Will a one piece firing pin fix light strikes problem?

[ba_50]

I have a JM 30/30. Anyone still have light strikes after installing a one-piece pin?
Thanks

[Pisgah]

What vintage is your 336? I can't recall what date the change occurred, but they used to be made with two positions, or slots, that the hammer spring retainer (actually called the "hammer spring adjustment plate" in some schematics) could be put in to. Sometimes, folks would move the retainer from the "strong" position to the "weaK" position to lessen the force needed to operate the lever. Nice option to have if you want easier levering -- but also resulting in a weaker hammer strike. I have "fixed" several light-striking rifles through the years by putting that retainer back in to the "strong" position.

As for a one-piece firing pin, it's a solution to a non-existent problem, and actually eliminates a very important safety feature provided by the two-piece pin.

[AJMD429]

What Pisgah said....

[JimT]

Strengthen the hammer spring.

The lighter the hammer spring, the more it negatively affects velocity and standard deviation.
Terry Murbach showed years ago how lightening the hammer spring changed everything. He took a S&W with the flat hammer spring and using the same loads, proceeded to lighten the spring by reducing the tension, step by step, chronographing each step. At some point he started getting misfires.

I have used the one piece firing pin in my 1894 32-20 for Cowboy Action. As has been said, it removes one of the safety features on the Marlin leverguns. I would never use it on a levergun that was used for hunting, home defense etc. I only used it on Game Guns.

[Fisher-Price]

Nope, been there tried it no difference on a 38-55 cowboy. Seems like I finally replaced a spring and reinstalled original 2 piece pin to get it back to firing.

[ba_50]

Did you try the one piece pin after you put a different spring in?

[fordwannabe]

I am not trying to be a smart aleck but did you thoroughly clean the firing pin channel. I have quite a few Marlins and the only issues I have had with light firing pin strikes was either the adjuster mentioned above, someone cut coils off the spring to lighten the trigger, or the firing pin channel was full of crud. Again not meaning to impose my opinions on your situation but those are my experiences.

[ba_50]

Soaked the stripped bolt for days and used a brush and pipe cleaner. Can't be that.
New main spring and two washers.
New rear pin
Everything smoothed up
Changed lever
Took hammer spur off
Mostly concerned with poor headspace even though the pin can be pushed to outer bolt rim.
Sized brass on shoulder
Tried different primers
Tried different brass rim sizes
Took it too a mediocre Smith 3x, no joy

[ba_50]

I took a new case, measured all around the rim and used the lowest setting. .062 primer extrusion on used primer.. According to that headspace should be ok

[Griff]

Simple answer: No, and firing pin protrusion is not a good indicator of headspace. Place dummy cartridge in chamber, use plastigage on rear of case, close bolt, measure how much the plastigage is flattened. Quick, simple, inexpensive and a reliable indicator of headspace. Not perfect... but accuracy has always been acceptable to me.

Are there no burrs in firing pin channel? and "bore" can develop or have a burr...

[CowboyTutt]

Strengthen the hammer spring.

The lighter the hammer spring, the more it negatively affects velocity and standard deviation.
Terry Murbach showed years ago how lightening the hammer spring changed everything. He took a S&W with the flat hammer spring and using the same loads, proceeded to lighten the spring by reducing the tension, step by step, chronographing each step. At some point he started getting misfires.

Jim-T

Mic McPherson has noted the same phenomenon with light strikes.

Simple answer: No, and firing pin protrusion is not a good indicator of headspace. Place dummy cartridge in chamber, use plastigage on rear of case, close bolt, measure how much the plastigage is flattened. Quick, simple, inexpensive and a reliable indicator of headspace. Not perfect... but accuracy has always been acceptable to me.

-Griff

You can also use multiple layers of scotch tape. Keep adding layers of tape until cartridge head makes contact and/or compresses tape, then peel it off and measure it. Repeat one time to verify. Reasonably accurate. -Tutt

[ba_50]

Scotch tape was added till the bolt would barely close on a new case. A bullet was pulled with an inertia puller so the rim thickness varies from .059 and .062.
The tape thickness was .010, which makes it borderline max on headspace.

[ba_50]

That still doesn't explain why headspacing on the shoulder didn't stop it.