Banned
remember however, if the gun you have is nice already, why alter it?
If you must experiment drill the TP to 4.2mm and tap to m5, get some 6mm long m5 grubscrews and have them drilled from 3 to 4mm in .1mm steps, use a little blue loctite to hold them in and seal the threads, you can now play with TP dia and see what works for you
A little heat and an allen key gets them out, run the tap back in to clean the threads and screw a new one in to resume testing.
Registered User
"I tested 3 to 4.2mm in .1mm steps and settled on 3.9, i know Wonky likes 3.9 also, JB likes 5/32 which is just a nats over 3.9, T20 uses 4mm, BTDT runs 4mm on his 77k....the list is long for rifles that all run very close to the same transfer port dia...now ask yourself why"
The list of many longtime professional "tuners" who kept to the original or even sleeved transfer ports is even longer..... now ask yourself why? from first hand experience I include in that list Cardew, Mike Wade of Power without Powder fame, Venom, Worcestershire Black Powder Supplies, Kestock and many more. They must have done a half decent job to stay in business as long as they did with many repeat customers.
The best piece of advice is.
"If you must experiment drill the TP to 4.2mm and tap to m5, get some 6mm long m5 grubscrews and have them drilled from 3 to 4mm in .1mm steps, use a little blue loctite to hold them in and seal the threads, you can now play with TP dia and see what works for you
A little heat and an allen key gets them out, run the tap back in to clean the threads and screw a new one in to resume testing"
Administrator
I thought Mike Wade just supplied his "Viper" tuning kits and didn't actually tune guns for anybody ?Originally Posted by greenwayjames
If you look at Mike Wade's order form that came with Power Without Powder, he recommends drilling the transfer port out on the 77 for both his Max power and FT Viper tuning kits.
All the best Mick
Registered User
My mistake. I was thinking of his recommendations for the HW80 tune. He did tune some himself for a chosen few in addition to selling his 80 springs. He also made a regulated high power PCP for his own use I was lead to believe. Ahead of its time.
Administrator
He recommended drilling the HW80 transfer ports out as well.My mistake
All the best Mick
Administrator
And come to think of it Cardew wasn't a professional tuner either.
Though he did do a few experiments where he opened transfer ports up.
All the best Mick
Registered User
Did he really. I no longer have a copy so I will take your word for it. Cardew used to tune quite a few rifles for shooters in addition to repairing/restoring antique pneumatics, Giffards etc. He charged for the work he did. Cant agree with you about ports having read his books.He recommended drilling the HW80 transfer ports out as well.
All the best Mick
The main point of my first post was to agree with the advice that whatever you do should be "undo-able"if it doesn't work out
Administrator
Yes he did --- in both editions of Power Without Powder (there were two different editions) Mike recommended opening the HW80 transfer port out.
As good as Trigger to Muzzle is and how revolutionary it was when first released in 1976 you need to bare in mind that a lot has changed in 37 years.
In 1976 calculators were in their infancy --- 1977 being the first year they were deemed good enough to use them in O level exams.
Decent cheep chronographs were unheard of.
Digital scales were unheard of.
And all Weihrauchs had Leather seals fitted back then.
You would need to have followed Gerald Cardews later works in Airgun World to have read his transfer port and stroke experiments.
Most home tuners on here have equipment which Gerald Cardew could only have dreamed about in 1976.
Amen to thatThe main point of my first post was to agree with the advice that whatever you do should be "undo-able"if it doesn't work out
All the best Mick
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