.

Okay, thanks.

[SonReeceSonJensen]

Have you done this yet to a Raider/AT?

Negative, but fo SHO I will be amping up my AT soon.

I a variation tried this on my AT recently with great results.

The fact that someone else tried this within days of my posting brings a lot of joy to me. Glad to hear it worked, thanks for the data on slamfire!

The only difference in my version was using a U bolt with nuts on the end of the plunger which made everything rock solid.

I may try this, I was also thinking an epoxy blob on the outside where the screw exits the reverse plunder, and it might also double as a stabilizer for an additional power stock.

genius idea on using the coat hanger. With a custom bent 'tool' it took just a few seconds of coaxing to get everything in place!

: ) I ) There should be no nerfer out there who does not have a mangled, chopped up, and disfigured wire hanger in their toolbox or workspace: I find a new used every other mod I do.

Hey guys I'm new to Nerf Haven and have only done a couple simple mods so maybe I'm wrong but, wouldn't putting the spring inside the plunger tube decrease the volume of air inside the plunger tube which would lead to lower ranges.

No need to apologize, I thought the exact same thing but figured the increased power would outweigh the reduced air volume.

maybe you could place it somewhere else and that might boost ranges a little bit further.

The only other place would be into the tube that runs from the barrel to the o-ring. But my concern would be a blockage of airflow. Likely, however, the increased power will offset that.

The volume inside a reverse plunger is dead space. Filling dead space is often useful.

I’m not 100% sure on this, that would mean that totally filling the reverse plunger would increase range. I believe you are thinking of the straw or pen mod where you decrease the volume of the tube running from the barrel to the o-ring which I seems like it has always had mixed results. I could be wrong, I’m not schooled in these things or every done the math.

[WolfHeart]

Maybe it would work better if you took two smaller springs, equaling about the same strength of the one you used. Then took a bolt and put it through the tube that runs from the o-ring to the barrel like you did, and put another bolt through the plunger tube. That way you could attach them to the outside, and take up less space inside the plunger tube. You would also have to make sure you seal it up so no air is coming through. There may be slight issues with the stock spring but I'm sure with a little tinkering it would work.

[SonReeceSonJensen]

That way you could attach them to the outside.

If you put a bolt all the way through and cut some slots in the shell this would work for sure. However, retaining stock aesthetics was a goal in addition to range for me. But your idea has potential, give it a shot and le us know.

[WolfHeart]

I will.

[WolfHeart]

Well, I tried it and it didn't work as planned. I like your idea with retaining stock aesthetics so instead of putting it on the outside of the shell I kept it inside the shell but outside the plunger. It would have worked except that there wasn't enough room for the springs I had. It may work with different springs or a different shell.