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Discussion Starter · #1 ·
Well working on my first 1919 build. I already have 2 1919's. I see some differences between this kit and my other 2 1919's and would like some expert opinions.

First the left side plate cam rivets have been ground flush. Is that going to be a problem down the road with the cams coming loose?



Second is the trigger pack frame is different on this kit. It doesn't have the little pin that sticks out by the accelerator, and it has a support that goes from side to side by the accelerator (see picture). Both by other 1919's have the pin as well as my spare trigger frame. Is this a standard piece or something special?



TIA,
Steve
 

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The lock frame at the bottom in last pic is GI....it is just missing the trigger pin.
The one above is Izzy.

For simplicity you want to use Izzy as they have the screw for your semi trigger return spring .
GI's can be converted....Paintmanmatt did a few.

There were many variations of lockframes built...at least 3 that I recall..Then some of those were Izzy modified.

On your cam rivets....easier to fix now vs later after the finished gun is parked etc.
Rivets are cheap & avl. Sarco & others have the cam rivets.
 

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Discussion Starter · #3 ·
Thanks for the info. I haven't ordered rivets yet so I will get the cam rivets at the same time.

I like the design of the izzy frame better than the gi anyway so I will use it.

Steve
 

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The top lock frame is cast (I'd guess Saginaw), the bottom one is built up from plate. If the denial island on your RSP requires that the "fork" on the right side of the Lock frame be machined, you may want to use the bottom one. Some builders have reported difficulty machining the Armasteel of the cast Lock frames, and that when this is done they are more likely to brake than the Lock frames assembled from plate steel. Your experience may differ.

Some manufacturers ground the rivets flush, others left the domes. I can't remember which did what off the top of my head. Flush Cam rivets shouldn't be an issue. MSG
 

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Discussion Starter · #5 ·
The top lock frame is cast (I'd guess Saginaw), the bottom one is built up from plate. If the denial island on your RSP requires that the "fork" on the right side of the Lock frame be machined, you may want to use the bottom one. Some builders have reported difficulty machining the Armasteel of the cast Lock frames, and that when this is done they are more likely to brake than the Lock frames assembled from plate steel. Your experience may differ.
Thanks for the info. I guess that means I have to use the fabricated one and weld the pin in after machining. While I have it in the mill I will also machine it for the return spring.

Steve
 

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Discussion Starter · #6 ·
Anybody have the part number for the sear slot "t slot" cutter? I am going to use a KMP trigger and sear.

Steve
 

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Steve, MSG is correct about the lock frames. The Israelis did not make any, as there was no need. But they did modify them for the screw, which makes timing a full auto gun much simpler. In WWII production, the cast lock frame was one more adaptation which Saginaw Steering Gear, and their sister Saginaw Malleable Iron Div, introduced to their production line once approved by the Ordnance Dept. All other mfgs continued to make the riveted plate style lock frames. On the plate versions, a simple flat was milled by the Israelis on the existing support pin, then the hole drilled and tapped for the timing screw. On the cast frames, a tall, vertical support was was milled out and a pin added by the Israelis to provide for their screw.

As to the accelerator stop pin, this was not required on the cast frames, as they milled the stop interface directly into the frame.

On your side plate cam question, the flush ground rivets were standard on all WWI production. As many thousands of WWI guns were upgraded to current spec prior to and during WWII, many retained the flush rivets unless a cam or cams were replaced. My bet is that your side plate, with the flush cams, will prove to be of WWI origin. Look to see if there is a slot inside about .100" above the lower edge. I see your bottom plate is detached, so the slot would be inside where is is largely covered when the bottom plate is installed.

To add to what theduke posted, there are several lock frame variations. Post war production, during and after the Korean war, produced two slightly different variations on the cast lock frame, quite distinct from the WWII Saginaw version.
 

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Discussion Starter · #8 ·
Checked my side plate..not an early plate. Someone did counter sink the side plate so the rivets should hold with the heads ground off, but I may replace them anyway.

Steve
 
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