Help bending a Hatsan barrel

[Buk]

I joined the ranks of airgun shooters when I bought a refurbished Hatsan Airtact .177 about a month ago.  Naturally, I wanted to learn more about airguns and in searching the internet found GTA - what a wealth of information is available here!

I started shooting it from my porch at about 45 feet and, after a couple of hundred pellets, it settled down and is shooting well.  My son-in-law - Harvey - expressed an interest in my airgun so my daughter had me order another one as a birthday gift for him.  I checked it out to make sure there weren't going to be any problems with it and I found a problem when I sighted it in.

My rifle sighted in fine with the rear sight maybe 1/8" up.  I later scoped my rifle with a Tasco 4x scope and I had to shim the rear ring and use most of the elevation in the scope to zero it but it shot fine.  Unfortunately, when sighting in Harvey's rifle the rear sight is elevated so high that I wondered if there was enough thread engagement in the elevation screw to keep it in place, and that was sighted in to hit at point-of-aim not a 6-o'clock hold on a target.  Needless to say, I gave Harvey my rifle and now have this one to correct.

Since many refurbs are customer returns and 'changed-my-mind' I'm guessing that maybe it was a return from someone who bent the barrel when they kept pulling on the barrel after it cocked, I don't know.  The barrel seems to be covered with a plastic sleeve of some kind and that brings me to the purpose of this post.

I've read many posts on bending a barrel to correct problems like this and would have no problem fabricating a jig to control the bend but can the barrel be bent with this plastic shroud in place?  If not how do I remove it?  The tube and barrel are out of the stock but before I go any further, can an experienced Hatsan 'mechanic' comment on this?

Thanks in advance,
Duncan

[Roadworthy]

Truth be told I've never even SEEN a Hatsan but in my limited experience barrel droop usually has a cause other than the barrel.  Most common is failure to close completely.  Before starting a bending project put a straight edge next to the barrel to see if it's straight.  It probably is.  Sometimes the breech seal is a bit high preventing total closure.  Sometimes the breech face is not perfectly perpendicular to the barrel - check with a square.  There will be some kind of stop to prevent the barrel from closing too far.  You may be able to file the contact point on your barrel to allow it to close more fully.  If any of these are true you should be able to close the barrel and see if it is not latching fully but is instead angled slightly at the barrel block.  It is possible the barrel is drooping due to an incorrect angle bored into the barrel block but this is not very common.  Good luck.

[mpbby]

Hi Tom. 

Buk is having problem with open sights; the rear sight does not have enough vertical adjustment.

As I presume that both sights are on the barrel, I would like to know your opinion on this.

Marcos

[subscriber]

Tom, not all break barrels have the breech perpendicular to the bore.  Many form a wedge so that the breech face itself limits how far the barrel closes.

Marcos makes a good point about the open sights being attached to the barrel.

I will suggest that Duncan check the stock screws (and sight screws for the front and rear bases) are tight before bending the barrel.  Loose stock (and sight) screws can cause the point of impact to be off, or to drift.  Over tightened or unevenly tightened stock screws can also be a problem.

As for barrel bending advice, finding threads about it are easy via a google search.  For instance: https://www.gatewaytoairguns.org/GTA/index.php?topic=49873.0

Much more via: www.google.com/search?q=site%3Agatewaytoairguns.org+barrel+bending+procedure

[Roadworthy]

My bad entirely, a droopy barrel should not affect shootability with open sights when both are on the barrel.  Whether the barrel closes completely or even at all the sights should adjust.  If it has the original sights and both are on the barrel the first thing to check is probably whether the barrel is in fact straight.  From there bending may be the beat alternative.  I guess I just wasn't thinking.

[mpbby]

I would carefully examine the barrel to make sure that it's not straight, being actually the cause to the open sights trouble. On the other hand, I am not able to suggest how to fix a rear sight itself. 

Btw, besides the open sights trouble in one rifle, you also have trouble when needing to abuse the scope adjustments in the other one.  I don't have any experience with Hatsan or bending a covered barrel.

Have you consider to talk with the seller about the problems?

