Another Nielsen/LID

[propeine]

Quite a while ago I completed my 9mm form 1. Thread is in the forum somewhere. It had a griffin taper mount rear cap because well it seemed like a good idea at the time. I haven't shot it much because it needed a booster. So I made a booster!


True value had a huge selection of springs. Still wound up with basically what I intended and it works! Spring is 1.5in long. Preload of .4in. .080 diam wire and .875 OD

No drawings on this one just seat of the pants and napkin sketches.

[T-Rex]

Nice work.
Why didn't you allow the gas to use the space inside of the booster?
Pic of inside the taper-mount adapter?
What tolerance did you use between piston OD and taper-mount adapter?
Any blowback?

[propeine]

Nice work.
Why didn't you allow the gas to use the space inside of the booster?
Pic of inside the taper-mount adapter?
What tolerance did you use between piston OD and taper-mount adapter?
Any blowback?

I kept it sealed at the moment mostly due to crud. And the minimal expansion volume I don't think will make enough difference to make the crud in the spring area worth it.

What pics would you like? I'm happy to take more.

.003 tolerance. .626 bore and .623 piston. I imagine if I ran a whole lot of ammo through it in a hurry it might seize being that tight.

Only function tested yesterday. Doesn't seem to be too bad from a blowback standpoint. I'll video when I can get to the range rather than test firing in the garage.

[Capt. Link.]

NICE!
-CL
DD progress?

[T-Rex]

NICE!
-CL
DD progress?

Yeah, no sh*t.
I have that page bookmarked.
Thanks for bringing it up Capt.

[propeine]

NICE!
-CL
DD progress?

Yeah, no sh*t.
I have that page bookmarked.
Thanks for bringing it up Capt.

I'll post some pics of progress. Finances have slowed progress heavily. Even doing it yourself mortars are spendy...

[JulietDeltaCustoms]

Nice work! I think the form1 community would certainly benefit from a diy booster! Any way we can get you to draw up a sketch?

[propeine]

Nice work! I think the form1 community would certainly benefit from a diy booster! Any way we can get you to draw up a sketch?

Unfortunately, unless someone made a taper mount rear cap it wouldn't be of much use as designed. It would have to be built around their rear cap or redesigned to function as a standalone for say a sub gun can.

If someone needed help designing one for their own can I could certainly help with that. They aren't as complicated as people would have you believe.

[KenHo]

You did good!!! I just "barely" understand what the booster does, and no idea how to make one. Your photos are the first I've seen inside. Thanks for posting.

Ken H>

[propeine]

You did good!!! I just "barely" understand what the booster does, and no idea how to make one. Your photos are the first I've seen inside. Thanks for posting.

Ken H>

While linear inertial decoupler sounds fancy, at the end of the day its a damn shock absorber. Concentricity of the parts is important, tolerance is important and the faces need to be square. After making one, the "mystique" around them is BS in my opinion. Start around 25lb/in and then make sure the slide locks back. If it does with ease you can probably go up a little in spring tension, if it doesn't go down in spring tension.

The most important thing is to either do all critical concentric things in one operation or indicate everything back in every time. IE exterior of piston and threads of piston needs to be one op. Same with bore of the front portion, male threads to the can and female threads to hold the rear portion. Leave no room for misalignment and you'll be fine.