Thanks to Fang(Update)

[Mpac]

I have my 47 coil spring back in my Hatsan135 25 cal. and it's back to break in time ,I'm hitting 890fps with 20.06 grain with slight dieseling just a haze of brown smoke plus I left my long tophat in to quiet down buzzing noise and have velocity tar on my spring hop-efully this gun will settle down to 850/860 fps.Thanks again Fang I'm a happy camper.

[Mpac]

This is less than 30 shots with the spring and it's coming down a little.FTT's 20.06 grain 25 caliber.

[LAalex]

Wow Daniel, that thing is a hammer! 

Scotty

[Mpac]

Should settle down after a couple hundred shots.The gun is a beast but a smooth beast and easy to shoot not a violent shot cycle.

[WHITEFANG]

Glad to here that you are up and slamming. All those springs are as new. So you are correct, they will have to settle in.
Glad to be able to help you anytime.

Your bud
FANG

[Mpac]

This gun is amazing breaking in it's hitting 37.5 ft. lbs. and almost no smoke very little,must be the tophat I have in it gave it that extra punch.Has a low thump sound when shot not a high pow like before as soon as it stops dieseling the scope goes on.A 33 Yard shot.

[Bryan Heimann]

Daaaaang!  Just when I start to think my WTM is pushing some horsepower, here you come closing in on 40 FPE with your 135.  What pellets are you using to get 37 fpe, and how accurate are they?  I wonder if these guns are capable of this power in .22, the heaviest .22 hitter I remember anyone posting about so far is still shooting below 30 fpe.  Makes me wonder if 30 fpe is the upper limit for a .22 spring gun, kind of like how .177 springers seem to top out at around 24 FPE...

[Mpac]

Using H&N FTT's 20.06 grain my favorite pellet, it's dieseling a tad still can see thru down the barrel with slight haze very slight.Less than 100 shots in it,everything is OEM in the gun except for a tophat I made out of my 350 mag spring guide just had to shorten the length so it wouldn't collide with the spring guide at the back while cocking.Velocity tar on the spring and moly for the piston.Think I'm going to name this gun BigPoppaPump.

[Bryan Heimann]

Fitting name for such a strong springer.  Even dieseling, that's still a ton of power.  Aside from the extreme detonation, deiseling doesn't seem to give springers that much more power.  You might get an FPE or two.  36 FPE is still crazy power.  With that tophat installed, it ought to increase the weight of the piston enough to shoot a little bit heavier pellet with better results.  I can only imagine that the gun is less hold sensitive with FTT's because they are coming out of the muzzle just as the piston is coming to rest on the air cushion created by the pressure.  I am willing to bet that some JSB Exact Kings, properly flared, will yield better power- but they might make the gun a little more hold sensitive.  I think you should start over with your search for that perfect pellet for power vs. hold sensitivity vs. accuracy, and maybe try experimenting with your hold again as well.  My WTM achieves maximum power with the heavy 36 grain Eun Jin domes, and it achieves good accuracy with them as well, but overall the FTT's shoot the best off-hand as the gun is more forgiving with them than any other ammo.  I can grip and rip and keep them inside an inch at 16 yards (max range in my house) all day.  I know accuracy trumps power, but the FTT's are so light and soft.  It is worth experimenting to find that special purpose pellet for your pest control needs.  Raccoon and down, FTT's- but coyote and up (if you dare try) I'd rock something a little harder and/or heavier.  My favorite ammo is just plain old #3 buckshot, BPI brand.  I can grip and rip and hit my 2.5" spinner every single time- NO misses- at 16 yards.  Grip and rip= off hand, strict follow through but not worrying about the perfect hold.  I just raise it to align my sights and let her rip as the front sight post touches the view of the spinner, holding the rifle tightly enough to maintain my sight picture and sight alignment as good as I can throughout the recoil.  No, I'm not strong enough to maintain the perfect sight picture throughout the shot cycle, but I can keep it on the spinner.  Those buckshot are hard and penetrate really well, and I am willing to bet that they would tear straight through anything fox sized or smaller.  Might result in a ruined gun one day, but in the meantime I am enjoying them.  I should probably experiment with some Kodiaks, and I think you ought to as well.  But anyway, this is all just IMHO...

[Paul68]

More impressive results from ya Mpac.

The 135 with its increased volume certainly should easily surpass 33 fpe in 25 cal. 37 is a bit more than I would have expected, but definitely within the real of reality.

[Mpac]

I would like to stay under 25 grain for the longtivity of my spring since none available till later this year I'm assuming and yes what ever I use I do have to flare if not it's twang city like dry firing I may look at some 23 grain to try out.I owe Fang a bunch of thanks for the springs and the one I have in the gun was tagged 125th spring.I just have to be careful where I shoot this gun the pellets will have some distance at this power level.Thanks Paul68 just love tinkering with power.

