[Lightf4ng]

I've read the effects of weighting a vsr piston and has done it myself by wrapping lead tape on my piston. I have also seen and used edgi vsr bore up kit and how it reached up to 6J compared to stock cylinders. I now have a arcturus ak12 coming and was disappointed to know that it won't come with full cylinder despite the 450 mm barrel that comes with it. I'm thinking about adding lead tape inside the walls of the piston and installing a bore up kit with it. What are the best ways to go about adding weight aside from sticking lead tape inside the piston? I also prefer doing it without using methods such as melting lead to make weight thus compressing the spring. Thanks in advance

 

[Lightf4ng]

I think that I've seen a steel piston before, and a steel piston head, so I'd look into that.

@1tonne has more experience with high powered AEGs than I do though.

Yeah it's kinda hard to do this project but i will still try. I saw a post that they inserted an inner barrel with an extended screw from the piston then added the weight there. Tbh m150 is not considered high powered here except from cqb arenas

 

[Lightf4ng]

I had a full metal piston way back in the day, I believe it may have been Lonex or possibly Guarder. I do know Lonex makes them. along with piston heads and so forth - actually very reasonably priced. I wouldn't necessarily bother with a bore-up kit, just change to a full cylinder.

One point to mention, the Lonex is definitely aluminium and very light so it may not be what you're looking for.
@Lightf4ng - are you trying to get as much power as possible out of your setup? 1Tonne or Cripplegunner have more experience with AEGs over 2.3j, mine ends there.

Yes I plan to maximize power with not much of a strong spring with guarder bore up kit, nylon piston, and guarder sp140 or sp150. On my full cylinder m4, and 30 g stock piston/head I got 2.62J with .2s up to .36 on stock 6.01 363 mm barrel and 2.4J on .20 to .30 bb.

 

[Lightf4ng]

The heaviest available nylon piston with metal teeth in my country is around 20g. The piston head is around 10 g. I don't like mix and match compression parts but I might go that road with the piston only for the guarder bore up kit that I plan to use tho since there's no available piston included with the set. However, this project might not push through due to the new Arcturus AK12's proprietary hop unit (it's the first time I've seen a rotary hop unit for AK).

 

[Lightf4ng]

Begadi and Combat Union make rotary hops, very well regarded.

Such brands don't have products here in our country. 95% of AKs here are by LCT.

 

[Lightf4ng]

Most players using carbine style rifles outdoors (in my experience), tend to use .25 to .28 gram BBs, for which a partially ported cylinder is in the realm of okay.

However, I do have experience using full cylinders to obtain higher power, especially making use of joule creep. I suggest staying the heck away from metal pistons. Occasionally I’ll see a cylinder and cylinder head that are a bad fit, and cause rubbing, and the result is no good. Metal pistons basically,y automatically cause rubbing and issues, and from my research almost always end in total failure, since aluminum is very soft.

If you want to beef up your piston weight, go for an aluminum piston head, a thick polymer piston like the Lonex red, or another heavy piston using a full metal rack, which can have some advantages, and keep the bearings on the piston head to add about 8 grams just for those. For this level of energy, you’ll need a very beefy piston assembly anyways.

Thanks for this. I have decided to use a steel ribbed cylinder, polymer piston with metal teeth and lead tape inside, and aluminum head with bearings (total weight of 35g). Barrel is stock 380 mm 6.02 made from steel. All compression parts will be replaced except the stock nozzle. Bucking is stock, (black copy of G&G) and I replaced the nub (too soft) with a maple leaf omega. Overhops .36 with just a few mm of turns on the stock cylinder and spring. Will post results soon

 

[Lightf4ng]

I get pretty darn good joule creep out of a 31 gram piston assembly. Be careful when going too heavy as the piston will start to experience more lag than normal during acceleration, and cause a weird pressure wave.

I speculate that it could even throw off your hop settings and consistency, due to the BB experiencing less immediate acceleration, and rather gaining more energy farther down the barrel.

I don’t know if any of these effects are strong enough to be relevant at all with your setup, but I thought I’d throw the ideas out there.

There is a thread here on this site with results for different weights on VSR pistons, but VSR and AEGs don’t usually correlate directly…

My guess is that spring weight factors in to the total weight of the piston and head as well since it still in contact with the head. I think 30-35 g weight is not that heavy but more jc would come from a really short barrel.

 

[Lightf4ng]

Hi, Sorry to jump in,
is piston weigh really add something to joule creep or fps gain/loose? Any experiment done?

I was thinking that 20gr or 40gr piston will get same effect, as most work to push/compress the air comes from the spring tension/energy and that 20gr difference on the piston will be negligible to this spring tension/energy.
With this piston weight double I was thinking about the double momentum tho, but again when thinking about the spring tension it void my thought.

CMIIW

I don't have the exact science how this works but my understanding is that it allows overvolumed set ups to get the maximum energy from the compression (the end of the air/pressure wave). Search piston weight in the forum and you'll find @1tonne's explanation with it. The concept is solid but results may vary depending on the set up and mods due to a lot of factors like volume, spring strength, bb weight, air leak, hop, etc. The only thing we can do is to mod it until you lose energy.

 

[Lightf4ng]

I got guarder SP130 spring, 6.03x363mm inner barrel, full cylinder with volume calculated just like your pinned post. I get 2,4 joule with 0.4g bls bb. Fps variation within 1 fps. In your opinion do I need to add some weight?

I am pretty sure my piston set up is really light, shs blue holed piston and shs polymer (red) piston head.

Let us know if you did mod this more. 🙂