TM Glock 18C cycling issue

[The Lord Tea]

Howdy all,

I’ve recently acquired a decent TM Glock 18c 

It has a Guarder lower, return spring and hammer spring - 150% I think. I’m not sure about the trigger parts and valve knocker to be honest. 

It also sports an Airsoft Surgeon metal slide. 

Fires beautifully, however, it doesn’t cycle right. The slide only just kicks back enough to chamber the next round so I t never travels back far enough to ensure it locks back after the final round.

Rack the slide manually with an empty mag in and it locks fine. 

Using green gas on it - white is too weak. Have tried theee different mags and all give the same result. 

Am I using too high powered a hammer spring? I’ve ordered a stock replacement

Any ideas would be appreciated  

 

[SCAR_Jester]

Probably the 150% spring combo, you don't need more than a 120% hammer spring unless you live in very hot countries.
Make sure the slide has little to no friction against the frame also (best check is remove all slide parts and slowly rack by hand).

The stronger the recoil spring the quicker the return time starts, so with such a strong spring and heavy slide, it's possible that is partly the reason but I think it's mostly the hammer spring.

Try the stock one with a bb under it (trust me) and see how it goes.

 

[The Lord Tea]

A BB under the mag spring do you mean? Tried that - put up to 4 in to no avail! ? I’m hoping to be able to fit a stock hammer spring tomorrow night. 

Moving it slowly as you’ve suggested, it seems to snag really badly on the “rocker” (for want of a better word) on the hammer. Reluctant to take a file to it though, as pressure on there is what sets the sear! ?

 

[SCAR_Jester]

A BB under the mag spring do you mean? Tried that - put up to 4 in to no avail! ? I’m hoping to be able to fit a stock hammer spring tomorrow night. 

Moving it slowly as you’ve suggested, it seems to snag really badly on the “rocker” (for want of a better word) on the hammer. Reluctant to take a file to it though, as pressure on there is what sets the sear! ?

1 BB with the Stock hammer spring (the one in the grip) should act like a 120% which is perfect.
The 150% may be a little strong for green gas but should still work.

The BBU always hits parts of the frame, which is why you take it apart entirely (all the slide parts), then try doing it without a spring most importantly.
If it rubs on the frame (nothing else) then the frame should be extremely lightly sanded/lapped.

 

[proffrink]

Try the stock return/recoil spring but I'd keep the 150% hammer spring as it's useful for more consistent release of higher pressure gasses. Sorry for stating the obvious, but make sure you're filling your mags properly (i.e. upside down) and are using a reasonably strong green gas. I use a 150% recoil spring in my G18C and have no issues, but I'm using a Guarder slide.

If that all fails, you may have to polish the slide itself with a Dremel. Also look at doing the same to the rails on the frame/chassis. Make sure it's well lubed on the rails too of course. The litmus test for this though is just seeing if it manually cycles. It should return fully to battery even after dropping the slide when it's locked back with the slide lock. If it's not able to do this (or stops 1-2mm short as it hits the hammer) then polishing the top of the hammer itself can help too if this is a new donor gun. I've found the TM G18C hammers sit quite high up (compared to the 17) and do take a bit of break in (around 600 shots) before they stop grinding against the bottom of the blow back unit.

 

[Guest]

1 BB with the Stock hammer spring (the one in the grip) should act like a 120% which is perfect.
The 150% may be a little strong for green gas but should still work.

The BBU always hits parts of the frame, which is why you take it apart entirely (all the slide parts), then try doing it without a spring most importantly.
If it rubs on the frame (nothing else) then the frame should be extremely lightly sanded/lapped.

Hammer spring in the grip?

 

[proffrink]

Got his 1911s and Glocks muddled up I imagine

 

[SCAR_Jester]

Got his 1911s and Glocks muddled up I imagine

Yes! Been working on my Hicap all morning haha

 

[Guest]

Any ideas would be appreciated  

I’ve  built tens of Glocks, mostly TM’s

Without more work than you can justify, you won’t get all those different manufacturers parts working well together, tolerances vary between manufacturers, just enough to appear identical, but be different enough to mess things up.

If you have all of the original parts, go back to a completely stock pistol.

Change one thing at a time until you hit the problem.

I think it’s almost my certainly a mismatch between one manufacturers frame and another’s slide

rdb

 

[proffrink]

Uhm, if you've built loads of Glocks then hopefully we're in agreement that the rails the slide travels on aren't part of the Guarder frame (and are TM stock chassis)? I can certainly agree with some slides being hit and miss though. Would suggest a polish, but again this can be easily diagnosed by cycling it manually a bit. That would quickly rule out the recoil and hammer springs as an issue. Never had an issue with Guarder frames but I've only had 4 of them so perhaps a bad batch? If the frame itself was sitting proud I feel this would be very obvious. The slide of course should sit about .5mm higher than it.

 

[Guest]

No, but how the rails sit in the frame does make a difference.

For example, no matter what spacers or different make inner frames I tried, I could not get Ace1Arms RMR SAI slide cycle on a GunsModify frame.

Both worked fine with standard components baring heavier springs, but refused to work together.

I now run a pretty standard TM G22, barring a few springs and Maple Leaf doo-dads lol

 

[The Lord Tea]

Given it a quick polish with the ol’ Dremel. The action is less Grundy, but a sticking point really does seem as though it’s either the recoil spring or the hammer spring, but I more suspect the hammer

New hammer spring part arrives tomorrow, and recoil spring the day after. I’ll let you know how it fares after that. 

 

[The Lord Tea]

Okay so new (stock) hammer spring plus 150% recoil spring turns it into a “single shot” pistol is: needs cocking after every round!!!

weaker recoil spring on the way. Will try that with the harder hammer spring - I’m hoping that will be the winner! 

 

[SCAR_Jester]

Okay so new (stock) hammer spring plus 150% recoil spring turns it into a “single shot” pistol is: needs cocking after every round!!!

weaker recoil spring on the way. Will try that with the harder hammer spring - I’m hoping that will be the winner! 

Do you know if the slide is going back far enough to actuate the hammer fully or is it perhaps only cycling slightly? (this may be hard to see as manually racking you will likely be able to pull it the whole way).

 

[The Lord Tea]

I don’t think it is. Towards the end of the mag it goes into full auto itself, if that makes any sense!

 

[SCAR_Jester]

I don’t think it is. Towards the end of the mag it goes into full auto itself, if that makes any sense!

I have a theory, you have a magic gun.

 

[The Lord Tea]

Thanks Corky... ? I wish it would use some of that magic to sort itself out. Losing the will to live a bit lol

 

[The Lord Tea]

By full auto - I mean as in it splutters and does lots of little short slide cycles 

 

[proffrink]

Is this with or without a 150% hammer spring and a 120% recoil spring?

 

[The Lord Tea]

Stock hammer spring, 150% recoil spring