Barrel bore very off center.(Updated new barrel issues)

[redlined_b16a]

Like I stated the off center is of no concern anymore.When I first noticed it I had never heard of this issue.
I have email Hatsan and filled out a form plus sent a picture but on the customer service form it ask specifically if I tried to repair it myself.
I was honest so I already know im on my own and thier reply will be that they can sell me a replacement barrel.

[Gerard]

True enough. It it ain't broke, don't fix it. Problem is, the guy's gun isn't shooting well at all. Big groups, off to one side so he has to shim his scope. Not good. Sounds to me like that disturbance in thee rifling might be the worst of it. Time to chop and crown.

[Ribbonstone]

That ding on the land is a problem.   Not something I'd want to fix unless I had no other choice. (it's a PIA to cure).  Best would be a new barrel if possible.


But if it were a barrel I couldn't replaced, would counter sink the barrel...likely bored back to a 3/8" hole  just past the land-ding, then crown the deeply recessed crown.  That way, you get to keep the outside (and threads) just as they are...cutting the barrel and recorwning will lose at least part of the threads.

[redlined_b16a]

I was going to ask that question next on the counter sinking,If tgat has been done.Ofcorse Id let a machine shop do that.

Probly cheaper to buy a barrel from Hatsan.

That ding on the land is a problem.   Not something I'd want to fix unless I had no other choice. (it's a PIA to cure).  Best would be a new barrel if possible.


But if it were a barrel I couldn't replaced, would counter sink the barrel...likely bored back to a 3/8" hole  just past the land-ding, then crown the deeply recessed crown.  That way, you get to keep the outside (and threads) just as they are...cutting the barrel and recorwning will lose at least part of the threads.

[redlined_b16a]

Options on repair
1: Counter bore as suggested but If I do that it would be a professional machine shop and how would I crown a counter bore.

2:machine off the damaged portion and re crown,make a new shroud retaining nut longer to reach all of whats left of the threads.I did not measure but that damaged land is about 5/16" into the barrel.

3: cut and machine just run shroudless and use a standard LDC which worries me cause its detachable and may cause legal problems.
Bull Boss is very loud shroudless

4: Buy a new barrel

[Dan H]

new barrel 

[Vee3]

This was supposedly still accurate after the "mod" they did, lol...



"After one of the big SHOT trade shows, the owners of the Westinger & Altenburger Co. (Feinwerkbau) of Germany presented us with this amazing feat of airgunsmithing - a Beeman/Feinwerkbau Model 2 CO2 pistol with the barrel making a complete twist around the gas cylinder! The gun actually shoots quite well! Note that the all-important final inch(25 mm) or so is straight - that and the crown are the only really important parts of the barrel as far as accuracy is concerned. When some shooter would say " I think I see some little defect in the rifling way down inside my barrel, or the middle is a little off, or the barrel is not quite straight, and that is why I am not shooting well" , the airgunsmiths loved to bring out this gun and ask if his gun was more off line than this one!"

[Rocker1]

 I see a lot of guns like that have had to eat several ldcs because the barrel  bore is off center especially qbs and hatsans, hatsans worst is the threads are crooked on the barrel.  David

[Wayne52]

I see a lot of guns like that have had to eat several ldcs because the barrel  bore is off center especially qbs and hatsans, hatsans worst is the threads are crooked on the barrel.  David

David on the LDC's that I've gotten from you there's plenty room in them to work just great as long as they're not real crooked, I haven't had any crooked threads that I can tell on any of my SPA guns.

[redlined_b16a]

Hatsans reply


Micky,

We are sorry to hear that you are having issues with your Bullboss.

Your RMA number is xxxxxxxxxxxxx.

Please send it to the address below, along with copy of your receipt and
a copy of this email.  We will repair your item.  If it's determined that other
issues were caused by something other than manufacture's defect, i.e.
user error, tampering, abuse, etc., we'll contact you with a cost of the
repair and return shipping before we do any work.

For Pre-Charged Pneumatic (PCP) guns, we WILL NOT process your
repair unless the air cylinder and at least 1 magazine are included.


I asked if I could send just the barrel.
I have a feeling it is not worth sending since I recrowned it.

[nervoustrigger]

Yeah based on the statement about PCPs must include the air cylinder and magazine, there’s nearly zero percent probability they would accept the barrel only.  From their point of view, I can totally understand that.  The visible rifling defect is perhaps the only thing that would justify sending just the barrel so make your case (or reiterate it) along with the photo and see if they will accommodate you. 

[redlined_b16a]

I don't expect them too just take the barrel but worth a shot.
If they decline just taking the barrel for inspection I'll move to plan B.
Try to use needle files and get rid of that dent.Check for group Improvement.

Plan C.
Try to counter bore barrel

Plan D.
Look into machining off the damage and making an extended shroud nut to catch threads futher back.

Plan E. Buy a replacement barrel

I just dont want to waste money mailing a gun for Hatsan to Say the gun has been altered and your repair cost will be $$$.

[redlined_b16a]

I pushed a Jsb 33 grain through the barrel and the pellet is tight all the way through the barrel and its tight all the way through.

The pellet did catch on that damaged spot.
So I followed through with plan B.
Carefully filled down the ridges.Pudshed a pellet and cleaning patches.No more catching.Took several attempts.I will group Tommorow to test results.

I looked at the shroud nut and only half of the threads hold on.
If I make barrel shorter to machine out the bad spot I will have to trim the shroud on the muzzle end to make it work but I think its do able.

[redlined_b16a]

Good news from Hatsan via email.
They reviewed my photos and after I asked I can send just tge barrel and they will send me another one.

[nervoustrigger]

That’s great, glad to hear they are willing to work with you.  Most places would rigidly stick to the written policy of sending the whole rifle back. 

[redlined_b16a]

I sent another email asking specificlly that since I re crowned and tried to file out that dent if they will charge me for a barrel.

Hatsan said no they will not  because I tried to correct the issue.

Thats pretty cool

[Verminstalker]

The bullboss measures .024" off center.
My 3 jaw or my ablities do not allow me to compensate that much accurately.
Next step is to buy a 4 jaw or get an outside machinists involved.

I know you have the barrel being taken care of by Hatsan but one suggestion on crowning an off center bore the next time would be a hand turned crown cutter with brass pilots. It centers in the bore so regardless of the outer barrel shape, the tool is squared in the bore. I've used this tool on many centerfire rifle barrels when I was working as a gunsmith. Polished the crown with a brass crowning tool and fine compound.

[redlined_b16a]

Hatsan USA is finally mailing me a new barrel.
Was just about to give up.

[redlined_b16a]

New barrel arrived.Crown looks nice.
Transfer port shaves pellets.....easy fix but 6" from muzzle end tgere is a larger i.d. spot the the pellet gets loose in and it catches when pushed through.
None the less I will see how it groups.
It was the dirtiest barrel I had ever seen.
The black dirty ring is where the i.d. is larger and patches can not clean there.

[redlined_b16a]

Excellence is upon me so far.
Benji 27grain  and jsb 25 grain hole in hole at 35 yards

The crappy 33grain jsb first gens about a 3/4" group

Happy so far