Jump to content

Archived

This topic is now archived and is closed to further replies.

DangerWerx

XCR Escort Engine Project; Drop-in, Progress and Pics

Recommended Posts

Hey Guys, 

 

I wanted to start off by saying I love gas guns, classics in particular. One classic airsoft engine that I have come to love is the Escort platform. I was blessed to fall into an odd airsoft group in southern California that fabricates some amazing Escort based projects. Their influence has rubbed off on me and I have decided to try my own at getting an engine up and running. 

 

The engine is based off of the original Escort Mp5 with modifications to fit into the receiver. 

 

I chose the XCR model as a based because of several reasons

- Feed system is built into body ( easy chamber alignment )

- Not an M4, takes M4 mags

- Easy to disassembly

- Strong barrel mounting points, can take a beating

 

Deviations from Mp5 engine

- Aeg compatible barrel

- Redesigned Chamber (for barrel/hop)

 

The first iteration looked like so...

pvgxd3q.jpg

 

Parts are

Chamber - peach

Blue - Bolt

Bolt Carrier- Pink 

Spring Guide - Yellow

 

Next Iteration of the Design

vS6ugKm.jpg

 

Changed from a Bolt Carrier design to a Bolt guide for easier manufacture. Added items too

 

 

Chamber - Peach

Bolt - Blue

Bolt Guide - Pink 

Spring Guide - Yellow

Nozzle - Purple

Transfer Valve - Green

 

Once I was confident in the design of the parts, I had initial fitment parts 3d printed.

 

The printed test parts, chamber, bolt and bolt guide

wt0T0yu.jpg

 

They turned out much better than anticipated. Strong with a 100% infill, I have no doubt these parts can take a beating.

 

Here they are installed onto the XCR barrel

aI1A0wQ.jpg

 

Bolt and Bolt guide in the upper receiver

QRAAXZk.jpg

 

And here is a view of the chamber and bolt in the upper receiver

BPO5mio.jpg

 

We are now mapping out the lower receiver and designing a fire control group to work with the selector. 

I am leaning to the Escort Mp5's method of a semi and auto lever engaging a contact plate. 

 

I'll post more info once we hit another milestone.

 

- Dave

 

 

 

 

 

Share this post


Link to post
Share on other sites

looks really cool. if it would help, you can contact tony rizzo at tnkgunz.com. he's the american distributor for daytonagun.

 

Thanks, I'm good though. 

I have a good set of mentors who are knowledgeable in Escort engines. One used to work for Mr. Tawada.

Share this post


Link to post
Share on other sites

I've thought about scratch building an escort engine as well so I'll be watching this with interest. Are the 3D printed parts just for mock-up, or are you going to use them in the final assembly?

Share this post


Link to post
Share on other sites

I've thought about scratch building an escort engine as well so I'll be watching this with interest. Are the 3D printed parts just for mock-up, or are you going to use them in the final assembly?

They are a mock up. 

Cutting chambers and bolts take too much time to cut. Dedicating a whole day for a chamber was not appealing. So the major points that mount inside the receiver were printed first to make sure our dimensions were right. We will probably have to 3d print the subchambers though. 

 

 

Looks lovely, may I ask what model printer your using? And if that's ABS or PLA? It looks like PLA but thought I'd ask :-)

 

I actually used a local firm to have them UV-Resin printed. Polyjet Verowhite to be exact. the stuff is extremely durable and machines easily. Gums up composites though.

 

I had my time with Makerbots and a few repraps, they can produce great stuff if you babysit and have a few tries. Newer gen machines are looking go though, particularly the Series A Type 1 Machine.

Share this post


Link to post
Share on other sites

There are multiple reciprocating or 'rod' seals in an Escort engine where different parts seal against the nozzle. A couple in the transfer valve, one inside bolt and possibly one more in the chamber. Once you get around to those parts, I would be very grateful if you could give some critical dimensions. What size O-rings you end up using, depth of O-ring grooves etc. Also what sort of tooling you use to cut the O-ring grooves.

 

The sealing of the chamber puzzles me. The Escort engine fires at a point where the nozzle is already moving backwards for a reload. Because of this, it doesn't seem like the lips of the hop rubber will be enough to form a seal like they do in an AEG. So an additional rod seal must be placed inside the chamber, but it seems like it would be difficult to cut. You'd need a fairly long and thin boring bar.

Share this post


Link to post
Share on other sites

current daytonaguns use a long hop up rubber. the lips are essentially an inch long. long enough so the nozzle stays sealed until the BB leaves the barrel.

