Or is it just more power at current hammer setting/keep same power with less hammer....
Tuning Would adding larger plenum help with reg creep
- Thread starter Uragan.25
- Start date
I understand how a larger plenum can impact tuning balance, but I don't see how the plenum capacity would affect the mechanical operation of the reg. Of course, there are many things I don't understand.
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Larger plenum will not help with reg creep. As stated a larger plenum will help with either more power at same pressure or can lower pressure to get same power as before. Depending on if the plenum is small as is. If it's not too much of a difference you won't notice much, or if plenum is plenty big already won't notice much.
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Its a prophet compact .25 going 840 with 33s at 150 bar reg. 70cc plenum.
Fill to 300 , reg stops at 150 then creeps up to 160.
Reg clock bounces down to about 135 on each shot then slowly climbs then very slowly creeps back up to 160
After about 4 or 6 shots it returns to 150.
Then works down to 140 when im at 150 on the pressure clock
Reg adjustment only done at 300 fill.
Reg cleaned and polished twice.
Im thinking the plenum is dumping too much air and slaving the reg ,, may be wrong ?
Fill to 300 , reg stops at 150 then creeps up to 160.
Reg clock bounces down to about 135 on each shot then slowly climbs then very slowly creeps back up to 160
After about 4 or 6 shots it returns to 150.
Then works down to 140 when im at 150 on the pressure clock
Reg adjustment only done at 300 fill.
Reg cleaned and polished twice.
Im thinking the plenum is dumping too much air and slaving the reg ,, may be wrong ?
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Everything you described sounds pretty typical. 300b leaning on a tiny side filling reg doesn’t make them happy. I have a bunch of 300b guns but never fill any of them above 265b. The exception is my Leshiy classic. I’ll fill it to 300b when I take it with me in the woods. It has a Huma in it and seems to handle it just fine. But that gun doesn’t have a reg gauge to fuss over so who knows. As far as big plenums go, if a RTI compact needed one, they would have put one on it. It would only cost them $5 from a production standpoint.
If your compact is a P1, then it has a conventional valve. So you get to play the balancing act with your spring tension to keep things as tight as possible over the wide pressure swing from your bottle. But since you fill to 300b, you just made that swing wider. If you have a P2 or P3, you can still play with the hammer spring by adding a little to cover those first 6 shots. Then it is what it is.
If your compact is a P1, then it has a conventional valve. So you get to play the balancing act with your spring tension to keep things as tight as possible over the wide pressure swing from your bottle. But since you fill to 300b, you just made that swing wider. If you have a P2 or P3, you can still play with the hammer spring by adding a little to cover those first 6 shots. Then it is what it is.
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I would also like to add, a RTI compact is not really a 34gr slinging gun. A standard length RTI will do it in its sleep with a great shot count that doesn’t require a 300b fill. You are trying to operate that gun outside its wheelhouse. So one thing leads to another and there are issues.
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Its a P2. All you say seems logical. I didn,t realize that 33s would be too heavy but thinking on it now, it does have a 1:20 twist rate that basically says 25g.
Thanks for the " wake up call "
.I,ll reconfigure
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1-20" is a great TR for 33 gr. If you have a 500mm barrel, your rifle setup is no different than my marauder in terms of barrel, shooting 33's and many people are launching 33's wonderfully with 20" barrels and a 1-20" twist...
Not sure where the idea that the RTI P2 compact standard isn't able to shoot 33 gr came from but that is a rather silly assumption imo...
-Matt
Not sure where the idea that the RTI P2 compact standard isn't able to shoot 33 gr came from but that is a rather silly assumption imo...
-Matt
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Also, OP is having issues not related whatsoever to pellet weight currently, these are regulator issues that won't simply resolve themselves by shooting a lighter pellet, what line of thinking is even going on?
As someone else suggested, if you don't already have one, try a huma regulator it may perform much better than RTI's, however its a gamble. But there is no reason your gun can't shoot 33 gr at 150 bar all day long with 300 bar fills...
-Matt
As someone else suggested, if you don't already have one, try a huma regulator it may perform much better than RTI's, however its a gamble. But there is no reason your gun can't shoot 33 gr at 150 bar all day long with 300 bar fills...
-Matt
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The assumption is not an assumption. I own the gun and a stack of barrels. A standard P2 shoots 33.95’s as fast as you would want them to go at 105b. And with only filling to 250b, there is still a pressure swing with the reg. Just not as dramatic as his filling to 300b. I’ve also used the Huma on my other RTI. That reg wasn’t exactly rock solid until I did some work on it. But it’s not a tweakers reg. The guy I sold that gun to is a set it and forget it guy so he got the Huma. He‘s had it a year and said it remains solid. A compact RTI is just a happier gun if you stay away from heavy projectiles and slug settings.