[subscriber]

Have you consider to talk with the seller about the problems?

A very good question; Marcos


As for the rear sight elevation screw being too short; get a longer one, Duncan. 
Easier than bending a shrouded barrel.

[Xraycer]

After trying multiple, suggested methods which didn't work for me, a hydraulic log splitter got the job done with ease.

[Buk]

Since I only have $50 plus shipping in it, I've decided to keep it as a project airgun.  Maybe I can get my 'fix' working on this rifle and get it out of my system before I buy a more expensive one.  I guess bending the barrel to enable me to lower the rear sight blade is kind-of an extreme solution.  I've decided to make a taller rear sight blade and glue it to the existing sight.  That should allow me to lower the rear sight.

Thanks everyone for your suggestions and comments...........

[subscriber]

Good plan, Duncan

[mpbby]

Buk, you don’t give up easy, and that’s very good; specially for the airgunners. 

Based on my learning curve, besides the excitement to keep shooting, and shooting, different targets and distances, you and Harvey have a lot of things to learn about.  At this point, I will mention some of them.

What is really important is – consistency.  For instance, when you shoot a paper target at a certain distance, smaller the group of holes .. more consistency.  The causes for inconsistency may come from the shooter, rifle, scope, and pellets.

As an air rifle shooter, when intolerable inconsistency happens, you will have to become a well prepared detective to find who is the real guilty among the several possible suspects.  Troubleshooting may be a waste of efforts, time and money when you take the wrong ways. 

Even among the top quality ones, there are pellets that behave more consistently to a - certain rifle, so, you will have to find out which one(s) – your rifle – prefers.  Yes, each rifle has its own preferences.

As long as you keep learning about airgun shooting, you will have to establish, for each distance, what grade of consistency (repeatable group size) is ‘enough’ to your ‘needs’.  When you are intending “perfection” it may jeopardise the .. relax and enjoy.  So, an important decision for each shooter.

I use the term ‘springer’ for the spring-piston air rifles, no matter a steel spring or gas.  A main characteristic of a springer is the 2 recoils.  The first, smaller, happens when you squeeze the trigger and release the piston.  The second one, much stronger, when the piston reaches the end of its course.  The more powerful the rifle, stronger recoils.  The 2 recoils happen in opposite directions, and this is a big challenge for the scopes to keep holding ‘zero’ or even don’t break. 

Btw, as is a natural tendency to scope the powerful air rifles, you should have in mind how the scopes internally work. 

https://life.hawkeoptics.com/riflescope-alignment/

As a highlight, to a scope keep its resistance to repeated recoils, after ‘zeroing’ you have to keep it within its ‘comfort zone’; rule of thumb = maximum adjustments of +- 1 turn for each turret (from the optical center).  You should do a research about ‘centering’ a scope and the ‘mirror method’ for this.

Besides the scope challenge, the 2nd and much stronger recoil of a springer has a critical effect.  It makes the rifle to move while the pellet is still inside the barrel.  And, for any action there is a reaction.  So, for a springer is essential that you find out how is the best way to hold and rest the rifle, in order to minimize, and standardize, the movements; again, you is seeking for - consistency.  For holding springers, some experts adopt the ‘artillery hold’ you may search for.  For resting, always better a soft rest to absorb some forces and minimize the reactions.

The trigger has to be regulated to don’t be ‘hard’.  Each shooter has the own preferences, but the squeezing has to be very easy and smooth, in order you preserve your point of aim (POA).

Once you know how to hold, rest, .., and is comfortable with the trigger, the shooter has to be – consistently repeatable.  Once the rifle is going to move, we should try that the movement is the “same”, round after round.

Another important aspect is corrective maintenance.  A springer has two kind of seals to prevent the compressed air leaking.  Breech seal and piston seal.  Both, and the spring itself, may affect the – consistency.  It would be very useful to have a chronograph (“chrony”) to measure the pellet velocity nearby the muzzle (FPS = feet per second); shooting about 10 rounds, you know the ‘average’ and the ‘extreme spread’ (ES = maximum minus minimum speed); rule of thumb = ES up to 4% of the average, seals are ok).  If the average speed is relevantly below ‘normal’ you should have a spring problem.  When you know the ‘normal’ numbers for your rifle, the chrony acts as a probe to periodically check the health of seals and spring (without disassembling).   

