"Consistanly ranks in the top 10, year, after year, after year" ?
Almost 1/2 way there!
Time will tell.
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FX Lock this thread please- Discussed with Fredrik, there is no evidence of POI shift in FX barrel liner system
- Thread starter mubhaur
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Almost 1/2 way there!
Time will tell.
. Must be only AGN knows about this.
In a F1 race, if most of the top drivers drive a Mercedes year after year, then chances are alot of Mercedes are going to be in the top 10. Selling a lot of guns is down to great marketing. Doesn’t mean the product is perfect.
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With that said, if YOU were going to purchase/build a car to win a F1 race, what brand would YOU purchase/build ?
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If at the time Mercedes was the only viable option then thats the only choice. Now there are other contenders who are gaining ground. If I was a top shooter with $20K on the line, I’d be choosing a rifle that in LESS THAN 1 YEAR has taken out numerous 100yds pro competitions.
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I see a request to "lock the thread" in the title as a clear attempt to make a statement without listening to other points of view.
As a retired mechanical engineer, I respect the engineering that goes into FX airguns. I used to work with Swedish engineers in a very different field and they were very good. But a thick barrel is always, always, going to be more difficult to deflect than a thin one. A carbon fiber sleeve may help but also adds some complexity due to different thermal expansion/contraction rates. I have not owned a FX so I don't really know how much of the theoretical disadvantage translates into practical issues. But comments of others leads me to believe at least sometimes there are issues that may be related to the barrel design. I would also note that there seems to be no benchrest powder burners with thin barrels. Powder burners have been playing the benchrest game for a really long time.
Requirements for extremely high level benchrest accuracy are not the same as a truck gun called upon to precisely place the first shot from a cold barrel into the target reliably. The track record of FX guns in competition seem to prove they work well for benchrest and other competition where tuning before competing is possible and even expected. I wouldn't trust that record to address truck gun reliabiity - or any usage where tuning is not reasonably possible after transport and before shooting however. But hunting doesn't really require benchrest accuracy so maybe FXs don't shift enough in most cases to be an issue. I don't have the experience to have an informed opinion. I just see the thin barrel as an inherent weakness. All the tuning built into FX guns helps a lot, I'm sure, offset that weakness but it seems arguably better just to use a more substantial barrel.
As a retired mechanical engineer, I respect the engineering that goes into FX airguns. I used to work with Swedish engineers in a very different field and they were very good. But a thick barrel is always, always, going to be more difficult to deflect than a thin one. A carbon fiber sleeve may help but also adds some complexity due to different thermal expansion/contraction rates. I have not owned a FX so I don't really know how much of the theoretical disadvantage translates into practical issues. But comments of others leads me to believe at least sometimes there are issues that may be related to the barrel design. I would also note that there seems to be no benchrest powder burners with thin barrels. Powder burners have been playing the benchrest game for a really long time.
Requirements for extremely high level benchrest accuracy are not the same as a truck gun called upon to precisely place the first shot from a cold barrel into the target reliably. The track record of FX guns in competition seem to prove they work well for benchrest and other competition where tuning before competing is possible and even expected. I wouldn't trust that record to address truck gun reliabiity - or any usage where tuning is not reasonably possible after transport and before shooting however. But hunting doesn't really require benchrest accuracy so maybe FXs don't shift enough in most cases to be an issue. I don't have the experience to have an informed opinion. I just see the thin barrel as an inherent weakness. All the tuning built into FX guns helps a lot, I'm sure, offset that weakness but it seems arguably better just to use a more substantial barrel.
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I too am a mechanical engineer and I have read through all 11 pages of this thread. Some folks have this POI issue and some do not. This is an issue that definitely exists regardless of FX's denial. I believe the cause is simple. The sighting system is mounted to the receiver not the barrel. In order for the two to remain in line, they must clamp together via an immovable register surface and they do not on every FX platform. Please examine the system FX uses. The barrel slip fits into a female bore in the receiver. and is held in place with set screws. There must be at least some running clearance between the receiver and the barrel and even if it is small, it is not zero. That clearance is subject to manufacturing tolerances. Some guns will have a bit more than others. It is unavoidable. This issue is not rocket science. It is mechanical engineering 101.The solution is an indexed conical joint with a clamping nut. Until FX makes this design change, I for one will not buy another FX gun.. I have no issue with a flexible barrel as long as it always returns to the same place. The light barrel FX uses offers a great weight advantage over a thicker conventional barrel design. Some may prefer a stiffer barrel, but I am not one of them. FX has proven their thin barrel is accurate. The problem is the lack of consistant alignment of the receiver to the barrel.
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My stock .30 caliber liner is thin walled and is supported in the barrel of my M3 by 3 O-rings.
The Smooth Twist rifling is known to produce a varying loose/tight fit with the pellet as the pellet travels down the barrel.
My mental model of load dynamics has a 45 grain. 30 cal diabolo accelerating from 0 to 579.545 mph (850 fps) nearly instantaneously , oscillating the load on the liner in sequential points along its travel as it passes through each loose/tight area.
This load oscillation is transferred unevenly to the barrel via the 3 O-rings. This should dampen the load oscillation somewhat but I don't think consistently enough such that the pellet reaches the muzzle choke with the muzzle at the same oscillation point and orientation each shot.
I totally forgot that the barrel is slip fit into the receiver and therefore adds another load dynamic.
Thanks for your input!
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So you're telling me......that a REAL barrel made from steel of substantial diameter, mounted solidly into the receiver, might not be such a terrible idea after all?
