"the gun trade is very secretive...."
Read my previous post again.
There was a very early 20th century, pre first world war, trade magazine called Arms and Explosives? I read an article in an edition which detailed in several pages experiments carried out by BSA using the Lincoln Jeffries patent underlever rifles they were making at the time. They experimented with light and heavy pistons eventually settling on the heavy for best overall performance in their production air rifles
That doesn't sound very secretive to me
As well as I can remember JB gave details in Airgun World of what he did in his air rifle conversions including information about piston heads, weights transfer port sizes, barrel locks, adjustable hinge bolts etc. Is there anything specific you want me to ask him tomorrow? Why don't you ring him and seek his advice yourself? It would save me the cost of a phone call
you seem quite hostile with me, I think it best we do not comment on each others posts going forward, we do not want to upset the admin now.
I respect your opinion, please respect I have my own too, if I offer advice its up to the in decidual if they choose to except it or not.
Everyone is entitled to their opinions and the right to state them providing it does not cause offence. I respect that. When a puzzling comment is made it deserves a response. Hopefully that response expands on the matter. That is called a discussion. That's how we find things out.
just do your own testing and make your own decissions....thats the best way...and what i do.
until you test it yourself how can you be 100% sure....i dont take anthing for granted until i have tested i it.
It would be nice to see you do some testing on a springer, with stroke, transfer port and piston weight all covered freely publushed on the forum :-)
The big thing I found out with that exercise was that you could increase the power output of certain guns by reducing the transfer port diameter.
The other classic example of this is the Webley Hawk MK2 --- sleeve the transfer port down and watch the power go up and the recoil come down.
U.K.Neil, kindly gave me a Webley MK3 at the Boinger Bash --- this is next on the list for a reduced transfer port.
All the best Mick
Exactly. In the 80s I remember the legions of tuners boring the TPs out and sticking in massive springs and polishing the bejesus out of everything to little practical effect ... even Webley up-gunning the Hawk to give the Vulcan with a stronger spring, 'advanced' piston washer 'system' and bogger swept volume ... when all they needed to do was sleeve the TP down. The difference between you and them is you did your thinking with your brain, Mr Mick!
What you've stated up above is something that's always been at the back of my mind.
Lack of bottle is one of the big reasons. My guns are all special to me and I'd hate to think I'd ruined it by going too far......Obtaining some near-to-worthless wrecks would certainly help in this regard!
I'm also hampered by a chronic lack of time and don't have the workshop facilities. If I had the time, bottle and gear, and could obtain enough basketcases, I'd LOVE to be able to delve a little deeper than my usual de-burr, polish, replace seals and fit guides etc.
So, to date, I've been happy with just making what's there just a little nicer.
Yes, I'd love to be able to play with sleeving down the bore and altering stroke etc. And, yes, I realise that, with the right gear, if you go to far with the TP diameter, this can be rectified.
But, sticking to the standard dimensions will do me for now, but I'll always feel very grateful and indebted to peeps like you, Mick. And Bigtoe and Wonky. There are more out there, too. Intrepid tuners who are happy to share their knowledge with us.
The Inaugural Spring Rifle Gathering at T20's. June 15, 2013.
2014 Boinger Bash, June 7 and 8. Open Airgun Gathering, September 6/7, 2014. Boinger Bonfire Bash Nov 8/9, 2014. 2015 Bash June 6/7.