Tuning FX Impact barrel stiffener options ?

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bigHUN

bigHUN

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Jan 16, 2020
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Speculating for now, I don't have any of these, not yet, I am just trying to predict what can go wrong.
First of, I was not a big fan of these barrel stiffeners for MK2, either the Front Support Block only can maybe work, but the Extended Upper Rail integrated clamp I am considering even the worst possible - if the alignment is off - then the scope alignment will be off as well.
Without these stiffener gizmos and ordinary - pellet Impact functions just well, but mine got some heavy high power upgrades.
I just decided not getting the Pantera for long range shooting and I will be converting the MK2 back for heavy .25 slugs.
Since I have a shroud+barrel tuner already and not really like the idea replacing it again with a new tube....
What other options are known to be working great?
 
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Yes, I am well beyond replacing orings to Buna 90, done that two years ago.
Also I am aware of rounding errors what misalignment parts can do, for this same reason I didn't got it yet. I am same not a fan of tightening that screw in the Rear Block, the best would be drilling both sides and just a cone and use two tip point setscrews (or steel balls), not too tight but only to have them there.
 
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@bigHUN. When you are saying "big power", that would probably take a 600mm option off the table?
I do have the FX Barrel Tension Block on both my M3 and MKII, albeit, with 500mm and 600mm respectively. Stiffness has greatly increased over stock. I have also added the full top rail replacement from AirMarksman (short) which has added another level of stiffness to the whole of the gun as well. I totally agree with your Huma concerns about the top rail clamp+ barrel clamp. Not a fan.

Patrick
 
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MongooseV8 said:
....The Huma rail ...
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I gave you a thumbs down because you answered like people in the amazon reviews just to add up the stars ... "shipping was fast, packaging great, but I haven't try it yet".
The original FX upper rail have adjustability for a reason, shoot a group of 5 at a vertical line at 20 and again repeat at 100 and you will see.
 
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Airgunmann said:
.....I like the way it lines up the whole gun
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Yes, if lines up it is great.
I have already upgraded the shroud once to a barrel tunner, now to replace again to a CF sleeve, me just better replace only the Front Block with a clamp. Also, that is actually stiffening the outer barrel tube only, and from my standpoint is that - 14mm OD x 600mm long alu tube or CF tube - nah not much difference, the inner liner is still floating. How to stiffen the inner liner? To stretch it like a guitar string....... !
 
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bigHUN said:
I gave you a thumbs down because you answered like people in the amazon reviews just to add up the stars ... "shipping was fast, packaging great, but I haven't try it yet".
The original FX upper rail have adjustability for a reason, shoot a group of 5 at a vertical line at 20 and again repeat at 100 and you will see.
Click to expand...
I don't call a bad design adjustment maybe it were more prisice or more room than just the screw slop
 
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bigHUN said:
I gave you a thumbs down because you answered like people in the amazon reviews just to add up the stars ... "shipping was fast, packaging great, but I haven't try it yet".
The original FX upper rail have adjustability for a reason, shoot a group of 5 at a vertical line at 20 and again repeat at 100 and you will see.
Click to expand...
If thats the case you thumbs downed the wrong post lol. Either way have fun with your echo chamber and welcome to the block list. I was just trying to help you by adding my thoughts, followed up by a genuine question to you. Thats called a discussion. This forum has a real attitude problem not found on others in the same vein. Shame.
 
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MongooseV8 said:
If thats the case you thumbs downed the wrong post lol. Either way have fun with your echo chamber and welcome to the block list. I was just trying to help you by adding my thoughts, followed up by a genuine question to you. Thats called a discussion. This forum has a real attitude problem not found on others in the same vein. Shame.
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OK, don't be so sensitive, no need...I gave you a thumbs up as well. Feel better?
 
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2L8 said:
@bigHUN. When you are saying "big power", that would probably take a 600mm option off the table....
Patrick
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Last season the entire year I was shooting slugs only from my MK2, I made the modifications all DIY not many new parts needed, but mostly re-machining the airpath. And BTW this how the "powerblock" was born the same way.
From a .25x700mm SH liner I probably shoot about 5-6K slugs, and tuned along the time.
The max fpe what I tried was a 44g ZAN 1050 fps @145 bars on the Reg and still about 5.5mm travel on HS. With that same tune just swap to 46g boattails and speed was 1010 fps. I believe it is possible to get the 44g to 1100 but I didn't wanted to stretch the stress limits on the Impact, because the initial design was not meant to.
But something else.
I didn't like the grouping size or the scores @100 with slugs. Shooting 34g pellets at 960 same distance was way better score vs slugs.
And that could be because of the barrel whip from a higher stress.
Second....The liner cleaning interval after slugs...
 
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Airgunmann said:
It's nice that it can be changed if the original top rail is off but for that kinda money for a gun it should be straight
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OK, so I've been here and there with my MK2.... imagine you indexing your liner and a best group gets off the scope centerline ;)
You would click the turret? or you can just adjust the entire upper rail there and back all the way until you get the 5-or 20 yard and 100 all alligned to a same vertical ????
This why the FX cost that kind a money because every single screw has some function on it !!!
 
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