.38/.357 prototype

[bruski]

Cutter,

 I understand the pivoting point but there is two arrows pointing to what it says is limiting pins.

bruski

[Cutter]

Cutter,

 I understand the pivoting point but there is two arrows pointing to what it says is limiting pins.

bruski

 

 

That\'s why I put the question marks. I don\'t know.

 

The main reason for the long extractor could be , not much room needed

at the rear to clear the rim in front.

Image at 1 degree

[Sparky_NY]

I like the idea of having a positive feeding bolt rather than a pusher, this would eliminate feeding problems while another barrel is recoiling. So maybe the groove should be cut a little wider with a taper of course to ramp up the rim under the extractor while feeding. I know from my experiences while testing the prototype very well that recoil is a big problem all of the sudden compared to the rim fires. Like opening up a new can of worms so to speak. It is hard to tell in the video how much shaking and shocking the gun is going through because it is so heavy to see the actual movement.

bruski 

The raised boss on the inside of the top cover traps the ammo which makes it work a lot like a controlled feed gun.    See the pic I posted earlier in this thread of that boss on the original gats.    I used one on my 22 and it did wonders for feed reliability.

[Cutter]

Another possibility

 

Red = cartridge/rim

 

White = bolt with 1/16 flat on bottom

 

Blue = pan with pin

 

Purple = extractor

 

Allows a 5/16 hole and 1/2 degree movement gets over the rim

[bruski]

Well, here is a couple of pictures with the barrels. Had to cut the barrels down a little to remove the extractor reliefs from the other barrel plate. Now I will have to ream them with a chamber reamer to get the 357 depth back on track again. The other picture is of the food that I will feed this beast with.

bruski

[Sparky_NY]

Sure looks nice Bruski.     What are you going to feed it with after the first day?

[Sparky_NY]

 

Another possibility

 

Red = cartridge/rim

 

White = bolt with 1/16 flat on bottom

 

Blue = pan with pin

 

Purple = extractor

 

Allows a 5/16 hole and 1/2 degree movement gets over the rim

 

Thats a 5\" long extractor, right?      There would be a 4:1 reduction in spring tension or there abouts,  it would need a chevy coil spring to get enough tension at the rim.   Also, it would be so thin that it would probably flex due to the long length.        

 

Don\'t know if he has all bolts made, but Bruski\'s pictures show he already has a extractor relief cut in his bolts.     Is Bruski having problems fitting his enfield firing pins, extractor, and ejector pin groove all into the space available on his bolts?    I am guessing he is having a space problem.

 

I have a bolt design with components but not sure how it will work out machining wise.   They are long deep holes to be drilled.   I plan on trying it as soon as some long bits I ordered deliver.   I am optimistic.

[bruski]

Sparky,

 I have not started on the 5 inch bolts yet, that is a 4 incher in the pictures. I am waiting a bit on machining any extractor slots or ejector pin slots on the new 5 inch bolts. The only problem that I did have in a 4 inch bolt was where I drilled the .312 to depth for the spring pocket. It did brake through into the bottom ejector pin slot for about 1/2 an inch in length. It didn\'t look like it would hurt anything though.

  By switching to the longer 5 inch bolt, the firing pin spring pocket can be moved back an inch or so and would solve that problem if we go with the pin ejector on the final bolts.

bruski

[bruski]

Sparky,

 Do you have a picture or drawing of your bolt design that you could post here?

 

That is funny about day two.LOL

Thanks,

bruski

[Cutter]

Sparky

“That’s a 5\" long extractor, right?      There would be a 4:1 reduction in spring tension or there abouts,  it would need a chevy coil spring to get enough tension at the rim.   Also, it would be so thin that it would probably flex due to the long length. â€œ      

 

That was just a sample of a possible method.

