New to me Flex .30--- Added shot strings

[mackeral5]

This one arrived today.  Berky had it listed and we made a fair deal, he shipped it promptly and well packed.  It arrived with the gauge sitting on 3000psi.   

I mounted a scope and got it sighted in at 80 yards, which is the most I can safely shoot at this time.  At some point I will put it over the chronograph, but for now I'm content with it as delivered.  The WAR LDC is pretty effective, but at some point I do want to mount something with a little more displacement such as a shogun, something from Mr Clague. 

It appears to be very accurate, but it is somewhat hold sensitive compared to my other, lower powered guns.

I assume this is a non-Cobra valve as it is unregulated. 

I've got a good bit of .30 pellets so for now it's a pellet shooter.  I could see it becoming a 24" barreled slug shooter...

Please share any pointers you may have as this is all new territory for me.

[Habanero69er]

Congratulations Mike! The Flex is on my short list of wanna get airguns.

[mackeral5]

Congratulations Mike! The Flex is on my short list of wanna get airguns.

Thanks Dave.  I'm not sure if it will be the gun "for me" but I'm going to give it a whirl.

[mackeral5]

The comment about hold sensitive....  Yes, it is slightly hold sensitive due to recoil.  However after 25 or so more shots I realized it wasn't all me.  Time for a tear down...



It's a normal style valve with approximately .25" transfer and .280ish throat.  Poppet is slightly extruded.  almost 80 gram hammer.  Hammer almost had to be beat out of the tube it was so full of gunk.  This likely had something to do with the erratic shots.  Heavy valve spring with hammer in at least 1/4 inch of free flight. 

You'll see a 13ci paintball tank screwed into the tank block, this was a test fit/mock up.  I plan to put one of my 500cc  4500psi tanks and regs on it.  I believe it will seal up with the oring positioned like the OEM flex bottle. 

I don't plan to make any permanent mods so the gun can be returned to OEM form should it not be a good fit for me and I opt to sell it.

Here is a simple mod plan:

1)  peek poppet with 2mm stem
2)  500cc 4500psi bottle reg'd to 2200psi (I think that's where it's currently at.)

I'll see where this puts me, I may add a Cobra chamber as well. 

[Dairyboy]

You gotta great gun there! As you've found out the .30 airguns can be hold sensitive as I've learned from my personal guns like a RAW HM1000X .30 and my WARP COBRA .30. however once you learn them the accuracy is outstanding! I lubed my pellets with the WARP and made great accuracy into amazing accuracy

[Kinetic45^]

Jim Gaska is a very nice guy and his contact info is on the Wicked Air Rifles website.
He can provide you with spare parts and such and has always charged me a super fair price for my parts I ordered from him and work I have sent him.

He's working a LOT of hours on his main job and doing WAR stuff just part time in the cracks so can't always answer the phone at that moment, but he does answer back as soon as he can. Or shoot him an email.

Also, some parts have evolved and there might be an updated version so ask on that too.

[mackeral5]

Thanks for the info on Jim.  I'm glad to know that he is there if needed.  For now I think I am fine, I just need to find a spare hour or two to spin up a peek poppet.  I will be anxious to see how the flex responds, considering the slight extrusion of the poppet and going to a harder poppet material. 

As delivered shot count was around 15 shots from 3000psi down to 2000psi.  I hope to be able to find a 30+,shot tune with the regulated tank.  If this all works I may start looking for a Cobra reg.....

[Bullfrog]

On an unregulated Flex with the old WAR valve and a 17” barrel, you ought to be getting 20 to 24 shots from 2900psi to 2100psi at 80fpe. Do you have an idea what power level its shooting at now?

Regulated (WAR regulator) with the stock WAR valve and a lighter hammer and spring, you can easily tune the gun for 30-35psi per shot at 74-75fpe for a bunch of shots between a 3600psi fill to the 2200psi reg setpoint.

[Bullfrog]

BTW, is your trigger the 1 or 2 stage Timney?

[mackeral5]

Thanks for the tune info.  I believe Berky said the current tune was around 900fps with 44gr.  My chrony is still packed up from moving so I didn't test velocity prior to tearing down.  Based on the random fliers I saw I knew at minimum it needed a good cleaning. 

I believe the trigger is single stage, can confirm this evening.

Regarding a lighter hammer---- what hammers will fit?  I will start watching the classifieds.....i definitely would like to get away from the 80grams if possible.

[YEMX]

Any hammer for a Marauder should work... 

[Bullfrog]

At a 80fpe tune, you ought to get 5-8 more shots than you did. Sometimes the transfer port orings go out and need to be replaced. Which outdoor temp can also effect your shotcount. I often run my official shot count strings on a hot day. Can’t remember when I ran them on my original Flex.

One thing to think about before you change the hammer and add the regulator... how much flexibility (no pun intended) do you want on your power levels? You ought to be able to easily run between 70fpe and 110fpe as it is with just hammer spring adjustments you can access on the fly with a folding stock adapter. When you regulate it and lighten the hammer and spring, 90fpe will be your upper limit unless you drop in a Cothran valve.

One more thing, if you run it unregulated, never fill past 3600psi. The older Flexes like you have seem to have been made of thicker steel, but the newer Flexes for sure can’t take more than 3600psi in the tube. I ruined a tube that way in my long Flex thinking it was ok to run at 4100psi because the bottle is rated 4500psi. It pushed the valve back and dug out the retention screw slots a hair.

I think the Flex is begging for a titanium tube.

