Is it really necessary to upgrade recoil spring guide, hammer springs when getting a metal slide?

[Honzo]

I know all these things such as recoil spring guide, upgraded hammer spring, etc are used to upgrade the performance of the kick or FPS of the GBB. I'm getting a tokyo marui g18c and I'm just planning on slapping a shooter design slide on it. Do I really need to upgrade anything else? will my pistol be less durable if I just stick with the metal slide and barrel and dont opt for the recoil spring or hammer spring? I will be using green gas on it.

[steaktipz]

No durability concerns, but you might need the stronger hammer spring to give the slide a little more power to complete a full cycle. Or you might not. Go ahead and buy the slide and see how it shoots, if it works you don't need anything else.

[Honzo]

Thanks! any other inputs? I'm sure a lot of people here are very very knowledgeable about gas blowbacks!!!

[mimesis]

OK, yes, can I jump on board with a related question?

 

If you have an upgraded hammer spring, the hammer will hit harder the bit that in turn hits the back of the flow valve. But does this actually allow more gas to escape per shot? Once the central little piece in the valve is pressed down flush with the circular bit around it (sorry for the lack of terminology), it can't go any further, right? So does the upgraded hammer spring actually make for a snappier response time rather than for more gas.

 

Microseconds later, as the slide is being propelled backwards, the main thing it encounters on its journey backwards--and its main function in doing this--is to press the hammer back down. If the hammer is on a firmer spring, won't the slide have a harder time pressing the hammer down? So doesn't a firmer spring actually impede the cycling of the slide?

 

In other words, is not what is gained from the firmer spring when the hammer is moving forward (shooting) not then immediately afterwards lost when it's moving back again (recocking)?

 

Or am I missing something?

[Yuri]

If the hammer is on a firmer spring, won't the slide have a harder time pressing the hammer down? So doesn't a firmer spring actually impede the cycling of the slide?

 

I think this is spot on. There is some optimal hammer spring strength that's enough to open the valve and keep it open without being too hard to cock, and I bet the spring Marui put in there is precicely this. The valve knocker will be locked in place where it holds the valve open and released when the slide moves back, and it seems to me that the only reason you'd need a stronger hammer spring would be if the gas pressure was somehow higher.

 

Also, I recently bought and upgraded a Marui Glock 17 and during my pre-purchase research, I found the general consensus online to be that a stronger hammer spring in this gun specifically is useless. I did buy a stronger recoil spring, but haven't installed it because the action seems snappy enough without it.

[BaBaBooey]

In my opinion, you want to leave the pistol, especially a new Marui, as close to stock as possible. Assuming your pistol is a backup, you want to make sure it's going to be as reliable as possible; I found that recent Marui pistols (ie. PX4) have been most reliable with all the original parts. Even a simple upgrade like a metal slide can increase the likelihood that the pistol will fail when you really need it. Upgrades to increase the FPS will even increase the probability of failure even higher.

 

Hitting a magazine valve harder will NOT allow more gas to escape. However, slowing down the slide with a stronger recoil and hammer spring will delay the valve knocker lock from engaging causing more vaporization. You may initially get higher power, but the result of this is a measurable decrease in efficiency. Since there is more vaporization, more heat is exchanged causing faster cool down. With more cool down, you begin to loose more power as you fire the bb's. To counter this, you upgrade more and you are eventually stuck in an endless loop of upgrades. Then you try to use the same pistol on a cold day and it may not work at all.

 

Again, you want something reliable as your back up, keep using the original parts. Make sure you chrono it so its output is within the recommended range - if it's too high or too low, change the propellant you are using instead of trying to upgrade it.

[mimesis]

Thanks for the explanation. This all makes perfect sense.

 

I wonder what you would recommend if someone were into the more, er..., aesthetic side of things, and definitely wanted to put on an after-market metal slide.

 

Trying to think it through, it seems like swings and roundabouts to me.

 

If you install a fimer recoil spring and a firmer hammer spring, the slide will start to move backwards more slowly than it would otherwise do, thus letting the valve stay open for a bit longer and releasing more propellant tp help the BBU push the slide back. On the other hand, as they are compressed, both firmer springs are mechanically putting up more resistance to the backward motion of the slide. At this point, it seems like the one is cancelling out the other, and you might as well leave the stock springs in there.

 

However, if and when the slide reaches its backmost point, the compressed recoil spring will then snap it back into battery; if the slide is heavier (metal), it will need a more powerful spring for it to return to battery as fast as a plastic slide would with a stock spring. Right?

[BaBaBooey]

From my expereince, I never had a metal slide that was so heavy, it could not properly cycle to chamber the next BB with the stock spring (I have never used a steel slide). A stronger spring may apply more stress on the cylinder as it returns, which might weaken everything from the hop chamber down to the magazine gasket. Then you start buying more upgrades. You think you got the perfectly upgraded pistol and then it stops working as soon as the temperature gets slightly colder.

 

This is the same for a metal slide. It looks better, but you have to be willing to live with a possible impact to other performance factors (again, if it's your backup, you need to make it as reliable as possible and that's usually a well maintained stock gun with all the original parts). What factors a metal slide impacts is very difficult to say. Remeber that the performance of a liquid charged pistols is almost always dependent on the temperature you typically use it in.

[Simo_Hayha]

I have seen two metal slide tm g17s break the rear sight as a result of using green gas and a stock recoil spring. The slide whacks backwards so hard that it can break the sight.

 

Actually, I've seen hicapas do the same thing, and the problem was always remedied with a 150% recoil spring. It balances out the increases recoil, so to speak.

[Kalashnikov_kid]

I tend to high flow the mag valves on metal slided guns, but only double stack ones.

 

I find the ONLY time you need a stronger hammer spring is if your light striking the mag valves. CO2 mags do this a lot.