Ed Huntress wrote:
On Thu, 21 Feb 2013 13:20:35 -0500, "Steve W."
wrote:

RogerN wrote:
"Steve W." wrote in message ...

snip
Depends on the type of automatic action. If you're talking about an M-16
then you have it almost correct. If you leave the disconnecter out you
would get single shot. Reason being that the hammer would simply follow the
bolt and ride it.

http://www.xdtalk.com/forums/ar-talk...ar-15-m16.html

The regulated part of the auto version is actually the auto-sear unit on
the right side in the lower animation.

--
Steve W.
That's what I was wondering about, it would seem to depend on how fast the
bolt gets out of the hammer's path, so you have the bolt going pretty fast,
the hammer going a bit faster as more bolt clears, then the bolt coming to a
sudden stop, that should cause the hammer to have an impact on the firing
pin but maybe not enough to fire. I haven't got the animation to load yet
(slow internet) but I thought it would be better if the hammer was held back
until the bolt was forward.

RogerN


Bolt speed doesn't make a difference in this area. The hammer would
still ride it down without enough force to set off the primer.

The hands down easiest auto to make would be an open bolt design. On
those the firing pin is fixed on the bolt face. You cock it by pulling
the bolt back and latching it on the sear. When you pull the trigger the
spring slams the bolt forward, as it moves it strips a round out of the
magazine, chambers it and just as the bolt closes the firing pin hits
the primer and the round fires. The recoil slams the bolt back to repeat
the cycle. The cyclic rate is VERY high. You can slow it down using
heavier bolt weight, gas porting to bleed off some pressure and playing
with the spring weights.

The easiest "conversion" candidate would be a blowback operated action.
Not much to do to get them to work.

As in the case of my 57-year-old, heavily used High Standard
Supermatic .22. When the sear eventually wore over, I was treated to
an eight-or ten-shot burst, which ended up pointed almost at the range
ceiling and which stopped the firing by everyone else at the range,
for an agonizing minute.

It sure was quick. Brrrrrpp! g


Yep. Unregulated auto-fire can really burn up ammo (and barrels!)



--
Steve W.