This mod is also applicable to other Nerf N-Strike blasters with reverse plunger setups (ie. Raider, Deploy, Longstrike, Alpha Trooper etc).
Background:
For a background of what a Brass Breech is and what it does, please refer to the Longshot "Brass Breech" Mod Guide.
Introduction:
This mod guide will look very similar to the Longshot "Brass Breech" Mod Guide as they follow a similar modding process, but there are some specific differences in parts measurements, positioning and fit that modders will have to take note of.
To establish expectations, due to the smaller reverse plunger setup in Recons (or any of the other reverse plunger blasters), the potential performance gains will naturally be much less significant than in a Longshot.
Important Note:
The "Brass Breech" mod is a more advanced mod project that should only be performed by those who are already familiar with modding the Recon.
For new modders, refer to the Nerf Recon Mod Guide to get familiar with the modding basics first.
Disclaimer: Modify at your own risk. Modifications may wear out or damage your blaster. Please be careful when using hobby tools!
Lets begin...
Step 1:
You will need to obtain 4 different sizes of brass tubes (Brand: K&S Engineering).
The brass tube sizes are: 1/2", 17/32", 9/16" and 19/32". All of them are 0.014" wall thickness. They are usually supplied at hobby shops in either 1 ft or 3 ft length tubes.
Oxidization tends to occur in store bought supplies, so give the brass tubes a good polish with some Brasso Metal Polish, polish both externally and inside the tubes, this helps smoothen out the surfaces for lower friction.
Step 2:
We will work on the barrel and bolt receiver first.
In this example, i'm using 6" of 9/16" brass tube for the barrel.
Take a Rotary Tool with a cutting wheel, and cut a 7.5 cm length bolt receiver half-pipe in the 9/16" brass tube.
Use a sanding bit to round out the edges and corners.
Please be careful when handling such hobby tools, wear protective eyewear, dust masks and gloves.
Step 3:
To help the chambered darts achieve an even tighter air seal, make tightening rings in the barrel.
Use a Rotary Pipe Cutter and create the tightening rings. Just tighten the pipe cutter slightly around the brass tube, then rotate. Do it a few times to create the tightening rings.
Okay, that's all for the brass barrel and bolt receiver, you can put it aside for now.
Step 4:
We will now go on to the bolt section of the breech.
Separately cut out a set of brass tube sections in the following lengths:
1/2" brass tube: 10.5 cm
17/32" brass tube: 3 cm
9/16" brass tube : 2 cm
19/32" brass tube : 14 cm (4 cm for bolt half-pipe)
These are my custom tube measurements for a breech system for the Nerf Recon that can chamber standard-sized darts. In addition, it also features a more secure "half-pipe" bolt attachment point design.
The measurements need to be as accurate as possible. Any variations may affect the overall structure and air seal of the breech system.
Step 5:
Cut the original stock plastic bolt at the section shown below.
Nest all the 4 brass sections for the bolt completely into the plastic bolt end-piece.
Here is my Nested Brass Tubes Cut-Away Diagram for the Nerf Recon:
Use the strongest glue you can get to glue everything together. I use slow-curing 2-part strong epoxy glue. Make sure the glue cures completely for maximum bond strength.
Completed nested brass bolt assembly.
Nested brass bolt internal assembly.
Step 6:
We will now need to do a test alignment of the various components.
Secure the brass barrel inside the original orange plastic barrel by wrapping it with electrical or duct tape to temporarily widen it's outer diameter, so that the brass barrel can be wedged tightly inside the plastic barrel, yet still movable to allow adjustments for test fittings.
Check all the part positions and make sure that a clip with a standard-sized dart can fit nicely into the breech opening.
Note that the 19/32" brass bolt half-pipe will slide over the 9/16" brass barrel half-pipe, which in turn slides into the brass bolt assembly.
Step 7:
To attach the brass bolt to the bolt sled, we will need to cut out the attachment piece from the original plastic bolt.
Position the brass bolt, attachment piece and bolt sled in the casing and note the maximum forward and backward movement of the bolt to find the correct point to attach the plastic attachment tip to the brass bolt.
Note that a segment of plastic behind the attachment point has to be trimmed thinner so that it can slide into the plunger casing properly. Just whittle it down until it fits.
Use some sandpaper to roughen the surfaces on the plastic attachment tip and brass bolt, then use the strongest glue you can get to glue the 2 parts together. Again, i use slow-curing 2-part strong epoxy glue here too. As always, make sure the glue cures completely for maximum bond strength.
This is the section that has to take the most load, especially when stronger springs are used.
Step 8:
Assemble everything together into the casing, note that the pop-up blocker plate mechanisms are all removed, we don't need those anymore.
