I've always loved to take things apart, rebuild them etc. so Airsoft is an ideal - if new discipline for me.
I have a TM G3/SG1 (my first airsoft gun in fact - bought 2nd hand) which is was a good, reliable pew-pew, but after chrono'ing it the other week - a mere 205fps showed its age.
As I have other AEGs in the 300-350fps range and, given the style of the gun, DMR seemed the logical choice.
So I set about sourcing a Systema FTK-11 - but they are thin on the ground and pretty pricey. I also had concerns about using a stock gearbox casing with a monster spring and besides, my site limit is 425fps for DMR locked to semi, so a 150 would have ben overkill. Which led me to Guardena. An ITK-33 kit looked to do the job, though I ordered a 130spring in case the 120 with the kit wasn't quite up to the job.
So, with tools, youtube vids and teardown guides in hand, I set to it. I'm prett mechanically minded (have scratch built 5 cars) so how hard can it be?!
The key is patience. Tolerances in a gearbox are very tight and time spent shimming well is time well spent for performance and reliability. Starting with the motor to pinion and then onwards, a logical approach is required. I radiused the gearbox casing etc. and applied pretty much every tech tip out there - even emploting feeler guages for gear shimming.
I replaced the barrel with a 'Tomtac' stainless 6.02mm. Never heard of them - but as chrono showed, it was a wise choice (and only £23!).
Anyway, without boring you with a complete teardown and rebuild, it was with some trepidation that I first pulled the trigger...
But needn't have worried! Semi and then full auto were smooth as butter - happy days.
So then to the numbers. The chrono doesn't lie and I was expecting about 375-385 with the 120 spring.
The reality - 410-417 with a 10 shot average of 409 Over the moon with this!
Even with the stock TM bucking and hop it shoots like a laser and I wouldn't want to be on the receiving end of it! I've racked up plenty of kills with it at 205fps - now it's a monster!
So, the reason for the post? If you're
mechanically inclined, don't be scared to have a go. I'm not trying to discourage use of techs as they are professionals, but it's very rewarding doing the work yourself and getting the results you wanted. Perhaps I got lucky, but I spent a good 6 hours on the upgrade and hopefully that will paid dividends. We shall see
I have a TM G3/SG1 (my first airsoft gun in fact - bought 2nd hand) which is was a good, reliable pew-pew, but after chrono'ing it the other week - a mere 205fps showed its age.
As I have other AEGs in the 300-350fps range and, given the style of the gun, DMR seemed the logical choice.
So I set about sourcing a Systema FTK-11 - but they are thin on the ground and pretty pricey. I also had concerns about using a stock gearbox casing with a monster spring and besides, my site limit is 425fps for DMR locked to semi, so a 150 would have ben overkill. Which led me to Guardena. An ITK-33 kit looked to do the job, though I ordered a 130spring in case the 120 with the kit wasn't quite up to the job.
So, with tools, youtube vids and teardown guides in hand, I set to it. I'm prett mechanically minded (have scratch built 5 cars) so how hard can it be?!
The key is patience. Tolerances in a gearbox are very tight and time spent shimming well is time well spent for performance and reliability. Starting with the motor to pinion and then onwards, a logical approach is required. I radiused the gearbox casing etc. and applied pretty much every tech tip out there - even emploting feeler guages for gear shimming.
I replaced the barrel with a 'Tomtac' stainless 6.02mm. Never heard of them - but as chrono showed, it was a wise choice (and only £23!).
Anyway, without boring you with a complete teardown and rebuild, it was with some trepidation that I first pulled the trigger...
But needn't have worried! Semi and then full auto were smooth as butter - happy days.
So then to the numbers. The chrono doesn't lie and I was expecting about 375-385 with the 120 spring.
The reality - 410-417 with a 10 shot average of 409
Over the moon with this!Even with the stock TM bucking and hop it shoots like a laser and I wouldn't want to be on the receiving end of it! I've racked up plenty of kills with it at 205fps - now it's a monster!
So, the reason for the post? If you're
mechanically inclined, don't be scared to have a go. I'm not trying to discourage use of techs as they are professionals, but it's very rewarding doing the work yourself and getting the results you wanted. Perhaps I got lucky, but I spent a good 6 hours on the upgrade and hopefully that will paid dividends. We shall see
h34r: 
