Airsoft Sniper Forum banner

Bolt Won't Lock With Stronger Spring

1151 Views 8 Replies 5 Participants Last post by  dschmidt
Hey everyone,

TL;DR: Toy works as expected with the stock spring however won't lock the piston with a new AA M170 spring.

Just got into the fields and have the ASG M40A3 Sportline as my starter weapon, thanks to @T4nkcommander 's beauty of a thread I was able to do good work on it with a new barrel and the AA Chamber.

Also got an AA M170 spring however when installed that spring the bolt just won't lock no matter how hard I pull the thing(tis quite harder to pull with that installed), when this first happened I almost soiled myself thinking that I broke or damaged the sear since I have quite the limited access to spare parts. But when I installed back the stock spring, it just works. I made the switch between them a bunch of times to maybe figure out what was causing it but no luck.

So any insight at all would be greatly appreciated.
  • Like
Reactions: 1
1 - 9 of 9 Posts
It’s probably a thicker coiled spring and/or longer when it’s fully compressed. If it’s longer, no matter what you do, it won’t latch because it’s preventing the piston from reaching the sear. I’d try clipping a coil at a time.
Hey everyone,

TL;DR: Toy works as expected with the stock spring however won't lock the piston with a new AA M170 spring.

Just got into the fields and have the ASG M40A3 Sportline as my starter weapon, thanks to @T4nkcommander 's beauty of a thread I was able to do good work on it with a new barrel and the AA Chamber.

Also got an AA M170 spring however when installed that spring the bolt just won't lock no matter how hard I pull the thing(tis quite harder to pull with that installed), when this first happened I almost soiled myself thinking that I broke or damaged the sear since I have quite the limited access to spare parts. But when I installed back the stock spring, it just works. I made the switch between them a bunch of times to maybe figure out what was causing it but no luck.

So any insight at all would be greatly appreciated.
Unfortunately, you've just found out why it is [seemingly] impossible to get more power out of the gun. The problem is the chamber is APS2, but only 11mm OD springs (VSR spec) fit due to the proprietary piston. Since VSR10 springs are longer by default - and scale up in length concurrent with power - you get to the point where the piston refuses to engage the sear.

The only workarounds I can think of are either to 1) buy an APS2 13mm ID piston and shave it down from 90deg to 45 deg, then buy a 13mm OD spring (such as a Novritsch SSG spring) and use it, or 2) find a 11mm OD spring that is APS2 length so that the sear still engages.

I have not been able to do #2, and I don't particularly want to bother with #1 until I have a few more confirmations it works.
It’s probably a thicker coiled spring and/or longer when it’s fully compressed. If it’s longer, no matter what you do, it won’t latch because it’s preventing the piston from reaching the sear. I’d try clipping a coil at a time.
From both of your responses I gather that this is the case. However clipping probably won't be an option because weirdly enough while having thicker coils and being longer when compressed, when uncompressed the spring is a tad shorter than the stock one. So probably if I clip enough coils to save the compressed length, I won't be able to use it because of the uncompressed length.

The only workarounds I can think of are either to 1) buy an APS2 13mm ID piston and shave it down from 90deg to 45 deg, then buy a 13mm OD spring (such as a Novritsch SSG spring) and use it, or 2) find a 11mm OD spring that is APS2 length so that the sear still engages.
I remember you mentioning that an L96 sear fits the trigger assembly in your upgrade thread, wouldn't that be a 90 degree sear? So wouldn't a third option be getting a 13mm piston along with a 90 degree sear? That sounds possible to me and my newly acquired and limited understanding of how the sear/piston degrees work, so please correct me if I'm wildly wrong here :hehe:
Ideally you'd be able to make a new trigger and use an APS2 piston.

As you can see, the weird one is very ghetto and probably not insanely hard to make, just needing a hacksaw, file, and drill.

This chap also 3D printed a trigger, making only one or two parts out of hacksawed and filed steel, so this is also very doable if you have a friend with a printer and somewhat basic design editing skills to make the trigger function in your gun.

Bumper Automotive exterior Handgun holster Wood Gun accessory

Font Automotive tire Electronic component Auto part Automotive exterior

Wood Electric blue Hardwood Wood stain Rectangle

Font Musical instrument accessory Cable Metal Rectangle
See less See more
4
The whole trigger assembly (which is 45 degrees) is not something i've messed with much, outside of a replacement sear (which was also 45 degrees). Not even convinced this is necessary, as it was the sear housing that broke on my last 45 degree gun, not the sear itself. Anyway, there's a facebook group for the gun that I'm told is a good resource - apparently a few of them have made some progress on the trigger assembly. I long ago removed myself from the cesspool that is facebook, so I cannot say for certain what strides the group has made on the gun.

Converting a gun from 45 degrees to 90 degrees is a substantial overhaul. If the facebook group has figured out how to do this, then that would be the ideal path to take. 90 conversion -> 90 deg APS2 pistion -> 13mm OD APS2 spring. If one could get that setup working you'd have THE budget sleeper.

The reason the piston is proprietary is because ASG/Double Eagle used a 45 degree setup with an APS2 chamber - this required a custom piston, as APS2 systems are 90 deg standard. Because of this you get the negatives of both systems with none of the positives. Well, the cost savings is pretty substantial, and allows the gun to be cheap but perform pretty solidly out of the box. It is a great entry rifle for this reason, but be careful before spending a lot of money upgrading it that you are sure to get results. I only spent about $200 total on my gun - not including numerous hours of my precious time - even so, it shoots the same now as it did stock.

The important thing is to increase power, as everything else follows. Check out that fb group and report back - I'd be curious as to if anyone has their gun shooting 2.8J or above.
See less See more
  • Like
Reactions: 1
Well guys I jumped ship :D

Found a guy selling some mix of JG, TM and upgraded VSR parts(basically a full gun, just disassembled and possibly missing a couple screws) for 50 bucks, decided to get that and move my AA hop chamber along with the new barrel to that and build upon that. Also will move the original TM hop chamber to the M40 to keep as a backup or possibly even sell.

That story aside thank you for the immense help you guys sent my way and sorry to disappoint by taking the easy way out but hey at least it's one more google search result for the future ASG Sportline owner.

It is a great entry rifle for this reason, but be careful before spending a lot of money upgrading it that you are sure to get results.
I think this was the bottom line here, after spending more than what I got the gun for and not seeing that substantial of an improvement along with the not being able to up the power unless I get into some overwhelming(at least for me) DIY solutions; jumping ship especially for this cheap and being able to recycle my already spent money seemed way too good to pass. Not to mention that VSR parts are veery easy to find whilst anything else is near impossible to find around here. I will miss the cheek rest though.
See less See more
For me when I very briefly played with the M40A3, I removed the cheek rest as the screws poked into my cheek while not wearing a mask, and while wearing a mask I would have to tilt my head uncomfortably far over to look through the scope.
I had decent height rings and various scopes, but I would not be particularly sad about losing the riser.
That being said, maybe you have a different setup somehow, don't wear a mesh mask, or have better suited facial structure for the gun, but I've found it to be one of the more uncomfortable stocks I've used of the 25+ firearms, airguns, and of course airsoft guns I've held and shouldered.

I did like the look though, so for a while when I used VSRs I had this stock I modified to vaguely look like an M40A3
Bedrock Wood Trunk Road surface Tints and shades
See less See more
  • Like
Reactions: 1
Sweet Jeezuz, I'm so jealous of you guys back home that have access to all the parts you could ever need. All the best to ya!!
1 - 9 of 9 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top