This page will be useful for RPM owners who have done the
Autococker LPR Mod.
It will also be useful for just about any
other marker running a LPR.
This
is what I did to sweet spot my regulators. I first set my hpr to 200psi, which
is a great start off velocity, and I start the lpr at 50psi. The this is what I
did.
step1) I determine what my desired velocity is going to be, and I shoot over
the chrono with the start off regulator settings.
2) I shoot and chrono while raising the hpr, till I notice the velocity does
not raise any more.
3) I raise my lpr up 5psi
4) I again shoot over chrono and raise the hpr till the velocity does not
raise.
5) I repeat this process till I have reached my desired velocity, and then I
lower my lpr little by little shooting over the chrono till I see the velocity
drops again, then I raise it back till it regains that velocity again.
This kind of setting will ensure that both the hpr and the lpr are at the
lowest settings that achieve your velocity. The benefits of setting them up
like this is because, when you start off with the low settings, your lpr will
be allowing your ram to open the poppet a certain distance, and if the ram is
not opening up the poppet enough, then the hpr will have a harder time getting
the ball up to speed. Then when you raise the lpr a bit, which I like to go by
5psi at a time, then it will allow the ram to open the poppet up a little more,
allowing me to successfully raise the hpr and get a velocity rise. So what is
happening is I keep allowing the poppet to open up a bit more each time, so it
allows more pressure to be released to reach a higher velocity. And when you
have finally allowed your lpr and ram to push the poppet open enough, then the
hpr raising sequence will also be in since and you will have both regs set to
just reach your velocity.
And the benefits of sweet spotting them like this is because of the fact that,
because you have your lpr set only to open your poppet just enough to achieve
your velocity, and this eliminates the chance of a + in your chronoing. You won't get a spike because your lpr pressure
is not even giving your ram a chance to push the poppet open enough to get a
spike. And if you have all good 0-rings, and your regulators
are maintained properly, then you shouldn't get a drop neither.
If you set the lpr to 80psi, then what will happen is if the air flow increases
for whatever reason, the lpr will have allow that extra amount of pressure to
flow past the valve, which is when you see velocity spikes. This is the reason
why a lot of people suggest more expensive regs like the 2liter, and that is
because they do a much better job at regulating the air coming from the tank
consistently. But with my method of reg adjusting the lpr won't even give the
hpr a chance to push more air through the valve.
When I set my alias up this way with my stock ram sleeve, I found out that my
lpr only needed to be at 67psi to open the poppet enough to allow for 275fps.
And my consistency was phenomenal. It was -1/+0 at 275, and it is the same
thing with my EBPRS. I am now experimenting with a ram mod I came up with that
will assist the ram in ensuring it opens up the poppet the same distance every
single shot without any spikes whatsoever.
Below is a video of the
consistency achieved by the above process, it is not of the process itself nor
does it have sound, but it does prove how consistent a marker can be when sweet
spotted using this process.
Video
of Marker Chrono Consistency
“Everyone should keep in
mind, the better they keep their regulators maintained, the closer their marker
will be able to behave as it should. Technically this method is the best way,
but one should keep in mind that your regulators must be in perfect working
order for them to behave as they should.” ~android17ak47
Link
to the original post found in the thread on PbNation
As written by android17ak47 on PbNation.