Is it possible fix the crazy gas consumption of my TM 1911?
 

The Story:
I've had my TM 1911 for around 4 seasons now and the plastic slide was getting beat up and worn down. It was still functioning wonderfully as TM is known to do but it was a bit of a gas hog. I was aware that if I installed a full metal kit it would get even less shots off then usual but I didn't realize it would be cut down by this much. After installing the kit the shots i was able to get off on a magazine full of gas went from around 20 to 7. Yes, that's right, 7. Now I enjoy realism but this is not practical at all for APSC or even pistol games. Is there anyway to fix this crazy of gas consumption?

Note: I also should have added that It has a 150% spring installed which I realize would knock the gas consumption way up but if I put the other spring in I'm afraid the pistol won't cycle correctly. Any one have any ideas?

Change out your piston head, it's probably pretty worn out.... same with most parts in the blow back housing...

possibly change out the seals on the top of the mag, all the gas may not be getting into the housing..

You can try using the stock spring as well. I used the stock spring in my Hicapa with a Shooters Design metal slide and it still cycled perfectly, just the kick was reduced. And gas consumption went up.

Other than that, yeah try and get some better or new compression parts (loading nozzle, piston head, etc).

Thanks a lot. I was looking around at Illusion's stock and am considering installing a few parts when I get some cash.

Are there any warning signs of a warn piston I should be looking for or do I have to take apart the blow back unit once again?

True that. Try your stock springs before you do anything else. A stock recoil spring (lighter tension than aftermarket kits) will give you MORE kick but LESS gas usage. A stock hammer spring will give you LESS consistent valve strikes, meaning LESS kick, LESS velocity, but only slightly less gas usage. Personally, I have a number of extra recoil springs as I only install hammer springs from spring kits in my pistols. Lesson learned from my first GBB (a WE single stacker) and subsequent tinkering - a stronger recoil spring will reduce gas consumption from 18 quickly fired shots to 8.

Not true. Piston head (unless it is cracked) will do nothing for your gas CONSUMPTION, it will only improve the efficiency of the cycling of your slide (i.e. more recoil). I guess, however, in theory, the faster speed at which the slide kicks back might slightly speed up the valve knocker timing... but it shouldn't make a difference unless your piston head is cracked - apparently, this is common on TM 1911's and Hi-Capa's that are run on propane. However, if this were the case, your GBB would have a gas consumption of one shot per fill - the BB would shoot out, then all the gas in the mag would discharge after it.

Possibly. Pounce, if you vent your left-over gas from your mags after shooting, this will most likely freeze and crack your seals - making leaking mags. However, I have to disagree with Amos on the seals that you should be looking at - potential failure points (i.e. where leaks could spring up) would be the O-ring around the base plate, the fill valve, and the output valve. Well, that is, unless your seal at the top of the magazine is obviously cracked - but "duh"?

Ideally, if I were you, I'd find a friend/fellow local airsofter who also has working TOKYO MARUI single stack mags (MEU or 1911) and try those out. If that doesn't fix the problem, you likely have internal problems.

Internal problems (if you don't know what I'm talking about here, once you get to this step - bring it to a GBB gun doc who has experience with TM Hi-Capa's, 1911's, and MEU's) may include, but are not limited to - cracked loading nozzle, worn down/broken floating valve/valve blocker/floating valve spring (I doubt this one though... TM floating valves/blockers seem to be pretty tough in my experience), cracked piston head (pretty likely, TM piston heads are known to break under the stress of propane - but like I said earlier, I don't think this is the case). Or alternatively - sticky/stuck/dirty/broken valve knocker or spring (the part that holds the valve knocker in place against the chassis, or inner frame or whatever you call it), or something fucked up going on with your hammer/sear - but I don't have enough experience with TM parts for this one, and from what ILLusion has told me, the TM parts shouldn't fail unless the sear/hammer is mixed-and-matched with other parts that are made from different materials.

Oh - speaking of ILLusion - that's your best bet. Post this up in ILLusion's Hi-Capa/1911 FAQ somewhere on ASC. Chances are that you'll be able to get a good, solid answer there.

Thanks very much. Very informative to hear from two different perspectives on the slide internals. As for the seals on the mags, they are kept in good shape. I never vent my gas and always leave a little bit in the mag when they are in storage. I fire a few rounds from them regularly to keep them in good working order and I drop some silicon oil in them after 10 or so fill ups. I'm try switching out the recoil spring to the stock one first and tell you all how it improves. I switched out the slide on my 1911 for the slide on my detonics (looks awesome by the way) and fired a few rounds and I was getting amazing consumption. I could empty a magazine in a few seconds with very little cool down and still had enough gas after 20 rounds to lock back the slide. So I don't know if the hammer spring is making that much of a difference that I want to switch it just yet.

Sounds good! I'm glad to head that.

And LOL, a 1911 slide on a Detonics frame? Want to post up a pic of that, just for kicks?

hahah yeah. Other way around was what I meant and it looks sweet (detonics slide on a 1911 frame) but 1911 slide on a detonics frame is actually kinda cool. If you couldn't see the recoil spring it would almost look like a compact hardballer. Pics will come soon.

Ohhhhhhhh, I get it.

But still, my brain is going "whaaaaaaaaaaaat" and just not even being able to comprehend what that would look like.

Also check your nozzle to make sure it's not cracked. It is very common for them to rupture after upgrading to a metal slide and enhanced recoil spring.

It's also possible that your piston head's o-ring has ruptured or slipped off.

What brand slide are you using?

What barrel are you using?
Almost all aftermarket metal slide manufacturers do NOT intend their slides to be used with the original plastic outer barrel. Doing so will quickly destroy the plastic chamber, and may even cause cycling issues.

Also, how smooth is your slide movement? Restricted slide movement is the second main cause of excess gas consumption (next to poor sealing.)

You can see the nozzle damage only by disassembling the upper assembly.

I'll check my nozzle when I get home tonight, I didn't see any cracks in it though. I have yet to take down my blow back unit but I will today.

I'm using a guarder FMK with a guarder outer barrel. Yeah actually the stock barrel was the first thing I removed so my outer barrel hasn't been stock for a while.

The slide isn't restricted in any way I can tell. When I fire it it seems very smooth and when I slowly let it forward it doesn't catch on anything. I'm thinking its poor sealing because I fired it yesterday with the stock spring and it got a few more rounds but still not as much as I would like (13 instead of 7).

Well, if it is any consolation, I only get 16 rounds out of my FM MEU clone with TM mags when fire rapidly?

hmm interesting but I still think I can leech out some more power from these things.

You should definitely be able to. All the full metal single stack 1911's and MEUs that I build with enhanced recoil springs, I'm able to get 26+ rounds from it with successive firing to empty the mag.

Both of my FM 1911s gets around ~16-20 shots off a mag. But I run stronger hammer spring in them....