[Bryan Heimann]

Here is the lowdown on heavy pellets and spring life- I know you probably know already, but I gotta go there.  The reason heavies are hard on springs, is because the weight and friction keeps the pellet from moving before the piston bounces off the pressurized air.  If the piston doesn't rebound off the pressurized air, the spring is no worse for wear.  I apologize if I am coming off as a know-it-all, I'm not a tuner and I certainly don't know it all.  But when you flare the FTT's, you are creating the same situation as you would be with a heavier pellet- higher pressure before the pellet starts moving.  But that's also why you are getting more power.  That's plenty of power you are getting right there, and I can certainly see why you are happy with the FTT's regarding both the power and the accuracy.  I guess curiosity kills the spring   But you are getting such great results, and we are learning so much from you right now- I just can't help but throw it out there in hopes that you'll do a little experimenting 

[Mpac]

No reason for apology I understand .I did shoot some 28 grain on the hatsan and didn't like the way the gun shot felt sluggish to me by the sound of it shot them around 705 fps and 25 grain at 760 if I remember right.I was looking at PA and see some 22 grain Gamo ProMagnum that I may try a little later after break-in.They will have to be all domed pellets in order for me to flare them.Pa is out of alot of main pellets right now.The spring guide that I'm using for a tophat really has no weight to it but adds more pre-load at it's maximum and had a 350 piston washer in it but mis-calculated my measurement by a 1/8 inch and wouldn't cock,tell me I wasn't mad had to disassemble it again to take the washer out,live and learn.

[Bryan Heimann]

The Gamo Pro Mags are looking good to me, too.  I have also considered giving the PBA's a try.  I know that is sacrilege regarding springers- especially the magnums- but if Chris at C.A.P. is keeping an open mind with them regarding the big .25 bore, then I think I should too.  Besides, I'm already shooting buckshot- might as well push it with the PBA's.  I might learn something.  I am planning to keep it inside 30 yards anyway, perhaps in .25 the PBA are not all that bad.  But, I woiuldn't try them if I weren't willing to risk shattering my piston.

[Ghost]

Could I do the same mods to my 125 and get similar results?
Is there any differences in the powerplant of the 135 vs the 125?

My 125 is .25 also.

[Bryan Heimann]

135 has more swept volume, which is more air pressure and more power.  Without going to extremes with modifications, I doubt you'll get much more than 30 FPE out of the 125.  I do get 33 FPE with the Eun Jin domes, but they are expensive and the trajectory really not worthy.  Plus I have a JM seal in my rifle, and no dampening lubes to speak of.  Just enough white lithium grease on the spring to prevent corrosion and reduce wear on it inside the piston, and just a dab of moly on the piston itself.  no lube = bad news, but less lube = more power

[WHITEFANG]

Mpac<
Been busy but you know how to get in touch with me if you need any of my help. Glad your are slinging the lead. I should have a few more springs if needed.
THE LATHE IS WORKING OUT GREAT.

FANG

[Paul68]

I recently had the pleasure of working on a 125 Sniper in 25 cal. After fixing the usual , and some not so usual issues, with minor modifications and stock spring the rifle produces 33 fpe.

I've found the same trend as Mpac and others regarding the Hatsan 25 cal barrels. They are definitely oversized. Some 25 cal pellets, like Crow Magnums literally FELL over an inch deep into the barrel upon loading. Only the largest pellets seated decently, and even then felt loose compared how I'd normally expect a pellet to seat.

I picked up anywhere from 1 to 3 fpe by flaring the pellets, which tells me the improved sealing is allowing the gun to more efficiently transfer energy to the pellet.

I've also noticed, that out of about 6 differen types of 25 cal pellets, the skirts where substantially thicker than 22 cal. A big part of the sealing depends on the skirt expanding into the bore, and since the powerplant is the same from 177, to 22, to 25 cal, I suspect the thick skirts of the 25 cal pellets are also having an effect on sealing since the pressures are the same, but the thicker skirts dont expand as easily.

At any rate, your posts on the 135 Mpac have only made me more inclined to get one and tinker with it, even though I'm not a fan of the Hatsan lol. I am though a big fan of power from a springer, so if I can fix up issues, its worth it to me;)

[SpringerMan]

The HATSAN 135TH ( Yes, 135, not 125 ) bears some looking at !

http://www.gatewaytoairguns.org/GTA/index.php?topic=43686.new#new

[Mpac]

I recently had the pleasure of working on a 125 Sniper in 25 cal. After fixing the usual , and some not so usual issues, with minor modifications and stock spring the rifle produces 33 fpe.

I've found the same trend as Mpac and others regarding the Hatsan 25 cal barrels. They are definitely oversized. Some 25 cal pellets, like Crow Magnums literally FELL over an inch deep into the barrel upon loading. Only the largest pellets seated decently, and even then felt loose compared how I'd normally expect a pellet to seat.

I picked up anywhere from 1 to 3 fpe by flaring the pellets, which tells me the improved sealing is allowing the gun to more efficiently transfer energy to the pellet.

I've also noticed, that out of about 6 differen types of 25 cal pellets, the skirts where substantially thicker than 22 cal. A big part of the sealing depends on the skirt expanding into the bore, and since the powerplant is the same from 177, to 22, to 25 cal, I suspect the thick skirts of the 25 cal pellets are also having an effect on sealing since the pressures are the same, but the thicker skirts dont expand as easily.

At any rate, your posts on the 135 Mpac have only made me more inclined to get one and tinker with it, even though I'm not a fan of the Hatsan lol. I am though a big fan of power from a springer, so if I can fix up issues, its worth it to me;)

That's why I like the H&N FTT's they are easy to flare or over flare but have the hang of it on how hard to push and with Fang's flaring tool it's a breeze.I know them cans went flying yesterday when hit at 60 yards think I hit the very bottom where the hard aluminum is.Try to shoot 20 or 30 pellets a day to conserve pellet inventory.