Step 9:
Test your "Brass Breech" Recon!
Breech open.
Breech closed.
Once you are confident that everything works properly, you can then proceed to permanently glue the brass barrel inside the orange plastic barrel. DIY some plastic spacer rings along the brass barrel to keep it centered within.
Its complete!
Sample Test Fire Results:
PTG: Parallel-To-Ground (Shoulder height, no elevation)
ATG: Angled-To-Ground (Aimed higher, 30 degrees elevation)
Distance is measured at where the dart lands (Average of 5 darts). Brass Barrel Length is 6".
Brass Breech Recon (AR Removal & 11kg Load Aftermarket Spring)
PTG = 60 ft
ATG = 70 ft
Note that the test was done indoors and the results are sample estimates for reference (your results may differ depending on materials and mod techniques used).
Important Usage Tips:
- Clips must be loaded only when the breech closed. This is so that the clip feed-lips can "catch" around the brass bolt for a proper fit.
- For smooth dart chambering process, make sure that foam darts used are no more than 7 cm in length.
- The better the foam dart fit in the brass barrel, the better the range results.
- Due to the smaller air volume of the Recon reverse plunger, using longer barrels may cause the foam darts to get stuck as it doesn't have enough power to propel them out. If that occurs, reduce the barrel length and test again.
Hey SG- Can I assume correctly that the reciever and bolt can be cut down so a clip can be loaded when it's open, just as you did with the longshot breech?
ReplyDeleteMatt,
ReplyDeleteIf you are referring to the alternative "quarter-pipe" method of cutting the barrel and bolt sections, like this:
http://modworks.blogspot.com/2010/07/nerf-longshot-brass-breech-mod-update.html
Yes, that can be done for the Recon too.
The brass breech mod for the Recon is basically the same as for the Longshot, just with shorter dimensions. :)
Cool, thanks. I was going to do this to my alpha-trooper, i'll let you know how it goes and if measurements need to be different. The recon plunger tube and the AT's plunger tube are about the same size though, i'm expecting to only have to mess with the barrel length of brass. we'll see...
ReplyDeleteAlso, I'm about to make your version of the angel breech with the quarter pipe design. I wanted to leave the bolt section as a half-pipe instead of a quarter pipe since i'll be using an AR-15 spring and i'll want the greater surface area to attach the original bolt piece. I know you said in the guide that the bolt side had to be trimmed to a quarter as well, but if the bolt is pulled back then it shouldn't interfere with the insertion of clip, correct?
Thanks in advance- Matt
Matt,
ReplyDeleteWell, if you want to do the "quarter-pipe" design, then both the bolt and barrel need to be cut in the same way.
This is because when the bolt is pulled back to open the breech, the guide on the bolt will be positioned directly over the clip feed section, so if its not a quarter pipe, the clip will still get stuck.
so does the length of the brass have to be different if this is to be done to the raider
ReplyDeleteattackthekid,
ReplyDeleteThe brass section measurements could differ slightly for the other reverse plunger blasters, so modders will need to test and make the necessary adjustments.
When adding the tightening rings onto the barrel, is there a risk of accidentally cutting the pipe? I was worried about this and it took me a few tries to get it right because the dart kept falling out of the front. How can you reduce the risk?
ReplyDeleteNaturalman_7,
ReplyDeleteWell, the trick to making tightening rings in the brass barrel is to only do shallow rotational cuts... stop cutting once you see the circular dents and the narrower diameter rings form inside the brass tube. Its all about trial and error.
If your foam darts are still loose even with tightening rings made in the brass barrel, then you'll have to change the size of the brass barrel or the size of the foam darts. :)
My last question is what type of pad works best? I've tried several and haven't been able to find a good one yet. Instead of buying all the pads and trying them all, is there a type of pad that works better? Gripper pads? Anti-slip, felt, bumper? I've tried some brands but most were too thick.
ReplyDeleteUnknown,
ReplyDeleteAny soft padding that can compress flat easily can work. Like i've mentioned, you have to test and see what works.
The common foam bumper material that hardware stores sell for cushioning furniture and table edges can be used.
Also try craft foam, they can be found easily at most art and craft shops.
If the padding is too thick, then just trim it thinner.
Thanks for your help.
ReplyDeleteWhich material do you think works best?
Unknown,
ReplyDeleteBoth foam bumper and craft foam work as well, they are usually made of similiar foam materials.
Do you need to keep the barrel attachment from the recon on? And where on the new brass barrel did you wrap it with tape?
ReplyDeleteSG Nerf,
ReplyDeleteI can't seem to do the barrel right. When I wrap the brass barrel with tape either the brass bolt hits it, the friction between the brass pushes the barrel out of the front, or when I try to position the brass barrel into the old one the tape just gets pushed out of the way. I'm not sure how to properly complete this part.
