I ported the valve stem on mine (opened the twin holes up quite a bit) and fitted a fully rifled inner barrel into all of my 29s & 629s (I've got them all) and it has definitely helped to increase the overall FPS performance and obviously the new inner barrels have increased the accuracy too. The washer that you've removed from the valve assembly is a 'crush' washer, made from a softer material (probably aluminium) that's designed to deform under pressure to allow a far better (notably stronger) seal between the valve seat and the rest of the valve assembly, these are disposable parts that you normally get in the Umarex valve service kit for the gun. The valve stem spring can be lightened to allow longer valve opening times but you've got to remember that the pellet will take a certain length of time to move from the cartridge, along the barrel and out of the gun, any gas being released after this time is just being vented rather than being used as a projection force. Porting the valve stem (or adding extra holes) is a more practical way to get the CO2 through the valve in the quickest possible way and increasing the valve opening time (by reducing the spring pressure in the valve stem return spring) is just wasteful when it comes to the propellant. If I was you I would concentrate on getting the inner barrel replaced before doing anymore 'adjustments' to the valve assembly as there is quite a bit of extra FPS to be gained from the gun by fitting a full length inner rifled barrel to it.
Thanks Rune. It’s certainly double the power now. I have a set of wood grips on order but will take a few weeks to arrive. Then I need to find, adapt and fit a rifled barrel. Then my quest will be complete in making the model that Umarex should have made in the first place. Well, in my opinion 🤣. I liked your Charlie vid btw. I look forward to seeing more on that one!!
@@Waxmax Thanks my friend. The Charlie is a cool beast of a pistol. Hope to make more videos of it soon. A rifled barrel in the M29 sounds great. After watching your videos I have been thinking of buying one, but they are quite expencive here. Its ca £220
@@runerebel8441 thank you. The price is pretty much the same here. Only £20 less. Money is money but the cost of these things is low considering most hobbies. What I really like about the m29 is that it has a great look, feel and action. The fact that as standard it shoots straight and has both elevation and windage. It’s just missing that rifled barrel, power and grips. I can’t wait to get it finished. You should get one!! I’ve always loved this model. Didn’t you have the airsoft version? If you did/still do, I bet it’s the same workings.
