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Some Help With My A.o. 1927a-1 Firing Pin


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#1 steely

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Posted 15 July 2008 - 09:11 PM

Hi all,
I'm another Newbie here,
I was having some trouble with my bolt and searching for resources,
and I found you!
a whole website full of Tommy Gun experts!
I hope some one can help me in my plight!

New to my collection is a used Auto Ordinance 1927 A-1 deluxe,
I had to replace the firing pin pilot, and the firing pin retracting pin,
I thought I had done everything right, just as I found it,
but now that the gun is re-assembled, as I tip it from floor to sky,
I can hear the firing pin slide back and forth.
On a dry fire test, the gun seemed to fire, but I could hear the firing pin rattle as it did.

did I just assemble it wrong?
am I missing a part?
what keeps tension on the firing pin, when the gun is not cocked?
can anyone help?
or at least point me in the direction of a detailed break down of the bolt?
Thanks everyone!
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#2 Norm

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Posted 15 July 2008 - 09:30 PM

Welcome!

Here is a breakdown of the upper with bolt....

http://www.tommyguns...com/main_t1.asp

To the right, it asks "Do you want to see the images of all the parts?" Change this to "SHOW ME" and you will see the parts breakdown.

Make sure the small pins (parts labeled 16 and 17) are in the bolt!

I do think that you will hear some play if the firing pin released (after dry-firing), especially if the chamber is empty.

The firing pin will protrude much further than it needs to fire the round (about 1/2" in some cases.) This is one reason why heavy dry-firing the 27A1 can break the pin.

This is the rattle you hear.

Maybe others can help you more...

Norm unsure.gif

Edited by Norm, 15 July 2008 - 09:42 PM.

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#3 Motorcar

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Posted 15 July 2008 - 10:14 PM

The firing pin shouldn't be flopping around in there loose. There should be three springs holding the bolt forward, the two recoil springs that are smaller in diameter mounted on the guide, and one larger one in the center on the firing pin pilot. That center one runs inside the bolt and contacts the hammer which in turn holds pressure on the firing pin until released by the sear. The hammer is just a round cylindrical piece of steel a bit over an inch long. Even with the firing pin released and the bolt forward in battery the hammer and spring will hold tension on it. It will not sound loose or rattle around in there. Do you have the hammer installed?

One other thought is there were two styles of firing pin on '27A1s depending on year of manufacture. Is yours a West Hurley or newer Kahr production, that could be an issue.
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#4 steely

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Posted 15 July 2008 - 11:43 PM

Thanks Norm for the link,
that's a great thing to have.

to "Motorcar", thanks for your reply,
the hammer is installed, and if it supposed to maintain pressure on the firing pin,
it isn't, I must have installed something wrong.
since the hammer, spring, and pilot, all just slide in the end,
I am assuming I have seated my firing pin wrong.
any tips on how to do that?
could I have it in there somehow wrong?

by looking at the diagrams,
I don't seem to be missing any parts,
in fact, it seems that I have an extra part,
there is a small, brass sleeve on the firing pin pilot,
it rests against the ridge near the end of the pilot, and the
pilot spring rests against it.
that was how I found it on initial breakdown,
but I cant find the brass sleeve in any diagrams I have seen.

and last but not least,
being new to Tommy guns, I have no idea if it is a W.H. or Kahr,
it says auto ordinance, and I was under the impression that they
were bought out by Kahr.
According to the parts list from Norm's link,
I seem to have the "Short tip design" for a firing pin,
if that helps any.

Thanks to you both for your help
steely


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#5 Weasel

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Posted 16 July 2008 - 12:40 AM

Steely, I have an old WH tommy and I had some trouble with the WH bolt and the silly flat nosed FP. It never worked that good. I bought a Kahr complete bolt with the round FP at the nose and had to mill .010" off each side to get it to fit in the rec. I run sticks and a drum without a hicup with all types of ammo. I now enjoy the gun even more. I have shoot lead, rdnose, flatnose, HP, ball, and any free ammo that people have given me. I ran some reloads with two rounds that were double charged, big boom. Had to pull the case out with needlenose. No damage to gun. Stay safe.
Have fun with her.
Weasel
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#6 Motorcar

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Posted 16 July 2008 - 11:53 AM

Well, Okay....