[mackeral5]

Great info Travis, especially the max fill piece.  The tube is pretty thick, but I had no idea that it was spec'd for 3500psi, I was only filling to 3000 before. 

You know I'm really not sure where I will ultimately end up with this one.  Initially I do want to see what compromise of fpe, shot count, and efficiency I can find with a regulated tune.  Later I'm sure I will also be curious about a max fpe unregulated tune. 

Next steps will be to spin up a peek poppet and screw on a regulated bottle.  No hammer or hammer spring changes, at least not initially.  Hopefully I'll have some results by this time tomorrow.

[mackeral5]

Tonight I 80% finished the peek poppet, all that remains on it is to cut the oring groove.  I also bushed down the valve body to allow for the 2mm poppet stem.  Tomorrow I will fit the poppet oring then finish making the Cobra chamber. Hopefully by mid to late afternoon I will have some numbers to share. 

[mackeral5]

Yesterday didn't quite go as planned. But I did learn a few things.

I adjusted the regulator to 2250psi, this part went as planned with no issues. it was downhill from here though.

Adding a paintball regulator isn't compatible with the 17" barrel, if you want an LDC and a 500cc tank. 



But if you have a 350cc tank you can add a paintball regulator.



I did normal things I would in any of my guns---looked for burrs, rounded edges, etc.  Once content I reassembled the tube and left off the upper so I could check for leaks. 

Upon airing up to around 1500psi it immediately starts leaking out the valve exhaust.  then something starts extruding out of the valve exhaust.  it was a clear o-ring.  I'm thinking there's no way I left a loose o-ring floating around in the gun.  Strange...

After tearing down and disassembling the valve I had a sinking feeling in my stomach....I ended up basically ruining the valve.  When I was rounding out the corner of the transition from valve throat to exhaust, I got too aggressive and got into the o-ring area where the stainless throat seals to the aluminum body.....

Chalk this one up to getting in a hurry and not properly studying prior to getting out the dremel.......

It gets better..... But it's time for church, I'll add more later.   

The short of it is I ordered a WAR Cobra valve off of Jim's website this morning.  Hopefully he has one in stock....

[mackeral5]

Well....I somewhat recovered....  I took a longshot and tried to salvage the ruined valve.  At this point I didn't have anything more to lose so I pulled out the epoxies.... It took a couple of attempts to get it right.  I got in a hurry and used superglue, it worked good enough to learn I had to go much bigger on the Cobra jet than usual.  I was having to really lean on the HST to get velocity above 800fps.  then I used JB Kwik but was still in too big of a hurry and it leaked. 

Last night i mixed up a batch of regular JB Weld and glued the valve throat/seat in with it.  This evening all looked good to go so I cleaned things up and reassembled.  Aired up to 1500, she seemed to be holding air well, it didn't even hiss while the poppet was seating. Finished assembly and aired up to 4000. 

this puts the gun in the following configuration.  350cc 4500psi carbon bottle.  Regulated to 2250psi with a paintball reg.  One of my home brewed peek poppets with 2mm stem and a home brewed Cobra chamber. Valve exhaust, transfer and barrel remain OEM Flex.  OEM heavy hammer and hammer spring.  Pellets are JSB 44's

After a bit of hst adjusting I took the first string, which was well up on the plateau--(String 2 on the chart).  20 shots at 76fpe.

I dialed it back by a couple of turns and got the nice, crisp POP of a Cobra-chambered valve tuned low on the knee.  Time for another string, this one is labeled string 3 on the chart.  This also yielded buttery-smooth cocking. 

42 shots averaging 855 FPS, 72 FPE, with an ES of 21 

Both strings were from 4000psi down to 2000psi.




I'm grateful to be at this place vs. where I was Sunday.....I was really disappointed with myself for ruining the valve. 

As a result of the valve debacle, there is a Cothran valve on the way and a WAR Cobra on order from Jim.  The Cothran will be here this week, no clue on the WAR Cobra.  At some point I will test these valves. 

Does anyone make a tank block that has more drop than this one, other than the Cobra block/regulator?  I would really like to put the 500cc  bottle back on. 

[mackeral5]

So  far she is holding air overnight with no sign of any leaks, so that's good.  I decided to put some lead to paper and see what difference a good cleaning and retuning made.  It did very well as there were ZERO fliers.  It shot like a totally different gun. 

Shots are taken while leaning against my truck, with the bipod rested on the bedcover.  Not the most stable shooting position and I'm not the best shot to begin with, but now I can say the Flex is outshooting me.  It is ready for a more appropriate shooting position. 

Distance is 85 yards, pellets are JSB 44's.  For me, in this shooting position these are decent groups. But they are close to 2" which is dismal when considering what the Flex is capable of.  The top left target has 2 mags on it, the first mag was a sighter, the second was after adjusting the scope.  The rest are 1 mag per target (7 shots).



Here's a pic with the 350cc bottle and paintball reg.



I hope to install a lighter hammer in upcoming weeks so I can reduce dwell and gain some efficiency.  For now I haven't seen any problems with my home brewed cobra valve so I won't be in any hurry to try the other valves.

[Habanero69er]

Very respectable groupings.   

[KnifeMaker]

Looks pretty darned good to me! I like that stock. What is it?


Mike

[mackeral5]

Thanks guys. 

This is the stock.  I wasn't sure about it until I realized I just needed to set it up.  After adjusting, I like it a lot.   A very precise, robust unit.

https://xlrindustries.com/collections/buttstocks