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Recoil Spring Issue


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#1 TommyFan

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Posted 22 November 2003 - 11:22 AM

As this is my first post to this forum, I'll be brief. I have a new Kahr Arms M1 Thompson having an issue with double feeds. I get almost as much of a workout cocking the bolt as I do doing chin-ups. Does anyone know of a kit with springs with less tension that is available? Thanks for any help you can give me. I found a lot of great information so far on this site when I can actually get through the archived postings (ain't happened yet!!!)

John




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#2 96lt1ss

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Posted 22 November 2003 - 11:42 AM

There is a member of this board who has developed a kit that will work but does not have them available for sale yet due to some legal issues. Keep checking back and hopefully we will all be able to get them soon...
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#3 Sgt

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Posted 22 November 2003 - 09:42 PM

Tommy--
Here's an earlier post that tells all about the spring kits. We are still waiting. Below is link:

http://www.machinegu...0&hl=spring kit

P.S. If Dave is reading this, could you give us an update. I think there are a bunch of members ready to send you money. Thanks
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#4 96lt1ss

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Posted 23 November 2003 - 05:12 AM

I have communicated with Dave several times today he has stated there is light at the end of the tunnel and has 30+ spring kits that will be available very soon.

Keep watching for the post as it shouldn't be much longer, personally I don't think they will last long.
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#5 Sgt

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Posted 23 November 2003 - 08:01 AM

That is fantastic. It will put a whole new feel to the Kahr experience. I also trust Dave's knowledge and redesign.
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#6 Zamm

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Posted 23 November 2003 - 09:57 PM

Dave, oh Dave, I must, I covet a set of your springs!!! I'll send you the money now!! I'll give you a hundred billion million dollars for them!!! smile.gif
If I don't get a set, I'll take my old westy set out and hang myself with them!! With the tension in them, they should easily support my dead weight!! smile.gif
OI!
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#7 Sgt

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Posted 23 November 2003 - 11:27 PM

Calm down, Craig! You are under too much tension.
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#8 Zamm

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Posted 24 November 2003 - 08:19 PM

Ralph! Doogh! Ya got me!
smile.gif
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#9 Whiskey Brother

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Posted 24 November 2003 - 08:22 PM

Wouldn't weaker springs cause the bolt to perhaps open too soon, and cause a lot of battering to the gun?
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#10 Sgt

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Posted 24 November 2003 - 09:29 PM

If I'm not mistaken, I believe Dave is a spring engineer, or at least does a lot of analysis on them. I'll bet he's considered that as one of his parameters, along with a buffer design. Maybe PK can answer this one, if Dave is not around.
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#11 PK.

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Posted 24 November 2003 - 10:31 PM

Whiskey Bro. is right on. The reduced power springs will have to be combined with a new and effective buffer design. The bolt velocity will be increased by use of the new springs.

I spoke with Dave about a month ago; he had discovered a problem with his buffer design and was working to correct it. We all wish him success.

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#12 Dave Janowski

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Posted 26 November 2003 - 01:25 PM

Hey I was reading!
OK My buffers were too thick SO I machined them thinner, and am doing some more testing.

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#13 Dave Janowski

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Posted 26 November 2003 - 01:32 PM

OK this is pissing me off! hitting wrong keys and posting weird posts!!

I dont think there will be too much troubles with the increased velocity of the bolt here is my reasoning:

1. The tension of my springs COMBINED is still stronger that that of a factory TSMG M1A1, a PURE slam fire machine.
2. The thickness of the West Hurley semi is MUCH thicker than a factory 1928, or even a M1A1 for that matter, plus I am adding a impact resistant buffer system, that should help.
3. As for opening too soon I dont see how that can happen, a M1A1 is a direct blowback mechanism EXACTLY like the semi and needs chamber pressure to cycle the action, a 45 is a 45 if it will cycle the FA bolt with less tension than I have already, there should be no problems!

Any how I am going to do a few more tests I have about 30 or so that will be ready SOON guys I know this has been a long wait thanks for your support.

I will keep you all posted

Dave
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#14 Zamm

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Posted 26 November 2003 - 04:11 PM

Dave,
We are all silently working with you, positive energy and all that!
Cool...
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#15 PK.

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Posted 26 November 2003 - 04:58 PM

Donít get mad Dave, you and I have talked a lot about this and nothing I said is disparaging.

I am not worried about the bolt opening to fast but the bolt velocity will be higher if the spring load is reduced (the stated goal). You canít compare spring rates/loads between the m1 and 27a1 because the m1 has a much heavier bolt than the 27a1.

The key is the buffer.

I shared what you told me because there has been so much guessing going on with no response of fact. To me, I would rather know that the process is evolving.

Everyone here (myself included) is on your side and want to see this work. It is an engineering project and will take time to sort out and make right. You have expressed commitment not to put these out until they were right and that is admirable and as it should be.

I would suggest to the board that every one back off and give Dave the room he needs; when he is ready heíll let us know.

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#16 ThompsonCrazy

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Posted 26 November 2003 - 05:01 PM

Just think positive waves....like Oddball. blink.gif

"Woff Woff, That's my other dog impression"

BTW "Smoking is the futures misfortune" and "there is gasoline all over zis place" wink.gif
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#17 Dave Janowski

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Posted 26 November 2003 - 06:19 PM

PAUL!
YOU KNOW I RESPECT ALL OF YOUR INPUT 100%!
I was not even criticizing what youthink, I repect it and incorporated it into my design!

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#18 Dave Janowski

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Posted 26 November 2003 - 06:21 PM

DAMN IT

this thing is PISSING ME OFF!!!

Guys not long now, I SURE hope all this works out if not I will feel like a total butt hole!


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#19 Dave Janowski

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Posted 26 November 2003 - 06:58 PM

GUYS!

I AM NOT pissed at ANYONE on the board! I am pissed at my computer! It keeps posting incomplete posts!!!

Dave
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#20 Sgt

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Posted 26 November 2003 - 07:36 PM

Dave--
Please feel no pressure from our inquiries. We are just tickled to death that someone with credibility is attacking this problem. Yippeeeee!
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