Share this post


Link to post
Share on other sites

There are multiple reciprocating or 'rod' seals in an Escort engine where different parts seal against the nozzle. A couple in the transfer valve, one inside bolt and possibly one more in the chamber. Once you get around to those parts, I would be very grateful if you could give some critical dimensions. What size O-rings you end up using, depth of O-ring grooves etc. Also what sort of tooling you use to cut the O-ring grooves.

 

The sealing of the chamber puzzles me. The Escort engine fires at a point where the nozzle is already moving backwards for a reload. Because of this, it doesn't seem like the lips of the hop rubber will be enough to form a seal like they do in an AEG. So an additional rod seal must be placed inside the chamber, but it seems like it would be difficult to cut. You'd need a fairly long and thin boring bar.

 

Sure thing.  

You are right on the rod seals. I have no problems letting ya know which O-rings to use, they are mostly lifted from the Mp5. I'll probably be a little more tight lipped on other dimensions. 

 

The nozzle of the Engine actually sits pretty deep into the hop up rubber. It is more akin to a vsr-10 hop up rubber than it does an AEG. Both the VSR-10 and Escorts fire from a close bolt position than  the usual AEG's open position

Share this post


Link to post
Share on other sites

Ah, I get it now. I thought daytonagun was using an AEG rubber but it only looks similar from the outside. That makes sense.

Share this post


Link to post
Share on other sites

Ah, I get it now. I thought daytonagun was using an AEG rubber but it only looks similar from the outside. That makes sense.

Yea. 

 

He has casted his own hop rubbers.

We will be casting our own since we do not want to be tied to DG's supply. 

Share this post


Link to post
Share on other sites

One way I think you should improve/differentiate from current Escort engine variants would be to add a hammerish action that deals with the valve button. Sort of like any GIM GBBR works except instead knocking valve knocker the hammer just pushes the shooting valve open.

 

What do you think about this?

Share this post


Link to post
Share on other sites

We've thought about it.

 

Don't think it will be too efficient considering the location of the transfer valve and engine's need for a steady stream of gas, instead of a quick burst. The Escort engine's disconnector is really good for timing issues in that regard.

 

the location of the hammer in relation to the transfer valve would mean a longer receiver is needed to work. The mp5 engine is pretty much the shortest engine you can go for most projects ( have 1/2 inch remaining for the XCR engine)

 

What do I feel is an easier attempt at using a hammer design would be the old Brass Eagle Nightmare valve or the current KWA NS2 cylinder. Both systems have better provisions for a bolt to recock the hammer. Both can be machined by hobby machinists. 

Share this post


Link to post
Share on other sites

Still working on it.   

 

Since my first post, we figured out how to mount an aeg pistol grip and the general locations of the trigger (aps M4) and the rough areas where the levers will go. Waiting on Echo1 to restock selector switches to get that squared away.

 

We've had to change the chamber design as well as the bolt. Having a 2 stage bolt delay was giving us headaches. 

 

Should see first steel prototype bits in the coming month. 

Share this post


Link to post
Share on other sites

Just a quick update. 

 

We have machined some of the parts in steel.

 

Makes a very satisfying PING when the bolt slams into the Chamber

 

XL9OAuL.jpg

 

yCHUCHX.jpg

 

The Chamber, bolt, bolt guide, spring guide and selector are now steel.

 

Will change the bolt guide pretty soon, away from the bullet design towards a simple bushing for smoother action.  

  

Spring used is from my DG AK High-Rate Spring (Coming Soon)

Share this post


Link to post
Share on other sites

Excellent.

 

Please keep the updates coming, this is a genuinely interesting and alternative project, and you're making the parts properly. What more could I ask for?!

Share this post


Link to post
Share on other sites

Looks awesome. Will you make the transfer valve out of steel as well? Usually they seem to be either brass or aluminium and I've wondered if they get beat up by the steel parts. 

 

Is there a feeding tube built into the lower receiver that will direct the BBs into that hole in the bottom of the chamber?

 

Is the piece with the o-rings held in place by just the nozzle tube passing trough it?

Share this post


Link to post
Share on other sites

Getting hop up Rubber molds finalized. The XCR and a few other pipe projects ( I am on pre-order for that A&K MG42) are on hold until we can get the hop up rubber squared away. 

 

We don't want to be tied to DG's supply.

Share this post


Link to post
Share on other sites

Hop-Mold Pins

 

DiaHCWo.jpg

 

IrmEy1o.jpg

 

Q3Hu2ZH.jpg

 

These Have been sent off for prototyping. The level of detail is too much for our manual machining ability.

 

We'll have a pair of rubbers cast for testing in our projects (XCR, Stens, ???) as well as a few DG AK's and M249

Share this post


Link to post
Share on other sites

×

Important Information

By using this site, you agree to our Terms of Use and the use of session cookies.