does anyone have pictures of a rebushed firing pin.
Isa this a cross between a Nardini lathe and a Martini rifle?
When properly done, there is nothing to see, it looks just like a normal bolt face. The hole is just slightly smaller and round like new.
Not a martini but a highwall rimfire converted to centerfire....may give you some ideas
Originally Posted by ndh78
That's about the size of it, and once its final polished to #600 no one will know its been messed with. Nuff said !
[QUOTE=ndh78;1849657]Not a martini but a highwall rimfire converted to centerfire....may give you some ideas
Nicely done, but that is a welded breechblock, not a bushed one. It is OK for a low pressure round, but when going to a higher pressure round, the Mann-Neidner firing pin modification is recommended. This involves boring and drilling the face of the breechblock to install a flanged firing pin. The firing pin is retained with a bushing in the face of the breechblock. The purpose of this modification is to prevent gasses and potentially the firing pin being ejected into the shooter's face in the event of a ruptured case or pierced primer.
When a rimfire high or low wall breech block has been modified to center fire, the top of the breechblock must be drilled for the vent hole found on centerfire breechblocks.
Rather than welding the firng pin, it is simpler to face it square, drill and loc-tite or soft solder in a piece of drill rod or music wire of the proper diameter. This way, when the pin breaks, repair is much simpler.
I found this downloadable copy of the De Haas gunsmithing book on line. Since it is out of print, I will pass it on. It will answer any questions you might have about setting up your Cadet action. Good luck.
Chapter 1 for Mr Single Shots
I am fully aware of how the Mann-Neidner conversion is done and I don't think it is necessary, the welded firing pin tip is simply an experiment to see how it works I welded it with 4140 filler and will harden and temper it. I am also aware the block needs a vent hole and it will get one. Most problems occur because people try to use original blocks with worn holes and pins, a tight fitting small diameter pin should not have any problems.
I have a real copy of the De Hass book and I have even read it several times.
Actually ndh78 if you pack the sides in toilet paper soaked with salt water and work fast with the TIG there is no reason to re-heat treat it. You can have it Rockwell tested if you want, but all that will happen is that you will create a hard or soft spot about 1/32 of an inch deep and slightly larger than the size of the puddle in diameter. Often the weld area is within a point of the rest of the bolt. I have been down that road many times. Done quickly the TIG is extremely localized heat. I have a friend with a Rockwell tester at work and we abused the hell out of it learning this. Things have changed a bit in the last 30 years since guys like De Hass were burning the snot out of parts with acetylene torches and buzz boxs.
If anyone is looking for any of the Frank de Haas books his family is still selling them.
de Haas Guns :: dehaas.com
I was looking for a copy of one of his books on single shot actions a few years ago and was amazed at how much people were gouging for a copy on Amazon & Ebay. Then I found the families website, called them. The prices were really reasonable, I think ~$20 a book.
Like I said, it was few years ago but the website looks unchanged. I don't remember who I talked to when I called the number on the website, but it was I am pretty sure I was talking to a family member. An enjoyable, small shop kind of feel.
Last edited by mg81; 07-29-2012 at 04:07 PM.
If the books are still available from Mark De Haas, that is good news. I had heard a while back that not all were still available including the Gunsmithing Ideas book and the Single Shot Rifles and Actions book. I do have them all, including Single Shot Actions, Their Design and Construction, not shown on their site.
Frank Dehaas was a well known author and amateur gunsmith. In addition to the several books he authored, he was a long time contributing editor to The America Rifleman, and contributed to the major gun magazines of the day, including Guns & Ammo, Gun Digest, Shooting Times, Guns and more. Several of his how to articles were reprinted in the American Rifleman Gunsmithing book as well. In none of his articles did he ever "burn the snot" out of parts with buzz boxes and acetylene torches or encourage anyone else to do the same. Such comments accomplish nothing except displaying the ignorance of the writer.