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Posted By: forester Martini firing pin - need to bush? - 08/11/21 02:41 AM
I am working on a small center fire Martini action that I want to barrel/chamber for the 218 Bee. I was just reading through an old NRA publication "The NRA Gunsmithing Guide - Updated" that has an article written by Frank De Haas titled "Converting the 310 Martini". In the article De Haas says the main work needed on the action is to bush the firing pin to then allow for a smaller diameter firing pin. He says if the original is not suitably bushed the usual result when firing the 22 Hornet, 218 Bee or 357 Magnum is that the primer flows back in to the firing pin hole and binds up the breechblock.

De Haas recommends drilling out the firing pin hole and installing a 6 x 48 threaded bushing. Then drilling the bushing out to either 1/16" or 5/64". Then turn down the firing pin to fit.

In other articles and discussions I've seen over the years I don't recall anyone else bringing up the need to bush the firing pin.

I would appreciate if anyone can anyone offer experience with either bushing the small Martini or not bushing it?

Gary Erickson
Posted By: Der Ami Re: Martini firing pin - need to bush? - 08/11/21 12:24 PM
forester,
All of them don't have to be bushed, but most of them do. Some put the bushing from the front, others drill and tap from the rear with a"bushed" drill and tap( but turn the firing pin bushing in from the front). Both methods have advantages.
Mike
Posted By: Remington40x Re: Martini firing pin - need to bush? - 08/11/21 03:29 PM
I’ve owned more than half a dozen of these in various chamberings, including .20 Mashburn Bee, .22 Hornet, .218 Bee, .218 Mashburn Bee, .219 Zipper, .256 Winchester and .357 Magnum. The three of those which weren’t bushed when I bought them all needed bushing and got a trip to the gunsmith for same. Perhaps some original Cadet actions don’t require bushing the firing pin, but I’ve never owned one other than an original .310 Cadet which did not.
Posted By: Chuckster Re: Martini firing pin - need to bush? - 08/12/21 01:48 AM
My .22 Hornet Cadet required bushing. Used the cross dovetail method and seems to work well.
Chuck
Posted By: forester Re: Martini firing pin - need to bush? - 09/09/21 08:42 PM
I asked this question about the need to bush the Martini firing pin after reading about others that have done it. It was also in anticipation of taking the action to the Single Shot rifle gunsmithing class held at Grinnell, Iowa. I wanted to be ready to do the work in class if needed. But based on what I learned from Glenn Fewless in class and carefully measuring the action firing pin hole and the firing pin I am not going to bush the firing pin hole. I am going to shorten the firing pin protrusion though.

There was only about .002" - .003" difference between the diameter of the firing pin and the firing pin hole. But the firing pin had over .090" protrusion. Based on Glenn's knowledge and experience the tolerance in diameter was pretty good but the firing pin was way too long. I am in the process of shortening the firing pin down to about .040" - ,045" of protrusion and going to radius the tip of the pin. Might be next spring before I have the rifle complete and fire it to know if this worked or not. But I anticipate that this will be a good solution.
Posted By: bushveld Re: Martini firing pin - need to bush? - 09/10/21 01:35 AM
Gary;

What is the diameter of the firing pin hole and the firing pin fitting through the hole ?

Kindest Regards;
Stephen Howell
Posted By: forester Re: Martini firing pin - need to bush? - 09/11/21 01:46 AM
The firing pin is .090+" in diameter and the firing pin hole is .093" using both a pin gauge and an accurate inside mic.
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