High and low wall firing pin brakage

[gunlaker]

Glenn, when you had your CSA firing pin set back, do you know what the pin protrusion was when it was bad, versus when you got it fixed?

thanks,

Chris.

[SSShooter]

Hi Chris - if I wrote things down correctly, the bad firing pin was 0.8075" and the replacement is 0.8165". However, the side of the firing pin assembly where the hammer strikes is not normal the axis of the pin portion, making it difficult to measure the length in a consistent manner. My measuring tool is a digital caliper.

[Woody]

I measure the pins by what protrudes from the face of the block. When I repair a pin, I first make it too long and then measure the protrusion from the block face. I then trim it back until the protrusion measures .055 inch. That gives me consistent ignition. I have seen a lot of variance in the measured overall length of original pins, but they all protrude about the same.

Woody

[mdeland]

Yes, that is the correct way to measure them Woody and .055 is a good protrusion.
That's good to hear that the rimfire pins seldom break. I would have thought it would be just the other way around in that they would have been more likely to break the tip off than would the center fire.
High walls, if set up right and properly timed ,especially the coil spring models, seldom are out of action from part breakage from what I have observed.
I still think I'll go ahead and make one though for a spare to keep in my shooting box.
I have timed High Walls before and have a Dehaas jig, built just for that purpose. Mike D.

[gunlaker]

My CSA .45-70 definitely less than 0.055". If I remember correctly it's closer to 0.045" from the face of the breech block. I should compare with the others I've got. I have never had a misfire, but I've been meaning to order a spare pin for that one anyway.

Chris.

[deerhuntsheatmeup]

I am with Woody, if KO Roos said it about a Highwall, you can't just about count it being that way. My Roos built Meacham has had thathathousands of rounds and not a pin break yet, yet I said.

Anyway, my original Low wall in 22 rim fire has not broke a pin yet.......are you seeing a trend here? If they are built/fixed correctly, you more than likely won't have many problems.

Best, Barvid

[mdeland]

Protrusion is more for large rifle center fire than for rimfire. Center fire pins need to be around .074 in diameter plus or minus .002 with about .064 protrusion plus or minus .002. Small Rifle center fire pins should be .062 in diameter +/- .002
protrusion .050 . .22 rimfire should be about .050 diameter and protrusion about .037 +/- .002 according to Roy Dunlap who I have always found to give sound advice.
I was thinking of the Small Rifle centerfire figures Woody when I read your protrusion of .055 for .22 RF. Dunlope does go on to say that he is not a .22 RF specialist but these figures were good to the best of his knowledge and experience. Mike D.

[Woody]

Mike my protrusion of .055 is for centerfire not rim. In my own experience, protrusion much more than that will cause pierced primers, especially with large pistol primers, which are my preference for most of my BPC rifles.

Woody

[mdeland]

Oh,my mistake , I thought you were talking about rimfire and I didn't want to give the wrong dope so went and looked it up. Dunlop did say that Large and Small center fire rifle pins should have a" hemisphere point" profile to prevent primer penetration.

[mdeland]

I think you have a good idea Woody with your less protrusion while using pistol primers. Makes sense and of course Dunlop was not addressing this when he came up with his recommendations. Good discussion and exchange of information. I really like these round table type threads kicking around ideas and hearing different ways of doing things. Mike D.

[SSShooter]

As we are having a 'snow day' with 4" of the white stuff (I really do not like snow) and 10F out there with a nice breeze, think I'll pull the block on my High Wall and check the protrusion on all my firing pins.

There is a thread from about a year ago where I described the fact that I was getting inconsistent ignition with my High Wall. A number of folks thought that if a primer goes off at all it ignites completely. However, high power folks have learned that seating primers to the same depth and striking them the same each time is a must to be a top competitor. And my experience is the same with BP, where my shots at the rams/600yd would have feet of vertical rather than inches. Once that issue was repaired, the problem went away and it is now up to me.

[Clarence]

I have two Martini .22's. As purchased, they had in excess of 0.050" protrusion, which meant that accidental dry firing would peen the edge of the chamber. After seeking some advice, I ground them to a rounded chisel shape, with 0.035-0.037" protrusion. Consistent ignition with excellent accuracy, even after one of the mainsprings was lightened to achieve a 2 1/2 lb. trigger pull.

Clarence

[Woody]

SSShooter,

I totally agree with what you have posted concerning inconsistent ignition. I have broken a couple of pins in High Walls, my CPA Stevens, and the transfer bar in a Shiloh. Each time they continued to fire, but accuracy went to Sh#t.

Woody

[JDM]

I have a couple high walls with Mann Neidner pins. The conversions work good with smokeless powder but are a disaster with black. The pins rely on a very small coil spring to pull the pin back. With black powder the residual fouling gets in the pin holes after while and holds the pin foreward BINGO! a broken firing pin. If you are shooting a match it will always break in the middle of a string. I made that Mann Neidner conversion to fix a problem with a .219 improoved zipper gun. This old black powder gun with a stiff charge of smokeless would cock the hammer every shot. Instead of welding the block up and putting a smokeless pin in it I did the conversion.It worked great till I put a black powder barrel on it. After a hand full of broken pins I traded blocks with another action with an original smokeless firing pin. Problem solved. It seems like the O.D.G. had it figured out.
Dave Maurer

[Woody]

Dave,

I too have one High Wall with it's original Black Powder large diameter firing pin. It's my 40-65. I can't load pistol primers in it because it will pierce them every time. So I use CCI BR 2's in it. It's actually my most accurate rifle for silhouette, and it's never broken it's 100 plus year old pin. I'm building up another High Wall in 45-70, it too has a old large diameter firing pin. Hopefully I will have the same experience of carefree shooting with it. I do plan on taking one of my repaired small diameter pins and converting it to large, so I will have a spare. Just in case. I've got a few inches of .125 in diameter music wire that should work.

Woody