I have not, and never will be a fan of the straw-in-a-tube arrangement. And I'd gladly take whatever weight penalty that would entail.
I have not, and never will be a fan of the straw-in-a-tube arrangement. And I'd gladly take whatever weight penalty that would entail.
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I've watched top FX sponsored shooters during 100Y benchrest comps. Since the mags they use are very high capacity they take a huge amount of sighters. This is advantageous because of the feedback in the different wind conditions. One guy I saw had a half dozen-ish loaded mags sitting on the bench and he probably shot a hundred sighters or more and scored well in the end. Usually POI shifts won't be a problem in the same shooting session.
Just pointing out one reason why the FX shooters might do well in comps. Also this is not to take away from their marksmanship skills because winners gonna win.
Though yes I'm in the thicker barrel and solidly mounted - way of thinking.
Just pointing out one reason why the FX shooters might do well in comps. Also this is not to take away from their marksmanship skills because winners gonna win.
Though yes I'm in the thicker barrel and solidly mounted - way of thinking.
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Why I enjoy my .177 <12 FPE M3 more than any of my other air rifles is that this past winter at 20 yards indoors I tuned that rifle for every weight of .177 diabolo I could buy from a 7.0 grain pistol wad cutter to the 10.3 JSB's.
I tuned each until I had the smallest, consistent 5 round dispersion E to E.
Now shooting outdoors at 25 yards I match pellet weight & tune to wind conditions.
I have started a card shooting 7.0 grain wad cutters in no wind and have changed to 9.57 grain round nose mid card as the wind increased.
The beauty of the M3 is you can adjust the tune, throw sighters with the new pellet until the gun settles and then start shooting bulls.
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Look, to each his own. The thicker conventional barrel is obviously stiffer. No question, but what you cannot definitively say that thick barrel is more accurate than either a flexible one or a thin one stiffened up with a CF sleeve. I personally do not think the case has been made to dissuade me yet. Please do not confuse the light verses heavy barrel controversy with the POI issue
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Not confused in the least about either subject. Also that it doesn't take a engineering degree to use common sense, right?! Robust action+robustly affixed barrel+robust chassis or stock, possibly some bedding=the least chance of POI shifts. Couldn't make more sense.
The weak links in a system is where failure comes about. Thin alluminum action, small grub screws, liner supported by 0rings within a shroud system, alignment issues with moderators not affixed to the barrel. Heat, cold, accidentally hitting the shroud on something, other.....= more chance of POI shifts.
Having been involved with centerfire target rifles and experiencing how stoutly built they are while also knowing I can grab the more precise ones out of the safe and hit a 1" sticker at 100Y the first shot has convinced me to shy away from the somewhat fragilely built airguns using liner systems in spite of the fact I would prefer high cap mags.
My quote "Though yes I'm in the thicker barrel and solidly mounted - way of thinking". That's why I liked my old MAC1 USFT so much. Everything has positives and negatives depending on what the intent of use is but if asked which I'd trust more for a FT competition, where there are no sighters allowed, a Impact or a USFT, there's no way in the world I'd use a Impact(YMMV).
For nearly two decades there was nary a POI shift with my USFT.
My later Gen Thomas FT has also been solid.
In contrast my 1st Gen Impact needed to be resighted in almost day to day. But I acknowledge advancements in aftermarket parts and later Gen Impacts have improved them. Though not enough to convince me to try one again.
Lastly I'll just point out the incredible precision capability the latest Gen of Thomas Benchrest rifles exhibit while progressively getting more robust every iteration including those thicker barrels the last couple years. Go research in the Benchrest forum in the thread N50@100Y to see Mike N's examples if you have doubt. Personally IMHO no other airgun can compete precision wise and granted Mike N is one of the airgun world's best Benchrest shooters so that's part of it.
As well the Red Panda seems pretty stoutly built but more bench oriented than an Impact.
I'm not much of a hunter but if wanting a lighter weight repeater I'd still prefer a Vulcan 3, Taipan, or AAA, mostly because of the barrel attachment systems.
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You can only hold a thin pipe "so" well. Try to thread it and your getting close to breaking through the material. Try to use set screws and you can crush it pretty easily. Clamping might work but even then with thin walls I think you would compress it. So then you need to add parts in able to secure it which makes it unstable. Look at firearms, even thin barrels all start out thick on the breech end. I understand that has to do with pressures they deal with as well but how many have poi problems from getting bumped or just random handling? Don't matter how good a barrel can shoot if it can't be held properly in the breech it's worthless.
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I'm going to do something I don't usually do. I'm going to throw my two cents into this thread without having read the 11 pages of posts about it. An airgun company owner is saying there is NO EVIDENCE of poi shifts with his barrel system. If there is no evidence, then why does this thread even exist? The simple and obvious as hell answer is that there IS evidence.
stovepipe
stovepipe
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Some have never experienced it I didn't when I owned my mk2 that was upgraded to pretty much a m3 with a backbone and my buddies m3 hasn't changed anything since day one after I tuned it that thing is stock pretty much every thing except I switch it to left hand for him it's always been a tack driver to though
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I made a 30 cal from a green mountain blank and fitted it to my impact it had the barrel clamp as well but even a 30 cal stainless barrel is a lot more stiff than than the fx barrel problem I had was twist rate was to fast it didn't say on ebay and it was a good price so I took a chance
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I sincerely hope with all the evidence out there you do not really believe there is no POI issue, because if you do, I have a very good deal for you on a bridge.
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