Hand Cannons anyone?

[mackeral5]

I had almost forgotten about this particular combination of Legos.... I've posted it before, a couple of years ago I believe.  It has been scattered in my parts bins for a good while.  Recently I got the urge to put it back together.

This is one of about a half dozen different pistol/carbine configurations this kit can be configured for. Not pictured are the 12" and 16" barrels, tube extension, AR buffer tube adapter/stock and a few other odds and ends.

This one has no real use other than being loud, obnoxious, and giving reactive targets a pretty good thump.



Gen 1 Mrod /Brod tube
B&A breech
Prod trigger assembly with raised sear,
Cothran valve, MDS hammer with light spring
9" TJ's 1:26 .357 barrel.

Does 3 shots with JSB 81gr 680fps, 615fps, 580fps

If you have any to share please do show and tell.

[Madd Hatter]

I have been wanting one of Don Corthran's .457 pistols.

[Motorhead]

.25 cal PP700
Huma reg set back within air tube yielding more plenum than oem.
Valve work and port changes .... healthy !!!

[Spacebus]

.25 cal PP700
Huma reg set back within air tube yielding more plenum than oem.
Valve work and port changes .... healthy !!!

That looks like a lot of fun. I need to get my .25 cal Bandit barrels cleaned up.

[jmohme]

I have hand cannons, but they burn powder.

[Hawkeye51]

NICE.... do you have to wear a wrist brace to shoot it?

[Madd Hatter]

I didn't when I was shooting.223 but mine had a 14" barrel. Now back to airguns!😏

[Mr.P]

A .357 evanix rex p is the closest thing in my stash.

[avator]

Yes, my hand cannons don't belong on this forum either. 

[mackeral5]

Keep em coming...

Here is another configuration of the gun I started the thread with.  It becomes a bit more useful like this.



I used learnings from the GTA community's Simplified Balanced Valve development to modify a stem/poppet for my Cothran that allows for it to be tuned via hammer spring tension and produce a bell curve.  Without bogging this thread down with those details, the foundation of this modified stem is 3 things.  1) Change the seal to delrin which is more resilient than the soft nylon Don designed the valve to use.  2) remove the rod from the stem, this causes the valve to close violently, hence changing the sealing material to delrin.  3) enlarging the stem vent.  It's a bit more complex than that, but that is the general idea.

This results in a very miserly valve, yielding a very flat shot string that can be moved up or down in energy by dialing in/out HST. 

On a 2800psi fill, which is all I have in my tanks right now, it will get 8 shots within 17fps of each other.... Not many unreg'd big bore PCP's will shoot that flat across 1500psi  pressure range



12" barrel with a bored out Koi. it is extremely quiet for a 60fpe hand cannon

[Gippeto]

Was handed a chunk of .32 barrel and the loan of a CB shot shell breech and told to "build something". Can't remember exactly when, but it's been a few years now lol. 1" tube and internals and one of my earlier attempts at rust bluing. Shoots .310 round ball, 6 shots to a 2000psi fill. String peaks @480fps to keep it Canadian legal. Still lots of fun though.



2540 put together with a chunk of GM Marauder barrel and some other bits. Has not been used since I retired my hipacs...built a better mouse trap and will get to play with it again once the weather warms up. 





Al

[moorepower]

I might just have enough parts other than the Prof grip to build a .30 cal version! I even have a sear made for the MRod tube thickness.

[mackeral5]

Was handed a chunk of .32 barrel and the loan of a CB shot shell breech and told to "build something". Can't remember exactly when, but it's been a few years now lol. 1" tube and internals and one of my earlier attempts at rust bluing. Shoots .310 round ball, 6 shots to a 2000psi fill. String peaks @480fps to keep it Canadian legal. Still lots of fun though.



2540 put together with a chunk of GM Marauder barrel and some other bits. Has not been used since I retired my hipacs...built a better mouse trap and will get to play with it again once the weather warms up. 





Al

I fondly remember reading one of your previous posts about that .32.  The rust bluing looks great.

At some point will assembly another configuration (or 6, lol)  that is based on the Gen 1 Mrod AR buffer tube adapter you made me. 

[Rob M]

20200130_161959_HDR (1) by murphyrobert9, on Flickr

ive made a bunch , this was roughly 45fpe in 9mm



this was a p17 , it was 30 cal at one point

20200112_091405 by murphyrobert9, on Flickr



17fpe i think

one more , not completed, 47fpe
20230202_201306 by murphyrobert9, on Flickr