Unknown,
ReplyDeleteIts not necessary to use the front barrel attachment, the brass barrel lengths i use for Recons are usually less than 6 inches, which just fits within the main unit, 'cos if the barrel is any longer the performance tends to decrease and the foam darts sometimes even just get stuck due to lack of plunger air volume and power.
Naturalman_7,
ReplyDeleteSeems the tape you are using is abit weak or loose and slips off too easily, try using better quality electrical tape.
You need to keep testing various thickness of tape wrap around the brass barrel until it wedges securely inside the orange barrel.
SG Nerf,
ReplyDeleteIs there a secret I don't know? I bought 3M Scotch 33+ electrical tape and I still can't seem to be able to keep the barrel in place. Another thing is that there isn't a very large area to wrap the tape around. Any help would be appreciated.
Naturalman_7,
ReplyDeleteJust wrap the electrical tape in layers around the front section of the brass barrel and secure it properly. It requires some adjustment to get the fit just right.
i had a better idea for the breech. instead of inking three layers by hollowing out the punger. just sink the 1/2 and 17/32 width brass all the way into the plunger. by doing this the seal is much stronger and the greater shrink from one volume to another gives it more pressure. i would like your ideas on this
ReplyDeletecrakdice,
ReplyDeleteThat can be done too, but you have to make sure the alignment of the bolt and barrel are 100% perfectly aligned, as there would be no more extra tolerance of any variations in alignments (just a slight difference will restrict the movement of the bolt).
That's one of the reasons why modders do the brass breech with 2 layers of spacing, so that the priming movement is smoother.
I am confused as to where the piece from step 3 is supposed to go
ReplyDeleteUnknown,
ReplyDeleteThe brass tube section (with half-pipe and tightening rings) in Step 3 is the barrel for the brass breech, it is installed inside the existing plastic barrel. :)
My darts have trouble feeding and most of the time when I shoot the gun I get a slurping sound and the dart gets stuck in the barrel.
ReplyDeletecrakdice,
ReplyDeleteChambering issues could be due to your breech system not properly aligned with the clip, check and re-align if required. Shortening the foam darts slightly (ie. to 6cm length) could help too.
The stuck dart issue could be due to the breech system not being fully air tight, there could be some air leaks at certain sections, so you need to check the breech to barrel seal. It must have a 100% air seal.
Alternatively, it could also just be the barrel being too long and the foam dart getting stuck inside.
As mentioned in my guide, the Recon's reverse plunger air volume is small so it naturally doesn't have enough power to propel the foam dart through longer barrels (compared to other blasters with larger plunger volumes like the Longshot).
From my experience for a brass breeched Recon with 11kg load spring, i only use a 6" length brass barrel. If the barrel is longer, the foam darts would tend to get stuck halfway or fire out with reduced range.
Note that if you install springs with less strength, then you might have to use even shorter barrels due to the reduced power. Just try out various barrel lengths to find the optimal setup.
What would be the total cost of this mod?
ReplyDeleteNerf Modder,
DeleteWell, just the brass tubes for this mod costs around SGD$20+... not including the additional custom aftermarket spring, dremel, epoxy glue and various other tools to do the mod.
Hey SG Nerf, can the same dimensions be used for the alpha trooper? And EXACTLY which shop did u purchase the brass from? Thank you!
ReplyDeleteH3LL bOy,
DeleteThe same modding method applies to the Alpha Trooper, but the tube lengths might be slightly different, so you can take reference from the guide but will need to also re-check the fit and adjust if needed.
I get my brass tubes from NTC Engineering Hobbies at Fook Hai Building in Singapore.
Just curious, if I were to apply this breech to a Raider, should I use the same measurements and dimensions? Also, does a properly done brass breech achieve about the same performance as an aftermarket plunger such as the OMW kits?
ReplyDeleteBrian Lin,
DeleteYou could use the Recon measurements here as a guide.. but do re-measure the Raider internals to confirm and tweak the parts dimensions if necessary.
A properly made breech with 100% bolt to barrel seal should achieve better ranges than a stock breech (with equivalent mods).
But as mentioned in the guide, reverse plunger blasters have such small plunger volumes that they naturally don't have enough power to propel the foam darts through longer barrels anyways, so only the shorter barrel lengths can be used, which limit the overall range improvements.
100% bolt to barrel seal breeches work best with the larger plunger volume blasters.
The current OMW kits are basically replicated versions of the stock breech design (but made in polycarbonate), as there is no 100% seal between the bolt and barrel, the performance improvements would be based upon that of a stock breech system.