timmy trees review of the Tinbum kit

[gary martin]

on the old forum. TT wrote a detailed review of the Tinbum kits for the pro sport. is there any way of retrieving the topic?
cant remember if it included a review of the short stroke piston extension or not.

[eboswan]

on the old forum. TT wrote a detailed review of the Tinbum kits for the pro sport. is there any way of retrieving the topic?
cant remember if it included a review of the short stroke piston extension or not.

sorry mate there is no way too retrieve the review but I`m sure if you pm timmy he will help you out.

[Timmytree]

Will this do? Luckily I'd posted it on the Canadian Airgun forum as well!

Right then, I was asked if I would review one of Tinbums kits and give my honest opinion. Nick got one in the post to me straight away. Before it arrived I put my PS back to all standard internals (including the huge tophat) to make a fair comparison. It was ok but after running with my own mods it didn't feel as nice.
The kit arrived, neat package with simple instructions, a new guide, 2 power bands, 1 slipwasher and a new tophat, all nicely finished. Nick asked me for any reccomendations that I felt would improve the kit but more of that later.
I decided to do the test with 2 different springs, my own partworn and a brand new one from Julian, I left the piston seal alone as it seems to be particularly efficient.
First test with the old spring.
Assembled as per instructions with 1 power band and fired a few shots into my ragbox, felt nice and smooth on cocking and firing, much the same as it felt with my own mods, over the chrono it showed a variation of about 8fps overall.
Changed the spring for the new one, nice smooth cocking but the firing cycle felt slightly harsher, changing from AA Fields to Falcon AP smoothed it out a little so maybe the heavier Fields were inducing a bit of piston bounce. I tried with and without power bands but the results were pretty much the same, upping the power beyond about 11.0ftlbs created a bit of harshness, not nasty but I was aware of it.
I then decided to experiment with different tophats, the 2 AA versions, the 1 in the kit and a V mach one that I had in the box. By the end of the week my Prosport had been stripped and rebuilt maybe 30 times for this review. Changing tophats allows you to balance the feel of the rifle to the pellets you would normally use, obviously the spring, piston seal and pellet fit will have an effect. I eventually settled on the TbT guide and slip washer, 1 power band and a highly polished steel tophat from a .22 PS, the worn spring and AA Fields.
The chrono figures were very good!
766,768,766.766,766,764,765,764,770,765,764,764,764,765,764,770,766,765,764,766.
Nothing much wrong there and the PS was feeling sweet, accuracy was up to par and to be honest it didn't feel much different to what I produced with my own tinkerings over the years, the difference was the time element and little faffing about.
Next I put in the new spring but removed the power band, tried with the TbT tophat, heavy AA and light AA, again the lighter AA felt best for me but I must stress that I think a newer or tighter seal would probably alter that.
The figures were again very good.
775,775.776.778,773,778,778,778,778,775,775,775,775,778,778,779.774,775,775,775.
After that lot I shot 3 x 5 shot groups at 35 yards, 2 of which were neat keyholes apart from one shot which strayed by maybe 8mm.

The intention was to then transfer the kit to Big Dogs PS for him to have a go but his PS is currently in bits awaiting attention after I opened it up and found a wear problem on the comp tube, that will be presented to AA for their attention as it's effectively a nearly new gun. Not happy! :maddy:
I have suggested that the tophat is machined down with a smaller block, this will allow owners to experiment by adding steel washers to increase the weight if needed or delrin ones to increase preload. Personally I would try a range of weights from all steel to all delrin to see which suits your rifle/pellet set up best.

Conclusions.

The TbT kit comes ready to fit to your standard spring, it fits and in most cases will instantly make your PS or TX feel smoother on the cocking stroke. For rifles with a tight seal I think a straight swap will be fine, some people with easy running internals may need to play around with weight around the piston but that isn't hard to do. The benefits of the TbT kit against others (not sure if I can name names?) is that by utilising standard springs you save a great wad of cash to start with, when it also comes to renewing springs in the future it will cost you around £17ish. 1 kit I had cost me £50 because I "have to buy the guide to match" or so I was told, needless to say that kit went in the bin, hence my reliance on mainly standard parts.
Is it worth the money? Yes, definitely. £20 well spent and from posts on other forums, lots of happy customers.
Nick is happy to give advice and customer satisfaction seems to be his priority, a nice change nowadays.
Final point, I had that kit for free and enjoyed testing it, I've now passed it to someone else (who will make a charity donation but he doesn't know it yet!)
I will though be buying another kit from Nick if he incorporates the change to the tophat to allow fine tuning.

[eboswan]

helpful as allways

[gary martin]

Timmy, thank you very much. did you ever test the short stroke kit?
Gary.

[Timmytree]

Timmy, thank you very much. did you ever test the short stroke kit?
Gary.

No, never felt the need to go short stroke. I was always concerned about increasing the power needed to cock the PS, the bolt through the cocking shoe into the comp tube is fairly small and may be the weakest link in the whole set up. If that fails it means a helicoil or new comp tube.
The PS can be made very sweet with just a few tweaks of the standard kit.

[tony1]

great info timmy, might get one to see how it compares to my vortek kit in my tx.