I've not seen one with a brass sleeve but perhaps the fellows here with the older WH ones can speak to that. If your rifle has on the right side of the receiver "West Hurley, New York" under Auto Ordnance then it is a WH. Sounds like yours maybe an early production Kahr. It would be stamped "Worcester, Massachusetts" in the same location. If I remember correctly the early, or transitional Kahr rifles had the older WH design firing pin, or flat nosed. Then it was converted to the less prone to breaking desing of today. I think if it were me I would replace the center firing pin spring first in case the previous owner stuck a 1911 spring or who knows what in it to solve some other problem. That would be the cheapest thing to try before looking at other options and may be the obvious issue. Maybe the reason for the sleeve...wrong spring?

I doubt you installed the firing pin wrong as it seems to function.

PK would be the one to ask if you come up against a wall on this, he has seen and fixed them all!!
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#7 steely

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Posted 16 July 2008 - 09:36 PM

all right guys,
thanks again for all your help,

I may have the issue narrowed down,

First off, my gun is a West Hurley,

that said, I think my center firing pin spring is too short,

am I right in thinking that the spring should rest against the rib near the rear of the firing pin Pilot,
and reach all the way forward to the hammer, providing pressure against it, pinning it up against the firing pin?

it seams my spring is significantly shorter, and the brass sleeve was inserted to make up for the slack,
and now it seams the spring has collapsed some, and the sleeve doesn't take up all that slack.

When the upper receiver is fully assembled, and resting on my table upside down, I can reach in and slide
the center spring a quarter inch back and forth on the pilot pin, between the brass sleeve and the hammer.

does any of this make sense?

can anyone tell me how long that spring should be?

and the best place to find a replacement?

Thanks guys,
I think I am getting closer to having the old tommy back on the range!

p.s. living in Washington State, I sure envy all you "true" Tommy gun owners!
I have never had the wonderful feeling of full auto!
steely
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#8 Z3BigDaddy

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Posted 16 July 2008 - 10:02 PM

QUOTE (steely @ Jul 16 2008, 07:36 PM) <{POST_SNAPBACK}>
p.s. living in Washington State, I sure envy all you "true" Tommy gun owners!
I have never had the wonderful feeling of full auto!
steely


Don't know about the spring but it's just a bit south to class III freedom... Where bouts in WA?

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#9 Motorcar

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Posted 16 July 2008 - 11:29 PM

QUOTE
am I right in thinking that the spring should rest against the rib near the rear of the firing pin Pilot,
and reach all the way forward to the hammer, providing pressure against it, pinning it up against the firing pin?


1.YES

2.Auto Ordnance/Kahr parts dept.

Edited by Motorcar, 17 July 2008 - 11:48 AM.

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#10 Norm

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Posted 17 July 2008 - 01:49 AM

QUOTE
it seams my spring is significantly shorter, and the brass sleeve was inserted to make up for the slack,
and now it seams the spring has collapsed some, and the sleeve doesn't take up all that slack


Someone may have shortened the spring intentionally to reduce the amount of effort it takes to cock the gun.

The 27A1 has enormous spring tension!

Norm

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#11 Weasel

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Posted 17 July 2008 - 11:50 AM

Steely,
I think I have a new FP spring. E-mail me and we can take some measurements. If it is good then its yours, for the cost of mailing.

fifensky@hotmail.com

Weasel
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#12 steely

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Posted 18 July 2008 - 01:35 AM

Wow,
Thanks for the offer Weasel,
unfortunately, by the time I saw your post,
I had already ordered a new one from Kahr.

Thanks to all of you guys,
you have been a tremendous help,
I'll be sure to let you know how this spring works.

by the way, just how far south is it to the nearest class III?'
I'm in the Northeast corner of Washington,
60 acres of timber,
my little slice of heaven

thanks all
Steely
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#13 Z3BigDaddy

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Posted 18 July 2008 - 01:52 AM

Hmmm.... Coleville area? I've hung out in the big city of Ritzville.... Best to head to Ideeho....
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