RTI Prophet Performance P1 fill port

[EPG]

Hi Guys,

This is the foster fitting from my RTI Prophet Performance P1 .

I removed because rifle was leaking through this port.

When I removed, there was no o-ring, but appeared to be a small piece of clear rubbery substance.

I added the small o-ring in the picture. It worked for a couple fills, but then rifle started discharging all air through this foster when bleeding fill hose after adding air to rifle.

The o-ring was a guess on my part, because it seemed there was a little groove for it at top of stem - see picture.

Questions:

Is an o-ring required? (or does the check valve seal metal to metal?

If an o-ring is necessary, what size and hardness is required?

Thanks,

-Ed

 

[jmohme]

here is what the correct one looks like.

 

[jmohme]

When mine started leaking I scrounged around and found an o ring that worked, but ordered a replacement fill fitting from RTI Arms.
here is a link to it.

Nipple Foster Valve RTI Prophet

Thread size: 1/8 bsp

www.rtiarms.shop

You might also want to check with Tony at Talon Tunes.
Amazon also.
I ordered from RTI Arms only because I could not find what the thread size was so I went for the easy route.

 

[EPG]

here is what the correct one looks like.
View attachment 583779

Thanks - I really appreciate the picture.

This time I used a 6mm OD o-ring with 2mm cross section (thickness).

My original guesstimate o-ring was too small.

30 second fix, lol. Aired her up and she’s holding air and ready for action!

-Ed

 

[Joedirt199]

The foster fitting should be universal and not need to order expensive parts. The clear oring is the right one.

 

[EPG]

First card I shot after airing her back up... I'm stoked. This is the 2nd 198 40-Masters I shot with her in the last two weeks.

Who says you need the latest and greatest when the Prophet P1 can be so accurate at 40 yards (and longer).

 

[igolfat8]

Great shooting Ed.

 

[Shortcut]

That is some nice shooting with a nice rifle.

 

[jmohme]

The foster fitting should be universal and not need to order expensive parts. The clear oring is the right one.

True, but none of the Foster fittings I had in my box of spares had the right thread, so I borrowed an o-ring from one and ordered a replacement Foster from RTI Arms for next time.
Not really expensive either. About $20 for two of them, and I know they have the correct thread pitch. When I got back from my trip, they were in my mailbox.

 

[jmohme]

First card I shot after airing her back up... I'm stoked. This is the 2nd 198 40-Masters I shot with her in the last two weeks.

Who says you need the latest and greatest when the Prophet P1 can be so accurate at 40 yards (and longer).

View attachment 583932

View attachment 583933

Very nice. The Prophet is a great gun. I love mine

 

[EPG]

Great shooting Ed.

Thanks. This is my first card of today... Highest X count I've ever got on 40-Masters with Prophet .22 LR (P1)... although one point from tying my 198 highs with it. The JSB 20.83s at 930fps + the Neil Clague moderator (that I never got around to using till lately) seem to have improved my old P1 - cause it can't be my shooting, lol.

That was 5 straight 40-Masters of 196 or better with the P1. My second card was a 193 today - so streak over - wind got me on last two rows. However, I shot 5 straight nice Xs from 3a through 5a&b and 6a&b - I was like "damn, I'm feeling good" - then the breeze kicked up and confused me on last row and killed my super hot streak. I did nail Xs on the 2 sighters I took before the 197 (white dot left of top row) and single sighter I took before card 2 (right of row 1) - gotta love Xs at 40 yards !

-Ed

 

[jmohme]

193 is still nothing to be worried about. Still a good card.

I was shooting mine yesterday. Not paper though. My cucumber crop is so overwhelming this year that I just set up over ripened ones at 35 yards and exploded them with .25 36.2 grain Nielsen hollow points.
I hate letting produce go to waste.

 

[bchannell]

You guys are killing me with those Prophets. I've yet to find someone who isn't amazed at how they shoot. Some grips about growing pains as they came out with new models, but no gripes about accuracy.
I saw a LR barrel advertised and thought I'd buy it because a Prophet is hopefully my next rifle, but after seeing and talking to RPB barrel owners, I'm sold on them. A P3, some slugs and I'd be in heaven!

 

[EPG]

You guys are killing me with those Prophets. I've yet to find someone who isn't amazed at how they shoot. Some grips about growing pains as they came out with new models, but no gripes about accuracy.
I saw a LR barrel advertised and thought I'd buy it because a Prophet is hopefully my next rifle, but after seeing and talking to RPB barrel owners, I'm sold on them. A P3, some slugs and I'd be in heaven!

Hi Bob,

My Prophets (both P1s) are rifles that I’ll describe as “easy to shoot accurately”.

I’ve got an extensive collection of 20+ high end PCPs from RTI, Daystate, Weihrauch, FX, etc…. so I’m basing that description after shooting a lot of different rifles.

My targets for those 30 & 40 yard challenges have a .125” (1/8) inch diameter ten-ring. I’m shooting at over 40 ft/lbs (20.83g @935 fps) with the Prophet P1 .22 LR. The rifle is extremely docile - its quiet and doesn’t recoil or move. I have seen VERY FEW rifles that are so docile to shoot - and almost none at 40+ ft/lbs.

The trigger on the P1 is WAY better than an FX trigger - I currently own 6 FXs - its a nice two stage that you can set up at 5-6 ounces out-of-the-box (no trigger job required).

Its a really nice rifle to shoot.

-Ed

 

[Vetmx]

You’re probably going to cook that grab bag oring. It needs to be polyurethane. In the meantime, fill the gun as slow as your excitement levels to get back to shooting can handle. It will last a while if you don’t smoke it.

 

[EPG]

You’re probably going to cook that grab bag oring. It needs to be polyurethane. In the meantime, fill the gun as slow as your excitement levels to get back to shooting can handle. It will last a while if you don’t smoke it.

Yeah, perhaps - but I’v got at least 20 of ‘em.

If someone could please give me the specs on the poly o-ring required, I’d really appreciate it.

In the meantime, this 6mm OD by 2mm cross section o-ring works great. I can even use the EZ-Fill and it works like a charm - better than my original poly one -likely because it was damaged.

 

[igolfat8]

Ed, O-rings are generally sized by the ID and cross section thickness so I’d think the same ID as your butyl ring would crossover to the. Poly one?

 

[igolfat8]

Ed, Measure the OD of the smallest portion of the valve stem, where the O-ring sets. That will be the size of the O-ring to order plus the cross section thickness of the old one.