I'm new to this forum, I put this on the Yellow forum a month ago and thought I would share it here as well. I really love my big bore guns. I bought my first Quackenbush 20 or so years ago. (SER# 175) I also have a Gargoyle, and a .357 Corsair. Most recently, I recently bought one of the .58 caliber Pistols that Dennis just built. I love shooting that gun,
Very accurate, 2 shots about 530 FPS shooting a 340 grain hand cast, sized semi wad cutter.
But as with most every air pistol,
It can't be holstered.
It pretty much requires both hands to carry it.
The knobs catch on everything, and the gun did get fired with the bolt open. (Not good)
No open sights. Why won't anybody put open sights on a pistol???
So I say "Quit whining and build one yourself, if you think you can."
I spent my whole career as a prototype machinist running manual lathes and mills.
My personal shop has a 13X40 Jet Lathe, and a nice vertical mill. And I am fully tooled up.
I have been busy in my basement shop. I have had a bunch of ideas to make a pistol like this for a long, long time. So 100 hours later, I have a totally Stainless steel gun. I used 17-4, 303, 304 and 316 alloys. I found out the hard way, you cannot use the same alloy material on mating parts for galling/ cold weld reasons. In my build, I used a .312 transfer port, the pressure chamber’s o-rings are inboard ( the threads don’t see pressure). There are no bolt or hammer handles hanging out. The bolt and hammer knobs all both behind the gun. I use a Vlier spring plunger to hold the bolt closed. I also use a large cross section O-ring that just fits between the bolt and the housing to add a little friction. It works super. The bolt is not coming open accidently. Another large O-ring is between the hammer handle and the housing so the hammer will never crash metal to metal. The hammer spring is
1/2 I.D.X.072X3.00 long. The spring guide is part of the hammer to add weight. The stainless barrel is .566. bore, .570 lands. I had these barrels made years ago from T.J. Enterprise. I want to use the .570 round ball that is swaged and commercially available. There are all kinds of internal improvements especially on the valve. I would have to show you the drawings. Which I can do. I don’t hold secrets. If this forum supports drawing files (DWG) I’ll publish the whole print for anyone that want’s to look/criticize my drawings.
I'm 60 years old and retired. I have a bunch of air gun related ideas that I'd like to share, I'd love to see someone else take these ideas and run with them.
I finished the gun about 2 months ago so I probably have close to 1000 rounds through it,.
Right now the Shoebox compressor is working overtime. This gun barks loud, and kicks like a mule. Look backwards before you shoot.
Because of the short barrel and air tube I get one shot at 570 FPS with a 3500 psi fill.
So I present to you: "BIG JOHN'S SON"
Full Stainless Steel.
Iron Sights. (and dovetail grooves)
Easily carries in a holster.
No clumsy Knobs.
About a 4 pound trigger. That might be the best I can do using the Crosman grip and trigger assembly.
Sorry, no shrouded barrel.
no silencer.
no carbine stock.
No scope.
This is a gun that I could drop in the woods and find 100 years from now, pick it up and fire it.
And YES, I am always open to any constructive critique.
Please, Let me know what you think. John