 

Try something more like this ( image )

[Sparky_NY]

As requested.    Here is my striker assembly and bolt assembly at this point.     Things may change a bit yet but its close.    I am considering going from 1/4 to 3/16 for the striker.   Also have to study / revise the brass bushing that retains the striker into the bolt assy.   Extractor is a copy of the M16/Ar15 one, spring is from that gun (3pcs $6 from Brownells).    Striker spring is a 16lb spring from Graingers 10pcs for $15.  (18 and 20lb springs also avail if needed)

 

Files are in 2 formats,   F3d is a native Fusion 360 format and step files for other softwares.

[Cutter]

Here’s an unfinished sketch of the firing pin assembly I have in mind.

[Sparky_NY]

Here’s an unfinished sketch of the firing pin assembly I have in mind.

Looks good.    Looks identical to a scaled down version in the original gatling guns.       Bruski can probably answer this,  any problem drilling a hole 5/16 about 5 inches deep into the bolt and keeping it straight?    (cutters bolts are 6inch long)

[bruski]

Sparky,

 Thanks for the drawings. I didn\'t have any problem drilling the 5/16 holes so far. I have some split point 3/16 cobalt bits that after center drilling I drill and peck clearing the chips as far as I can with it then switch over to a bit 1/64 smaller than 5/16 and drill to the required depth followed by a 5/16 reamer.

bruski

[Sparky_NY]

!Sparky,

 Thanks for the drawings. I didn\'t have any problem drilling the 5/16 holes so far. I have some split point 3/16 cobalt bits that after center drilling I drill and peck clearing the chips as far as I can with it then switch over to a bit 1/64 smaller than 5/16 and drill to the required depth followed by a 5/16 reamer.

bruski

Thanks !        I planned similar in the cnc lathe but had worries about the drill walking with that depth.    I feel a lot better now.

 

Let me know how it goes looking at those files I posted, and if you used the step, or F3d file.

[Sparky_NY]

Back to the drawing board.     Decided to go with 3/16 shank striker pins much the same as Cutters drawing posted.      Bruski calmed my fears of drilling that deep with a hole that small.     I ordered 3/16 O1 drill rod and a couple letter N (.302) cobalt bits 6 inches long, all will arrive mid week.      Clearance issues are cured with the smaller striker shaft, the original pin ejector method and slot in the bolt will work just fine.

 

For others,  I found a source for cheap drill bits.   WWW.drillsandcutters.com    They have the long 6 or 12 inch cobalt drill bits cheap as well as other bits.    ALSO  Strangely, Walmart online is the hot ticket for the drill rod !    $3.48 each and cheap fast shipping.   (Zoro drop ships for Walmart) Go figure !

[Sparky_NY]

Correction to prior post,  I posted 3/16 drill rod and the drawing shows .218

[bruski]

Sparky,

 I used fusion 360 to open your files ok. Make sure to get drill bits with a split point and not the standard chisel pointed for your first holes drilled in the bolts. If they are new with equal cutting edges, there should be chips from both flutes while drilling.

  I like your drawings, you have the Fusion 360 working for you very well. The strikers look similar to the D&E type if I remember correctly and should work ok.

bruski

[Sparky_NY]

Bruski,

 Good to know we can exchange fusion files ok.        I\'m redoing the strikers right now a bit,  mostly dimension changes.    I ordered cobalt bits, split points, and a couple spares.    I will experiment when the time comes before attacking the actual good bolts.

[bruski]

Sparky,

 Are you saying that you have a pile of not actual good bolts? I would call them good learning experiences if you do like me. They started way back in about 1985 with the very first attempts with the RG-G bolts that needed silver soldering, what a mess that was for me. I must have made over 30 of them to get 10 maybe use able ones. It wasn\'t until I met up with cutter on this forum and purchased some of his one piece bolts that I actually finished that gun and started a second one.

 

  The bolt material that I used on the 4 inch bolts and will probably use on the 5 inchers also is oil hardening drill rod. Not sure how well the material is going to drill for you with the pre- hardened stuff.

bruski