Prod mod

[DeutschKSK]

Its very simple actually, replace the hammer spring with a Discovery hammer spring. It gets rid of the very annoying lock up at higher fill pressures.

At 3000 psi I would get 584 fps, now I get 700 fps at 3000 psi. I also changed the transfer port out for a .120" as well I get 16 shots down to 2000 psi. I checked my FPS at 3000 psi it was 700s, I went upstairs shot 2 mags through came back down my fps was 740 fps at 2000 psi. I still need to mess with the spring settings but I am very happy that the lock up is no longer a problem.

I figure I'll get it down to the mid 650s or leave it alone, shes hitting very hard and accurate now. Now that I have my problem fixed I am going to call Crosman for a Mrod barrel and put that on my Prod for a little boost in accuracy (If I get a good barrel!) and perhaps a 20 to 30 fps gain.

-Matt

My indoor chrony setup / messing around with stuff area.



The original spring for the Prod, the discovery hammer spring is a little longer than this one, but "dang" the discovery spring makes one heck of a difference!

[bodybag0]

Looks like your getting good results.  Hey, where did you get the transfer port?

[RatRacer]

Thanks for this Matt. Gives me something to tinker with.

BB-
Here's the Crosman part #'s

2220-014 Sleeve, Transfer Port   qty 1
130-036   Seal, Face .260 .165 .085  qty 2

[rsterne]

What is the # 2220-014 transfer port from?....

Bob

[RatRacer]

What is the # 2220-014 transfer port from?....

Bob

P-rod
I believe it is .080 stock size.

[rsterne]

Thanks, I was wondering if Crosman "borrowed" it from an earlier gun (they often do that).... I thought it was smaller than that, because I saw one article where the guy drilled it out to 2mm, which is only 0.079".... Maybe he meant 3mm (0.118").... That seems to be a more common size when modding....

I use a 1/8" (0.125") transfer port in my Grouse Gun (2260 based) and I get 16 shots at 20 FPE with a 14.5" barrel (18.1 gr. JSBs at 700 fps).... I understand that the exhaust port in the PRod valve is smaller than that in a 22XX/Disco valve, however, (I guess because it was designed for 3000 psi)....

Bob

[RatRacer]

The ~.118 are seems where everyone has settled in.

[DeutschKSK]

I can now fill up my Prod to 3300 PSI. 16 shots from there takes me down to around 2500 PSI 16 more shots takes me down to around 1500 PSI I stop there. Not bad for all my shots being in the 700 fps range.

I just ordered an Mrod barrel from Crosman, that will get here next week hopefully.

I'll post pics once I get it!

Matt