[OCMI_Teddy]

I'm working on a sniper project. I've been involved in scenario for years and I'm trying to build a ultra quiet marker(PSL below 55db). I'm a 3rd year Aeronautical engineer, and am designing (almost done) a custom barrel extension that'll be attached to a lapco back.

Where I need your guys expertes and experience is with the upgrades to the internals. I've seen alot of videos with people shooting their "quiet" markers, and I notice that the actual pump stroke and internals are also loud. Too much metal-on-metal contact. I've been doing my reading and I know about having lower-pressure to quiet the marker. My main concern is getting rid of the metal to metal contact.

Here's the marker.



The loudest part is this medal piece in the back that holds the bolt pin. Do they make a non-metal version of this? or one that has a rubber gasket? I basically want to get rid of as many moving metal parts as possible.

Also I'd like some advice on what valve and regulator I should look into.

[smeat]

i'm pretty sure you can get an acrylic or delrin back block (the part that holds the bolt pin), but i'm not sure how easy they are to find.

as far as internals, a light spring kit will allow you to operate at a lower pressure and make the gun quieter.

[washington (Banned)]

for a quiet gun you sure couldnt have picked a buch worse body for it. you nee more volume, unless you drill out the pump quide rod. even then you may not get enough volume

[XxCubakkaxX]

i think they make a rubber pad that goes on the front of the back block, where it hits the frame, that way u wont get that metal ping sound everytime u pump, if u cant find any for sale, im sure u can buy some rubber that u can cut. just dont make it too thick otherwise the holes wont match up and ur velocity will suffer

[OCMI_Teddy]

Washington: I'm on a tight-ish budget and I got it for $30. What do you think a reasonable estimate would be for me to get the pressure down to?

[XxCubakkaxX]

actually i had plans for a pump gun made entirely out of jello, but there was a leakage issue.

[washington (Banned)]

Originally Posted by OCMI_Teddy

Washington: I'm on a tight-ish budget and I got it for $30. What do you think a reasonable estimate would be for me to get the pressure down to?

if you drill out the guid rod to turn it into a volumizer, a high flow valve, lighter springs and a heavy hammer. you should be able to get 200 psi

[AllThingsEmpire]

Originally Posted by XxCubakkaxX

actually i had plans for a pump gun made entirely out of jello, but there was a leakage issue.

i lol'd

[OCMI_Teddy]

Originally Posted by washington

if you drill out the guid rod to turn it into a volumizer, a high flow valve, lighter springs and a heavy hammer. you should be able to get 200 psi

the guide rod is already hollow. And when I blow air into the regulator port it only comes out the guide rod hole when cocked.

[Aero$mitty]

Originally Posted by washington

if you drill out the guid rod to turn it into a volumizer, a high flow valve, lighter springs and a heavy hammer. you should be able to get 200 psi

If the people of ST could see how smart you really are they would run you out.

[washington (Banned)]

Originally Posted by OCMI_Teddy

the guide rod is already hollow. And when I blow air into the regulator port it only comes out the guide rod hole when cocked.

the gui=de rod for the pump kit is already hollow? thats odd, mst are solid

Originally Posted by Aero$mitty

If the people of ST could see how smart you really are they would run you out.

ha thanks

[EvilAuthorityX]

Originally Posted by OCMI_Teddy

the guide rod is already hollow. And when I blow air into the regulator port it only comes out the guide rod hole when cocked.

i am under the impression that you dont know what a guide rod is.

air shouldnt be coming out of the guide rod hole unless the guide rod is removed or leaking

[OCMI_Teddy]

Originally Posted by EvilAuthorityX

i am under the impression that you dont know what a guide rod is.

air shouldnt be coming out of the guide rod hole unless the guide rod is removed or leaking

it was removed, I was refering to the hole the guide rod screws into

[washington (Banned)]

with out a guide rod it will leak all the air out cocked or not.

[QmarcesQ]

Originally Posted by OCMI_Teddy

The loudest part is this medal piece in the back that holds the bolt pin. Do they make a non-metal version of this? or one that has a rubber gasket? I basically want to get rid of as many moving metal parts as possible.

Also I'd like some advice on what valve and regulator I should look into.

if thats the loudest part just install a rubber gasket or buy the delrin back for it and that should eliminate the noise

[cww516]

if you're talking about the quacking sound, that's still there with a delrin back block, albeit maybe not as much. i tried putting some electrical tape between the back block and the body to see if that would help any and it didn't, so there's one more thing to not bother trying.

[R3L]

Derlin venturi bolt with derlin pullpin
CCM derlin backblock
light springs
cover the gun and the top part of the frame in Dynamat

Low pressure is quiet, but higher pressure with an obstructed boltface is quiet too, i.e., Phantoms.

The hamer/sear interface is metal on metal. Not sure how to make it more quiet, that's why I'd muffle it with damper material.

Maybe a e-frame would be quieter? Oh MQ valve too!

[OCMI_Teddy]

Originally Posted by R3L

Derlin venturi bolt with derlin pullpin
CCM derlin backblock
light springs
cover the gun and the top part of the frame in Dynamat

Low pressure is quiet, but higher pressure with an obstructed boltface is quiet too, i.e., Phantoms.

The hamer/sear interface is metal on metal. Not sure how to make it more quiet, that's why I'd muffle it with damper material.

Maybe a e-frame would be quieter? Oh MQ valve too!

Isn't the MQ valve electronic? How does that work with a pump?
How much better is it than say a Rat valve? I don't have alot of money to use on the valve, but if it's worth the price tag I may get it.

I think for the back part I may just grind it down and replace the removed material with a soft rubber.

[washington (Banned)]

it is electric and cost a pretty penny at about 100+ and you need an e frame as well.

[OCMI_Teddy]

Originally Posted by washington

it is electric and cost a pretty penny at about 100+ and you need an e frame as well.

Oooook, I think I'll just go with a tornado valve. I'm going to be ordering a reg soon.

Also would making a larger guide rod (thus allowing a higher volume) be a good idea so I can lower the pressure even further?

Once I get the marker working I'll post up the sound levels & PSI with stock parts, then put in the LP stuff and barrel extension to show you guys if there was any significant improvement.

Any recomendations for a reg?

[bgmaninjersey89]

sidewinder or CP