Heavier Hammer

[PakProtector]

Douglas
are you using the .25 cal TJ liner ? with you bored out valve to make all this power ?
looking forward to seeing the results.
i have a .357 TJ liner sitting at Jim Gaska's to be machined
was going to make a .357 Mrod (my version of the Rogue) but have changed directions, already have too many big bores now
if any one is interested it is available, also have an LW .357 barrel

A 1/2" OD .25 Auto liner from TJ in 26" length, 53 gr boolits from either a 252435 Lyman or a 25-050-RN RCBS and a valve like mine will take you to ~100 FPE. Other stuff should include a 110 gram hammer and a 15# hammer spring. The TJ barrel has shown ability to still handle pellets, and it is possible to significantly reduce both hammer strike and fill pressure and shoot at half the boolit energy efficiently.
cheers,
Douglas

nah, not yet...still encumbered by the BSA pellet barrel. While it puts them downrange, it is not as well as I'd like. It will eventually get the TJ 25 Auto. The first one is the .224 Hornet liner. Going to build a boolit shooter in 22 cal first. After than it may be that I will stick with the 25 for close-in squirrel work( as in less than 80 yards ). One more valve experiment to try today... At some point I suppose I will go too far and have to start over. May be close in some things already.

Gotta get my new tank ordered; it won't be much longer...
cheers,
Douglas

[DR650]

valve poppet made with a PEEK head. tolerates a larger throat on a thinner sealing face. Made by me( well...for me ).
cheers,
Douglas

This interests me since I am making a Peek poppet valve right now. I experimented with a .100 oversize poppet valve. stock is .335 and mine are .435. My throat is opened up to .300 where the norm is .250
My spring pocket, don't know what it is called is opened up to .600 for a section of it around the valve and .500 between the breech mounting holes.
I tried peek, nylon and teflon. The teflon sealed really well but broke the firs shot. The nylon worked but had a slow leak and seem sticky, stuck to the seat after sitting
The peek just plan leaked, badly. Today I went back to peek, the leaking poppet valve and using fine valve grinding paste worked it into the valve just like lapping engine valves.
I took a 3/8th aluminum rod, drilled a hole in the end that the poppet valve would press into and then with the valve mounted in the lathe and grinding paste on the poppet. Holding the aluminum rod in my hands, the lathe spinning the valve I would push it in against the seat, on and off pressure grinding the seat. I now use the raise lip you see in the valve, stock poppets do not use this raised lip, they sit inside it, I use it for my seat allowing a .300 throat.
My .161 exhuast is polished with a strip of emery paper to radius the inside like an on ramp on the expressway. the .300 throat only goes to the back side of the exhuast creating a up sweep for turning the air.
I tested the peek poppet for leaks after the lapping and while all leak is not gone it is really minor so tomorrow it is back to the lathe and lap a bit more.
I am getting really good at taking these guns apart . A few months ago I didn't have a clue and now look at me
The large poppet without the .300 throat on 1100 psi regulated pressure was running at 840 fps.
I now have the larger throat, the more radiused exhaust and bumped the regulator to 1500 psi to try for more speed.
I would really like to here how your valve turned out

[DR650]

Can't find much on Peek valve. Someone who looks like they're making them has a web site that's seems down. Some where else I heard they are made from Ti. Any info on the valve?

I got a foot of 1/2 inch peek for $43 and use 1/8th by 1 1/2 inch dowel pins for stems. Doesn't take long to turn out custom valves if you have a lathe.
Peek is amazing stuff, strong like steel, can be used in steam and high temperature applications and machines really nicely, good finish but you can tell it is tough .

[DR650]

Can't find much on Peek valve. Someone who looks like they're making them has a web site that's seems down. Some where else I heard they are made from Ti. Any info on the valve?

its amazing stuff
http://www.victrex.com/en/products/vict ... AqY38P8HAQ

[rdsail]

I'm in the process on finishing up my build. The only thing that is left is get my barrel back from the machinist.

it will be a 26" TJ .25 14" twist barre. I will have a 10 in LDC and a CF UD liner. The lead is being machined for 55 and 65 g swags.

Right now I have a GEN .25 modified Valve with .203 exit port and .256 throat. It also had some flow improvements. The ID of the valve has being bored out to ½ all the way down to the sit and a PEEK poppet.

They will be used with my 109g hammer and 12.5 or 15 pound hammer. I casted lead in the side opening.
if this does not work out I might try a WAR valve.

My first goal was over 80fpe but now I'm shooting for 100+