The black mark on the barrel liner end, does anyone know at what orientation on a clock face it should be set from the factory when reassembling the liner? I've indexed all my barrels and found there is certainly something substantial to the way its set and tensioned by the barrel nut. My question is each barrel had a black index mark but in a different position.
FX Barrel Liner Indexing
- Thread starter Wolferine
- Start date
According to UA it is only there to ID barrel twist. Best idea I found was to do a 1/4 turn 5 shot group for most accurate position . Hope that helps my eastern amigo ! 
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Thanks for the info, I had assumed the mark was a standardized index mark to help properly realign the barrel since FX seems to encourage liner swapping and CF sleeves installation etc, but couldn't figure out their rhyme and reasoning when index testing always had the mark end up in different locations. If FX is listening to YOU REALLY SHOULD HAVE A TOP CENTER INDEX MARK ON THESE LINERS to help your customers, it's just common sense.According to UA it is only there to ID barrel twist. Best idea I found was to do a 1/4 turn 5 shot group for most accurate position . Hope that helps my eastern amigo !
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Funny cause the twist is printed on the barrel. At least mine is.According to UA it is only there to ID barrel twist. Best idea I found was to do a 1/4 turn 5 shot group for most accurate position . Hope that helps my eastern amigo !
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I noticed a substantial POI shift after I messed around with my Maverick's liner a while back. It was recommended that I go through the 1/4 turn / 5 shot exercise and WOW... I was getting 8-9" shifts in POI @ 50yds. I ordered a new liner ( this was a couple years ago ) and repeated the same exercise. The new liner only shifted a couple inches at most with each rotation. I never thought the original liner had accuracy issues so not really sure if I should consider the original liner defective or not. I was really shocked by how much the original liner shifted.
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How would they know what a top center index is? These are not tested radially, they are tested linearly.
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Same here, big difference and my liner was also marked. Think someone is blowing smoke about that mark is for only twist indentfacation.
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I index tested each barrel i had 2#, 600mm and 1#, 700mm for an Impact M3 by the following procedure- USED the mark as a starting reference point and shot groups at the same target bullseye while shifting the mark from 1 oclock to 2 oclock then 3,4,5, etc till i had shot a group from all 12 postions at the same target, while writing the clock position on the target with each group as it printed. VERY TELLING RESULT. I assumed FX factory tested of should test each barrel they put out in the same manner as it has a lot to do with point of aim between near and far targets, a barrel badly misaligned can be thought of as shooting sideways slightly out of center with the center point of the rifle and potential scope alignment resulting in a 25 yard zero requiring a right or left adjustment as well as the normal holdover to hit center at say, 100+ yards. Hope this made so sense, there is some forum threads elsewhere as to this topic that were helpful.
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That 8-9'' shift is typically what I've found too, testing them at each position as it were a clock produces something of an oval shaped clock face on a target. Indexing would be setting the barrel to the top center or bottom center on that oval test pattern, thus preventing the barrel from shooting ever so slightly sideways to the center line of the scope. A barrel that produces a shift in testing isn't necessarily an inaccurate barrel just one that requires an adjustment depending on distance. For instance a badly indexed barrel with a 25 yard zero might require a .3 mill or more windage adjustment to be on target at 100 yards shooting indoors with no wind conditions or before wind conditions are even taken into account shooting outdoors.
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The liners in ny Crown mk2, Panthera, 2x drs all had a pink line in one of the grooves at the end. The mark was set at 12 o clock
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And that from their extensive history as FX-sperts, don'tcha know
No insult implied or intended
just my c-mon sense
Edward
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My m3 barrel was marked and happened to be perfectly indexed at the mark’s 12 o clock position. Could be coincidence I guess, but I went through my barrel indexing process and the mark that was already present was perfectly 12 o clock 
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Thanks, that's good to know. Just noticed one of SKOUTS rifles can be barrel indexed by loosening the nut tightening the barrel into the action and rotating according to a clock face index on the visible outside of the barrel. Love that attention to detail.My m3 barrel was marked and happened to be perfectly indexed at the mark’s 12 o clock position. Could be coincidence I guess, but I went through my barrel indexing process and the mark that was already present was perfectly 12 o clock
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Skout was using FX liners for some time, also all my FX liners come with a red index line on the muzzle end, also you can start with that line at noon take 4 shots turn the liner to 3 then 6 then 9 watch your point of impact once there indexed properly, they shoot incredibly accurate.
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None takin It is the way it is now . But they are FXs people . The new FX USA ! If they lie its there problem not mine OK .
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Not accusing them of lying.None takin It is the way it is now . But they are FXs people . The new FX USA ! If they lie its there problem not mine OK .
Just figuring that at this point they are not deep enough in FX knowledge yet.
FWIW
They have been very helpful with me.
But like a list love, I will forever miss FX-USA
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