Barrel droop on Webley Longbow

[Palverizer]

Ok,
Not shot this for long time,
Came to Mount a scope and zero,
Ran out of clicks on elevation turret and after further investigation discovered barrel drooping !
Now I've shimed Mount to compensate and it's still shooting ok but ".
If i want to correct this barrel droop ,
What are my options ?
And why has it occurred ?
Not a particularly old gun ,perhaps 10years with little use really '.

 

[Deejayuu]

Has the barrel shifted in the block. Look for a gap between stepped diameter and block. Only glued in
Installed a grub screw on underside of ours.

 

[Ashf9999]

If the reason is because the barrel has snapped shut under spring load, it’s best straightened. They’re not likely to move of their own accord. Remove the barrel from the gun but don’t strip it from the breech block. A sturdy bench vice (with soft jaws), some cloth to wrap round and protect the barrel, and a suitably stout long tube over the end of the barrel are what you need. Secure the breech block into the vice and gently lever the tube in the appropriate direction. Stop and check frequently. A straight edge (metre rule or kitchen worktop) will let you check the straightness before reassembly, as will putting the muzzle to a light and looking up the bore.

 

[norseman]

If the reason is because the barrel has snapped shut under spring load, it’s best straightened. They’re not likely to move of their own accord. Remove the barrel from the gun but don’t strip it from the breech block. A sturdy bench vice (with soft jaws), some cloth to wrap round and protect the barrel, and a suitably stout long tube over the end of the barrel are what you need. Secure the breech block into the vice and gently lever the tube in the appropriate direction. Stop and check frequently. A straight edge (metre rule or kitchen worktop) will let you check the straightness before reassembly, as will putting the muzzle to a light and looking up the bore.

No offence but will such a method really correctly straighten a barrel?
An error of a thousand-of-an-inch will be magnified when shooting at any distance.

 

[Ashf9999]

No offence but will such a method really correctly straighten a barrel?
An error of a thousand-of-an-inch will be magnified when shooting at any distance.

Yes it does. Barrels often have ‘memory’ in that they will go back to straight with a little encouragement. Though traditional barrel straighteners were press contraptions that can be used to apply pressure at different points along the length, the effect of a vice, if done carefully, is the same. If you have access to a lathe you can check for runout, though studies have shown that providing the last section at the muzzle is pointing the right direction then in theory the rest is less important.

 

[P8X]

Ok,
Not shot this for long time,
Came to Mount a scope and zero,
Ran out of clicks on elevation turret and after further investigation discovered barrel drooping !
Now I've shimed Mount to compensate and it's still shooting ok but ".
If i want to correct this barrel droop ,
What are my options ?
And why has it occurred ?
Not a particularly old gun ,perhaps 10years with little use really '.

I'd say the Longbow barrel is unlikely to display barrel droop. Droop is more related to how barrels are fixed in the breech and really only related to Diana's, though the term is misused on other rifles and brands. Most others will just be bent.

Look at the barrel, where it enters the breech
Is there a pinch and a gap? Where are these, top or bottom?
You have to identify where the barrel could be bent.
Look down the bore, breech to muzzle. Can you see a clean central bore or is there a shadow?
If by misuse, letting go on cocking, they generally bend upwards.
A downward pointing barrel generally occurs by accident, like dropping. I'd also explore whether it has any lateral bend (side to side)

All barrels can be straightened
Identifying how they're bent and which way, will enable folk to give proper advice as to how they should be straightened

 

[P8X]

The Longbow having a shortish 13" LW barrel should resist bending pretty well, by either an accidental release on cocking, or an impact
I'd anticipate the barrel will just have bent, right where it enters the breech, the remainder being quite straight

Longer barrels are more prone, to have some sort of graduated curve, especially if let go when cocking, but again all rectifiable

One mk1 85 I was asked to look at had been let go on cocking and the lady dropped in in shock, when it happened. That hit the floor and was also bent laterally. Even that was easily straightened. The twisted raised scope rail was another matter entirely, as a result of the scope hitting the deck, when it was dropped

 

[Palverizer]

Thanks for all replies,
Very helpful and informative.
On a quick inspection of barrel shut the it doesn't appear to be a bent barrel ,
Rather dipping from pivot point at breach.
As mentioned by a previous poster,
When shut the margin along top of Breach doesn't look even along line of seating.
I will take stock off and get some pics,

 

[P8X]

Thanks for all replies,
Very helpful and informative.
On a quick inspection of barrel shut the it doesn't appear to be a bent barrel ,
Rather dipping from pivot point at breach.
As mentioned by a previous poster,
When shut the margin along top of Breach doesn't look even along line of seating.
I will take stock off and get some pics,

That could be other external factors then
I'd be looking for any damage around the mating faces of breech and cylinder plug
Look to see whether something simple like an incorrect breech seal has been used, preventing lockup
Whether the cocking arm is bent in any way, preventing lockup

I also had one Brummie Longbow on which the breech detente chisel was very stiff and sticky, causing lockup problems. To check this out, remove the barrel and press the detente chisel on a block of wood and compress it, to see if it moves freely. If it doesn't, it may need removing, cleaning up and relubing. It was a quick resolve on mine

 

[Palverizer]

Cheers for that,
Will do first opportunity.

 

[Palverizer]

Ok,
I have added a couple of pics, the breach closes nice and tight at top so can't see an issue their.
I did remove barrel as suggested and found a tiny bur on latch so filed it clean,
Everything else seems ok, breach seal fits slightly proud but is not obstructing from closing tightly.
Reassembled and just same as before,
Im now thinking it has been bent from point where barrel connect to breach block.

 

[chouchin66]

Ok,
I have added a couple of pics, the breach closes nice and tight at top so can't see an issue their.
I did remove barrel as suggested and found a tiny bur on latch so filed it clean,
Everything else seems ok, breach seal fits slightly proud but is not obstructing from closing tightly.
Reassembled and just same as before,
Im now thinking it has been bent from point where barrel connect to breach block.

Remove barrel, lay it on your bench & check clearances @ breech interface & muzzle end using identical stacked washers, feeler gauges & a straightedge...that'll tell the tale.