DM5 efficiency problem

[M600]

my dm5 is a fat whore when it comes to air efficiency, i know its old but when i filled my stako to 3000 psi half the air is gone with only one hopper full shot.
is this normal? i dont remember it being that bad....
how can i make it more efficient?

 

[Gassy]

Search for "Tophat mod" on matrix owners or pbnation

Here

http://www.pbnation.com/showthread.php?t=1277166

 

[rayko]

Get a good ball/bore fit, and apart from setting the dwell back to stock, reseting the LPR and Hyper 2, I would also change the number 20 o-rings on the back cap and the two number 11s on the stem of the bolt.

 

[M600]

Get a good ball/bore fit, and apart from setting the dwell back to stock, reseting the LPR and Hyper 2, I would also change the number 20 o-rings on the back cap and the two number 11s on the stem of the bolt.

i did change the dwell lately that might a problem
and how would changing o rings help? not that im saying your wrong i just like knowing how things work
thanks

 

[rayko]

i did change the dwell lately that might a problem
and how would changing o rings help? not that im saying your wrong i just like knowing how things work
thanks

I learnt all of this from 2 of the best techs in the UK.

If the front 20 oring on the backcap (the end which screws into the tophat) is not sealing effectively you are increasing the size of the supply chamber. Therefore using more air per shot than you actually need to.

If the back 20 oring is leaking you are going to leak air out of the back of the marker from around the threads.

If the stem orings are not sealing it means additional air is being used for each shot as the bolt moves forward the the stem cannot seal against the back cap effectively to stop air moving into the supply chamber. Also with leaking stem o-rings, you may also vent more air out of the back of the backcap per shot than necessary.

I hope that helps?

 

[Gee Tee]

May also be worth checking for leaks elsewhere

Hose fittings, bottle valve etc...