Upgrade an AUG A1.

[Iceni]

It's time. Time to start looking at the upgrades for my new AUG A1. I'm not new to the platform having been a user of the A3 for a long time.

I have a checklist of upgrades, Some have already been purchased, Some are going to be purchased and are still variables at this time.


So the upgrades I have ready to go.

SHS bore up kit. I don't need the bore up for volume but I wanted to try the better quality heads over the element set I have in the A3. So far I have these built on the desk and the airseal across the parts is fantastic.

Bushings, The A1 comes with bearings, but I'm going into the box so bushings in my mind are a more long term solution, that never collapse.

Downgraded spring,  The stock gun shoots at 400+ fps, so I have an m100 spring to go straight in.

Deans connections.

Full re-wire.


The variables are the parts I want help with.

I need to look at barrels. I don't want a tight bore in this gun. The A3 is setup on 6.03 and I wanted to go the other route. So what I'm looking for is a quality 6.05 or greater, In 500-510mm.

The current ones on the watch list are the PDI 6.05, Orga Magnus HD 6.13, Orga Magnus 6.23. I'm not sure about which one to pick.

Mosfet, I currently run a gate nanohard in the A3 it works well enough, I'm wondering if there is anything else I should look at.



The build I want to make is the silent, accurate type. The A3 I have does the RPS thing and is reasonable for accuracy but I want the a1 to be as accurate as possible. I have a few spare hops I can test so hops are not going to be a problem, and already know the platform well enough to get the most out of the basic body and the fitting of the gearbox to the hop.

 

[Davegolf]

You say you don't need the extra volume from a bore up kit but then say you want a 500mm barrel.

The max barrel length you can properly volume on an type 0 AEG cylinder is 430.

There are many great products that seal exceptionally in standard bore, just saying.

If you've already got the bore up kit then you may as well use it.

Id stay below 6.08 for barrel bore because of said volume issues.

Wide bore is best applied with gas or HPA.

Youre limited on mosfets for bullpup.

From previous experience I've  found the hardest part of making an accurate AUG is the hop unit to gearbox mating, it's hard to keep them both consistently in line so make sure to focus your efforts there for shot consistency/accuracy.

 

[Iceni]

You say you don't need the extra volume from a bore up kit but then say you want a 500mm barrel.

Stock on the AUG is 509mm, The volume ratio for them is always a little on aneamic side.

The ratio on the a3 I have is 2.09:1 I may attempt at some point to cut it back to about 480mm to see if that has a notable improvement on that barrel.

The a1 with the bore up and 500mm
6.05 = 2.33:1
6.13 = 2.27:1
6.23 = 2.20:1

Again I think getting the 500mm and perhaps thinking about cutting back if I had issues may be the way forwards there. I can then test at 1 length and evaluate it against the other gun I have that I know is right at the bottom of the ratio.
 

Youre limited on mosfets for bullpup.

I don't think you are anymore, Some of the longer plug and play type are a problem, But there is space on the AUG to make allowances for most fets. You have a whole heap of space at the side of the gearbox. I got the nano hard into the A3 without having to do anything special to the gun, The only issue was it has to go behind the backplate in a very specific orientation to fit. But that unit is wired as normal with a deans connector at either end. Certainly with a little foreplay I could get a larger unit into an AUG.


 

The max barrel length you can properly volume on an type 0 AEG cylinder is 430.

What ratio are you using for that? 2.50:1 Or as close as possible.

460mm with the bore up on 6.13 matches that ratio.

From previous experience I've  found the hardest part of making an accurate AUG is the hop unit to gearbox mating

There are a few tricks to that. The hop needs to be built right, bucking cut down, brass ring up to the bucking not the outer part of the hop (If the brass ring is in the wrong position it stops the hop moving fully backwards). The screws need filing back on the retention system so they don't catch the inner barrel, the plastic lugs on the outer barrel and hop need a bit of oil. The return spring needs stretching. Both sides of the hop spacer at the back of the hop need lapping flat (this also improves the distance the air nozzle can get into the hop), And the gearbox needs shimming on the backplate. Motor wires need to the as thin as possible (silver wire) and soldered in a way that doesn't impede the gearbox seat or push the box upwards. The magwell needs a shim at the front of the box to stop the hop moving forwards on mag insertion.

With the hop done right when you split the gun and rebuild it you can feel the hop moving as you engage the gearbox, and it's the hop spring that keeps everything tight and wobble free when the gun is back together. If you forget to file the inside of the hop spacer this is the point you notice you can't adjust the hop!

Do all that and the gun shoots without a problem and splits/rebuilds without issue. It's more of a tolerance thing with AUGs remove the play correctly and they work well. You simply mod the assembly so it can only fit together in the best possible way. It's not a complicated set of mods, The hardest part with them is knowing where to start. I was lucky with mine because one of the old boys at my local site is an AUG lover, and he took me through his mod method to get them working well.

 

[Davegolf]

In all my testing at AEG power levels I've found no benefit to running longer than 430mm.

Accuracy gains plateau from there, as before if you've got the bore up then use it for filling the A1 outer barrel with inner.

Likewise widebore on AEG isn't beneficial.

430 on a full non AOE cylinder is 2.19

In that ballpark;

Lower ratio than that will adversely affect the energy potential of heavy BB's.

Higher ratio will make more noise.

What I meant by limited MOSFETs wasn't space or size but drop in options like BTC & Titan.

Thats good that you have past experience of the extra efforts needed on the hop unit over more common place AEG platforms and aware it's more difficult to get consistency from.