PRod transfer port upgrades

[Bigragu]

I’m curious to know if anyone has found or used a plastic or PTFE type of tubing as a size upgrade to the PRod transfer port. It’s been used on the Marauder rifle, and curious if the PRod is welcome to that upgrade.

If it has been done, please advise on a material type, ID/OD size, and your results to that upgrade. I’ve been reading a lot on archived forums and seems most folks also drill out the transfer port entry into the barrel to 7/64”.

Thank you

[rsterne]

7/64" (0.109") seems small for a barrel port.... On a .22 cal you can go as large as 11/64" (0.172") without causing pellet loading issues, providing you carefully deburr it on the inside.... I usually make my .22 cal barrel ports with a #19 drill (0.166")…. BUT I have never worked on a PRod....

Bob

[Bigragu]

7/64" (0.109") seems small for a barrel port.... On a .22 cal you can go as large as 11/64" (0.172") without causing pellet loading issues, providing you carefully deburr it on the inside.... I usually make my .22 cal barrel ports with a #19 drill (0.166")…. BUT I have never worked on a PRod....

Bob

The largest aftermarket TP for a PRod that I have found is .140”. It is noted that to use this size of a TP, the PRod must be regulated. If this size is chosen, and regulating not added on, can that greatly affect the performance of the pistol in a negative way?

Bob, is it safe to assume that when choosing a TP upgrade, that the size of the TP’s inside dimension dictates the the drill bit size?

Still awaiting responses on anyone using plastic type TP’s.

[Wayne52]

Drilling out the stock port to .140 leaves a good shoulder still on the transfer port, Rocker1 David has been making them .160 but he said really you don't need all the power plus when you drill them to .160 it will take the shoulder out.  I opted for .140 myself because they seat good with the shoulder on them I think.

[Bigragu]

Wayne, what are you using for the transfer port duct?

[rsterne]

You will obviously be limited by the size of the transfer port.... Augie mentioned the barrel port, which is what I responded to.... However, there is no point in making the barrel port larger than the transfer port ID....

Going to larger ports will increase the power, but reduce the shot count.... Most Crosman barrels are drilled to 0.132-0.134".... I don't know about the PRod.… However, 0.109" seems pretty small to me.... unless you are looking for shot count over power....

Wayne, if you back off the hammer spring just a whisker you will lose a bit on peak power, but tighten up the ES.... Basically you will add one shot at the beginning, and eliminate the low power shot at the end.... JMO....

Bob

[Wayne52]

Augie I used a 9/64 drill and drilled out the stock transfer port and barrel port on mine.

[Wayne52]

Bob I just wanted to crank it up for that chrony string, it was right after I put the SS valve in it and I wanted to see what it would do.  I've got it toned down a lot from that string now but it's still shooting those BBT's great.

[Bigragu]

Augie I used a 9/64 drill and drilled out the stock transfer port and barrel port on mine.

Thank you, Wayne

[Bigragu]

You will obviously be limited by the size of the transfer port.... Augie mentioned the barrel port, which is what I responded to.... However, there is no point in making the barrel port larger than the transfer port ID....

Going to larger ports will increase the power, but reduce the shot count.... Most Crosman barrels are drilled to 0.132-0.134".... I don't know about the PRod.… However, 0.109" seems pretty small to me.... unless you are looking for shot count over power....

Wayne, if you back off the hammer spring just a whisker you will lose a bit on peak power, but tighten up the ES.... Basically you will add one shot at the beginning, and eliminate the low power shot at the end.... JMO....

Bob

Thank you, Bob

[screwwork]

I have used 0.160 I'd plastic tubing for transfer ports for a few years for my prod.  No leaks or issues either, barrel and valve is at .160 too.

[screwwork]

Rocker1 is making me some custom PEEK transfer ports too. I cannot wait to get my hands on them.

[Bigragu]

Will a marauder rifle transfer port work on a pistol? I have an aftermarket .160 Marauder TP

[screwwork]

Will a marauder rifle transfer port work on a pistol? I have an aftermarket .160 Marauder TP

Nope it will not work.

[screwwork]

You can buy some .25 Poly tubing .17 ID from your local hardware store, cut it to .36 long. 
Prod T port is .26 OD x .36 long, Mrod T port is .26 OD x .465 long. Lenght measured with both gaskets on so it may vary some.

Lowes
Item # 814300 Model # 98582
EASTMAN 1/4-in x 1-ft Polyethylene Tubing

[Bigragu]

You can buy some .25 Poly tubing .17 ID from your local hardware store, cut it to .36 long. 
Prod T port is .26 OD x .36 long, Mrod T port is .26 OD x .465 long. Lenght measured with both gaskets on so it may vary some.

Lowes
Item # 814300 Model # 98582
EASTMAN 1/4-in x 1-ft Polyethylene Tubing

Randy! Wow! Thank you! Part numbers, tubing dimensions, even tubing length for the Marauder rifle, which will come in handy- thank you big time!

I am coming to the realization that because I’ve depleted my play money funds I’m going to have to become resourceful with any mods till I can save up again for buy out items. Also, I’ve had to tell myself that I am keeping this pistol as a grab and go type gun, leaving the big power and steady shot count between my 30 cal Hercules Bully and my 25 cal SynRod.

I think for now along with the poly tubing TP upgrade I’ll buy maybe a .045 and a .042 spring, and save up for the SS valve or Tim Hill’s valve upgrade. My goal is to keep the velocity at or around 725 for at least two magazines worth.

[Bigragu]

You can buy some .25 Poly tubing .17 ID from your local hardware store, cut it to .36 long. 
Prod T port is .26 OD x .36 long, Mrod T port is .26 OD x .465 long. Lenght measured with both gaskets on so it may vary some.

Lowes
Item # 814300 Model # 98582
EASTMAN 1/4-in x 1-ft Polyethylene Tubing
[/quote

Randy, re read this again, and the dimensions of the length of the poly tubing is for using it with the O ring gaskets in place? Is it okay to use poly tubing w/o the gaskets, just cut the poly a bit longer than .36”?

Thank you