R1/Hw80 pivot bolt adjustment.

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Mycapt65

Member
Apr 24, 2019
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NY, United States
Any one else find their R1 or Hw80 needs a fairly snug pivot bolt adjustment?
I'm getting vertical stringing if the pivot bolt isn't somewhat on the tight side. It seems the recoil or start pressure pushes the barrel down a touch. With a standard pivot adjustment where the barrel just barely holds itself in position when cocked, the gun looses ten fps and POI drops considerably. If I snug the pivot so there's some noticeable drag while closing the barrel the POI remains high and steady. The extra drag is still smooth but it just feels weird to me.
I'm wondering if these guns typically need tighter pivot adjustments than the lower power models.
Thanks
Ron
 
vertical stringing is a velocity issue ..


I’d pull barrel off and inspect the chisel spring and detent .. a springer should not loose any velocity when snugging the forks.. As stated it sounds like a bad breech seal. Test it with super thin toilet paper held over cocked breech with tape or talcum powder ,but it’s messy. I can tell a leaking breech by feel and ear.. chronograph will tell velocity drop

break barrels should not swing freely. They should hold them selves up with a little resistance when pushed
Make sure you have the split washers on the bolts to hold adjustment Tension
 
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Hey Bayman,
I'd take out the indent and spring to polish/lube, check breach seal to make it's not proud.
If you still see the stringing, tighten pivot bolt as you've done.
I like my pivot bolts a tad tight - no barrel swing at all. Probably a little tighter than "where the barrel just holds itself."

Could be slight beach misalignment, but I'd just tighten the pivot bolt and forget it:).
 
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This has happened with four different barrels three of them new. I've removed and polished the detent spring ends and bores on all of them the small velocity loss (ten fps) only happens when the pivot bolt is looser. With a looser pivot bolt the POI drops. The barrel is dipping on the shot and burping a tiny bit of air.
Snug the pivot bolt and it basically goes away. At least until I but I try to up the power. The tip of the fixed detent I a little worn but there's no play in the lock up.

I'm wondering if this has more to do with the having the longer barrel and harsh recoil.
 
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Was this a factory gun or someone’s tuned work? Many will try to take a coil off to get a easy to break barrel. This is a bad idea as that same spring holds it shut. A leak is what you have at the breech seal caused by poor detent lock up
It has to come apart. Check spring and degrease and clean well. If it’s worn you will need new spring. The detent can be polished but do not remove any material.
It’s is why they are called break barrels.
 
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That's a lockup issue.

The barrel should stay sufficiently locked up even without any tension from the pivot bolt. It's there to take up lateral slack, and really nothing more.

If this is a gun made after say, 2012ish, it has the bolt on detent wedge on the receiver. Make sure it's not loose, moving, or has any weird or irregular wear patterns. If youve tried other barrels then it seems likely that the receiver is the issue.

If it's an older receiver, and you're using new production barrels, there could be some tolerance difference there and cause your issue.
 
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