Another effect of the repeated recoils, and as mentioned by Subscriber, is loosen screws.  You may enjoy this..

youtube.com/watch?v=v63d8PsklN0

[Doug Wall]

The first thing that you need to do is sight THROUGH the barrel. That will tell you if it's straight. If you can't see through the barrel, it's bent. If it's bent, then you'll need to figure out how to get the shroud off. I'm not familiar with the Hatsans, so I can't advise on how to do that. If it's bent, you might try calling Hatsan to see if They'll replace it, or tell you how to get the shroud off. Worst case, you cut the shroud off, bend the barrel, and make yourself a new shroud, or figure out how to rebuild the old shroud.

[mpbby]

I don't know if the shroud would be damaged.

I've bent the barrel of my D 350 a few times (no shroud).  As the barrel is flexible, you need a lot of force, and localised in a "point" of the barrel, in order the change rests permanent.  It is a trial and error process; you get where you want by successive approximations.  If you exaggerate, you have to 'undo' a bit, bending to the other direction.

Nced, a GTA member, posted several pictures of his spring compressor device that he also uses for bending barrels.  I did a hole in the wood base of my homemade spring compressor and it became very similar, very useful.

Once you will need a spring compressor to disassemble the rifle - safely, I think you could use the Nced's device as a model.

[gloob]

The Airtact barrel isn't a good candidate for bending.

The plastic shroud is completely hollow. The pencil-barrel is freefloating inside of that, under tension. The muzzle end is threaded, and it's tightened with a nut, hidden inside of the silencer.

If you push out the roll pins holding the cap, you can put a long-reach socket down there to back off the barrel nut. Then the entire barrel can be pushed out the breech end, rotated 180 degrees, and re-installed? Maybe worth a try?

Adjusting the amount of tension might affect the POI enough to help?

If you were really set on it, maybe shortening the front sight and losing the glo-insert?

[SteveP-52]

The Airtact barrel isn't a good candidate for bending.

The plastic shroud is completely hollow. The pencil-barrel is freefloating inside of that, under tension. The muzzle end is threaded, and it's tightened with a nut, hidden inside of the silencer.

If you push out the roll pins holding the cap, you can put a long-reach socket down there to back off the barrel nut. Then the entire barrel can be pushed out the breech end, rotated 180 degrees, and re-installed? Maybe worth a try?

Adjusting the amount of tension might affect the POI enough to help?

If you were really set on it, maybe shortening the front sight and losing the glo-insert?

Maybe if you post the pictures of the one you took apart so he can see what he's up against and he'd get a better idea why trying to bend it
won't be an easy trick.

[gloob]

That was an Alpha, which has the same exact construction. But I already modified it, and it's not coming apart, again!

I never took any pictures of this that I could post in hindsight. Another member has already done that, somewhere. That's probably what you remember!

He did the same thing as me, IIRC. Cut through the barrel with a saw, first. Then in hindsight find out how it was put together. In the old days, the plastic sleeve was solid and just molded over the pencil barrel.

[gloob]

My Alphas needed the rear sight set nearly all the way up, too. I hate that, and I feel OP's pain. At least if a springer shoots too high, you can usually bring the POI down by adding muzzle weight.

[SteveP-52]

Oh I remember it...I wrote it.....
https://www.gatewaytoairguns.org/GTA/index.php?topic=192707.0

[Buk]

Y'all are terrific!  You've taken me, a new airgun shooter, under your wing and really helped with the problem that I had.  Nobody discouraged me from trying to bend it, nobody suggested that I send to to a professional since I didn't know what I was doing, everyone was courteous and helpful - what a great community.  I first wrote about my experiences with my first airgun - the one I gave to Harvey - on the Mississippi Gun Owner's forum (MSGOdotCOM/General Firearms Discussion/"A Tale of Two Targets", June 27) and received great replies there, too.  Just goes to show you the general good character of shooters in general.....