View Full Version : Experiences with gearbox internals...

03-15-2005, 11:39 AM
Hello, I thought it would be a good thing for people to be able to post their experiences with different types (manufacturers) of aftermarket gearbox internals. So we could get an idea of good, better, and best parts. (maybe)

I have personally had very good initial experience with guarder products... I have a cylinder head, air nozzle, alum. piston head, and metal bushings all made by guarder. I was impressed with the quality as compared to the stock parts. I should be able to qualify that statement in a few months (and 10,000 rnds later).

Anyone else... do you have any internals with 10,000 rnds plus you could comment on? Pistons, gears, springs, bushings, ect...

03-15-2005, 12:02 PM
do you have any internals with 10,000 rnds plus you could comment on? Pistons, gears, springs, bushings, ect... A whole bunch. I keep a running spreadsheet of each of the parts in my replicas to get an idea of how many rounds they've lasted (or are lasting).
Trying to categorize them all here would be quite extensive.

Prometheus gears are hands-down the best I've seen. There is a post I made about them in this very forum. Systema are better, but do not compete with Prometheus gears. TM stock gears are good, as they'll last fairly long even with a M120 spring. No comment on current CA gears, but the old ones were a joke.

Prometheus hard pistons are best I've seen. Area1000 pistons are actually quite good and last plenty long given their low price. I prefer those to Systema pistons. Guarder pistons are good. TM stock pistons are fine for lower-powered stuff. G&P pistons I have little experience with because it got stripped very quickly, but that could have been a different issue, so no comment. Current CA pistons I have no comment on, but their old ones sucked. Have an Angel piston, but haven't tried it yet. Personally, I'm not a big fan of aluminum pistons....the ICS one that I had was made with a flaw......had a Systema one but it got destroyed, but that was due to a different problem, not the piston itself.

Spring guides with bearings aren't all that special. Systema, Prometheus, eh whatever. Pretty much the same with cylinders.

Guarder cylinder heads are good, as are their air nozzles. Systema cylinder heads are good, same with their nozzles. Haven't yet used the KM or Prometheus cylinder heads that I have.

Systema aluminum piston heads have treated me well. Never had a problem with one. I have Prometheus, Systema, and Angel polycarb pistonheads, but haven't used them yet. They all appear to be good quality. Also have a G&P polycarb piston head, which seems very, very cheap quality.

Guarder hopup buckings are great. I've had much better experience with them compared to Systema buckings. TM stock buckings have been good, if not better, to me compared to Systema ones. CA ones that I've seen in the past and currently are only good for filling the trash can.

TM tappet plates are the best in my experience. They have held up better than Guarder or Systema versions.

Springs? PDI springs are much easier to work with because they are shorter. Prometheus springs seem to have stable muzzle energy output from the start. Systema springs start high and then die off after a few hi-caps until they stabilize and then eventually weaken after many, many rounds. Seems like Systema springs vary more than others. Guarder springs seem pretty stable as well. I've seen Guarder springs actually fail by fracturing before the energy output decreased (that was about 37k rounds).

Overall, I'd say Prometheus parts are the best I've seen. After that, I prefer a mix of Systema and Guarder stuff. Many people overlook how well TM stock parts will hold up with M120 and lower springs.

I'd have to look at my spreadsheet to see the number of rounds I have on specific parts.

03-15-2005, 06:33 PM
Ive fired about 12000 rounds through my tm m733 which is completely stock except for an m120 spring and metal gearbox bushings. Not a hick-up yet. The gears have worked great under the stress of the m120, an eg1000 motor, and a 9.6v battery. All of the parts still seam to be in great condition.