My pcp is dead on target at 30 yards and groups great without the moferator. With the moderator, my pcp is dead on target at 30 yards and groups great. BUT removing or adding changes the POI by over 4 inches at only 30 yards. This makes no sense to me. A small change yes but 4 inches at 30 yards is extreme. I am wondering if anyone else has a big change and WHY is the movment so large. I would say is cliping or some way misaligned BUT it shoots just as good with or without the moverator BUT with a 4 inch difference.
Moderator changes POI
- Thread starter PennyPincher
- Start date
You will see this with many rifles and many moderators. Nothing to worry about. You are adding a big weight to the end of the barrel. It is going to affect it.
If it is grouping well, it is NOT clipping. You will know because the groups will open up wide.
What rifle are you shooting?
If it is grouping well, it is NOT clipping. You will know because the groups will open up wide.
What rifle are you shooting?
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I have several rifles where the POI hardly moves at all, if at all. But one that does. The 4 inches at 30 yards does seem like a lot. If the group is unchanged in size or not much so then I guess it normal.
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Anything that you attach to the barrel will change the POI. Four inches at 30 yards is a lot, but not shocking. The barrel profile the moderator weight are variables that will affect the amount of influence. Don't worry about it, just zero and enjoy.
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My gun is an FX Dreaam lite. It groups great with or without moderator. If you guys agree it is a non issue I will just enjoy it with or without the moderator and move on. THANKS
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The closer a pellet gets to a baffle, the more pronounced the effect of pulling the pellet out of straight flight.
I cannot recall the effect name but the pressure decreases as a projectile gets very close to a fixed object.
I cannot recall the effect name but the pressure decreases as a projectile gets very close to a fixed object.
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I have a curious question.
When removing and replacing the moderator a few times in a row--
Does the POI shift remain exactly inn the same spot each time the moderator is replaced?
Hope I am asking this clearly
Edward
When removing and replacing the moderator a few times in a row--
Does the POI shift remain exactly inn the same spot each time the moderator is replaced?
Hope I am asking this clearly
Edward
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If the barrel is floated in anyway, even within a shroud and held by any o-ring, there is a very high chance you will see some sort of POI drift when adding a moderator, primarily from added barrel droop.
Heck, just tightening/loosening many guns shrouds a minor bit will change the POI.
Also, different weight moderators or removing them is changing the harmonic frequency during your shot cycle, even if it were 100% rigid.
-Matt
Heck, just tightening/loosening many guns shrouds a minor bit will change the POI.
Also, different weight moderators or removing them is changing the harmonic frequency during your shot cycle, even if it were 100% rigid.
-Matt
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Same thing happens to me when I use a clamp-on chronometer, and for free floated barrels/shrouds the slightest bit of cant and magnify how much the assembly deflects and really throw off the windage.
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On the BK and the delta wold they have the barel tensioner.
I am not clipping but my groups open up with a zero DB .30 and it is noticeable at 25 yards. Poi shift is negligible but also there too.
See if they have something like that for your gun. Also, if you have more barrel length than you really need for your purposes you could try a shorter barrel.
Hopefully I will get my answer by reading yours.
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With higher end real surpressors on real guns that is exactly what you expect, you want your surpressor clocked exactly the same way when they are put on and exactly as tight.
That is not what I am seeing with my zero DB .30. groups open and get inconsistent with each attachment and reattachment.
That's a good question, though. Very few people think of this when they buy cans of course one way around it is to never take it off I have a surefire that is direct thread and never been cleaned.
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^^^^This.
I usually attach a moderator and mark it and the end of the shroud with a paint marker. That way when/if reattachment is necessary, I just line those marks up and it's g2g.
mike
I usually attach a moderator and mark it and the end of the shroud with a paint marker. That way when/if reattachment is necessary, I just line those marks up and it's g2g.
mike
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Remove moderator, Lay kite string across barrel and shoot it. You may figure something out.
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