Barrel twist rates
Select Gate
READ GTA FORUM RULES BEFORE POSTING
GTA Forum Help Desk
GTA Announcement Gate
Dealer Area
GRIP
AirgunWeb Airgun Videos
Airgun Repository of Knowledge
Vendors and Vendor Videos
AirGun Expo 2021
Airgun Expo 2022
Contests and Giveaways!!!
Welcome New Members
In Memoriam
GTA Contributing Members
Shot Show Videos
Hajimoto Productions
Airgun Detectives
Air Gun Gate
BB Guns and Such
"Bob and Lloyds Workshop"
American/U.S. Air Gun Gates
European/Asian Air Gun Gates
PCP/CO2/HPA Air Gun Gates "The Darkside"
Air Archery
Vintage Air Gun Gate
Air Guns And Related Accessories Review Gates
Hunting Gate
Machine Shop Talk & AG Parts Machining
3D printing and files
Buyer's, Seller's & Trader's Comments
Bargain Gate
Back Room
Target Shooting Discussion Gate
Target Match Rules
Shooting Match Gates
Field Target Gates
The Long Range Club
100 Yard Match
Discussions By States
Welcome,
Guest
. Please
login
or
register
.
Did you miss your
activation email
?
1 Hour
1 Day
1 Week
1 Month
Forever
Login with username, password and session length
Home
About
Help
Old GTA
Gallery
Search
Stats
Login
Register
Advertise Here
GTA
»
All Springer/NP/PCP Air Gun Discussion General
»
Machine Shop Talk & AG Parts Machining
(Moderators:
Rocker1
,
GTA-Airgunner
) »
Barrel twist rates
« previous
next »
Print
Pages:
1
[
2
]
Go Down
Share This!
Author
Topic: Barrel twist rates (Read 5412 times))
grandadg
Shooter
Posts: 33
yes
Real Name: Graham
Re: Barrel twist rates
«
Reply #20 on:
February 16, 2017, 06:16:13 PM »
Cheers Bob I see where I went wrong now. Too fine a radius and to long a shank. !! thought I was being clever by making the end just a shade longer then the depth needed and using fine diameter to be able to move the tool post back and forth without fear of catching anything,like I usually do when the tool is short
my square blanks are too big I'll have to order some smaller ones. I started grinding a cherry cutter to alter one of my molds today man that stuff is hard to grind so I had to go carefully I just need to true up the stem in the lathe before attempting to mill the half off,as I did the major grinding down to size on the bench grinder before changing to the Dremmel and cutting wheel. So as you can imagine their is a wee bit of truing to do.I am trying to find all my pics of some of my gun builds to show you guys, as I have tons of QB builds with all sorts of crafty mods and easy upgrades. And I know a lot of the guys are into the QB's in a big way same as me. I actually make replacement valves with PTFE heads for the lads on the UK Chinese airgun Forum.Not only are they lighter but last a lifetime too. I am using ptfe as the guns are only for sub 12fpe and delrin was proving that the faces of the brass valve boddies was not all they should be with some of them so out of true it was proving to be a nightmare for some of the guys.So I went to ptfe as it will pressure form to the shape of the exhaust valve opening face quite nicely without the need for the guys who lack any kind of DIY skill to get into a sweat when they fit them. I have used them on higher powered guns and found them tom be OK too but worry that they might be needing a bit more oomph to get them unstuck after a few sessions because of the higher spring pressures from the valve and the hammer during firing I imagine they are pressing into the airway cavity and being shaped to that rather than the flat surface on the edge of the airway.
Logged
South Shields, England
grandadg
Shooter
Posts: 33
yes
Real Name: Graham
Re: Barrel twist rates
«
Reply #21 on:
February 17, 2017, 07:49:49 AM »
Couple of valves I make first is the QB valve stems and second is the Crosman valve stem my one is on the left the original is on the right
With this piston extension and O ring seal replacing the standard seal enables even more preload to be removed from the mainspring for a very nice kick free 11.5fpe on the Air Arms TX 200 ,lovely smooth firing cycle giving superb accuracy.
Now my aas200 with 24" BSA barrel .177 and extended air tube running a lanes regulator
an extremely accurate gun
one shot flew low during the group (possibly damaged pellet) but these were the very fist shots following build. I think you can all see which pellets she loves.
Logged
South Shields, England
Print
Pages:
1
[
2
]
Go Up
« previous
next »
GTA
»
All Springer/NP/PCP Air Gun Discussion General
»
Machine Shop Talk & AG Parts Machining
(Moderators:
Rocker1
,
GTA-Airgunner
) »
Barrel twist rates