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Setting at 105b is further away from 250b or 300b than 150b, the further away your set pressure is from fill pressure the more susceptible you are to reg creep, I don't follow you but imo the issue is not pellet weight...not going to dig deeper into this as I already stated my 2c
-Matt
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Stock OEM Regulator should be able to handle 150 bar all day. You can't compare a 600mm gun or 700mm gun tune to a 500mm gun that needs more pressure to compensate. Below is a screenshot from RTI website p2 compact tech data. They don't come with 70cc and ability to do 180bar to shoot only 25.4's...heck this gun should be able to push 60-70 fpe easily all day...
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So its now set at 105 reg and filled to 260. I crept up 5b to 110 and shot down to 105 without a glitch from 825fps to 815fps useing Hades..
Weird thing is why at 155bar over setpoint of 105 it runs smooth.. but.. 150bar over setpoint of 150 itd a dog.
Yes 34s flew nice in the gun as do the Hades.
Could it be that the bottle is not true.... Stated as 300 fill but really not and its transferring it to the reg...
Has anyone ever tested various bottles to compare with manufactures claims.. ?
Weird thing is why at 155bar over setpoint of 105 it runs smooth.. but.. 150bar over setpoint of 150 itd a dog.
Yes 34s flew nice in the gun as do the Hades.
Could it be that the bottle is not true.... Stated as 300 fill but really not and its transferring it to the reg...
Has anyone ever tested various bottles to compare with manufactures claims.. ?
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The stock reg can handle 150b all day. What it can’t handle is the 300b in the tank. I’ve owned RTI’s since they were invented. Once they went to a fiddlers reg, they really started following bottle pressure. Sometimes more than the normal 4%. Back in maybe 2019 I even bent Motorheads ear about the issue. He gave me his input and that was that. I just keep letting them redesign the thing and it gets a little better each time. Plus I do a few tweaks.
You have to own the gun to understand some things. Will it or is it capable of shooting 34gr stuff? Yes. But the sound coming out the barrel tells you that you went too far. I’m sure you know what I’m talking about. Put the gun on 25gr pellets and a more conservative reg setting and it’s like a different gun. Unless you try cranking them up.
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If the REG creep it is the REG you need to look at.
Mind you, me currently shooting a .177 Two ( tube ) rifle, i have contemplated making the plenum volume a bit smaller just for the heck of it, for what i do / have i think it have plenty volume.
Regarding pressure, i was at 150 today with the two shooting 24 grain slugs pretty fast and tumbling like a SOB.
AND ! shooting 16 gr Beasts and Zan slugs very supersonic / past what a FC chrono will register on the high power airgun setting,,,,, and worst of all it still sort of worked out to 75 M.
I literally shot a hole in the 20 foot container that work as a back stop for us at 55 M
Not in one shot of course, but drilling the 1" stick in front of it in a attempt to also cut it there, much of my lead landed in the same place again and again.
Okay it is a rusty old container, But at least on the surface ( me skilled industrial painter and surface treatment ) it did not look rusty.
Fortunately it is dual layer where i shot, CUZ inside is is my friends not cheap big pond filter he need to sell to get a real man PCP.
Mind you, me currently shooting a .177 Two ( tube ) rifle, i have contemplated making the plenum volume a bit smaller just for the heck of it, for what i do / have i think it have plenty volume.
Regarding pressure, i was at 150 today with the two shooting 24 grain slugs pretty fast and tumbling like a SOB.
AND ! shooting 16 gr Beasts and Zan slugs very supersonic / past what a FC chrono will register on the high power airgun setting,,,,, and worst of all it still sort of worked out to 75 M.
I literally shot a hole in the 20 foot container that work as a back stop for us at 55 M
Not in one shot of course, but drilling the 1" stick in front of it in a attempt to also cut it there, much of my lead landed in the same place again and again.
Okay it is a rusty old container, But at least on the surface ( me skilled industrial painter and surface treatment ) it did not look rusty.
Fortunately it is dual layer where i shot, CUZ inside is is my friends not cheap big pond filter he need to sell to get a real man PCP.
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Not sure how old your rifle is and one of these other guys most likely has more insight but since I didn't see it mentioned. RTI had some problems with their regs and came out with a redesigned one for the P2 and P3. Think I saw them on AoA site and they aren't pricey.
I don't notice my current generation reg doing anything odd or out of the usual but I also have it cranked up for tackling larger critters.
I don't notice my current generation reg doing anything odd or out of the usual but I also have it cranked up for tackling larger critters.
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