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Barrel Breech Leade Taper Rate

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Motorhead:
AKA:  Throat loaded where a probe pushes pellet to the far side of transfer hole, Typically a leade or free bore is made.  This free bore is basically at the pellets head diameter or a tad larger.
When pellets head passes transfer hole it is in the rifling and as skirt passes transfer hole and seated no further it is resting on transition of free bore to rifling. 
A blended in or sight ramp of rifling is best as it presses into pellet not cutting it.

Took most of the day ... Lol, hope this helps  ;)

Ronno6:
Mr. Scott,
I last edited my post after your reply, which I had not seen at the time.

I think I will lightly touch the bore at the breech using a Dremel and a stone while the barrel is turning in the lathe....
The OEM barrel breach sees the pellet skirt drop in about .125" past the opening when inserted into the breach.......

OK. I think I have learned the nomenclature.
First, the pellet passes thru the freebore/throat, which is straight and un-rifled.
It eventually enters the bore. which is fully rifled.
The leade is the tapered transition between the other 2 sections........now I MIGHT not sound like a complete idiot......

I have seen the leade taper listed at 1.5deg, but not specified as per side or total......

Psipumper:

--- Quote from: Ronno6 on September 29, 2024, 05:27:40 PM ---
--- Quote from: Motorhead on September 29, 2024, 02:51:03 PM ---Not familiar ... how does the pellet load, is there a transfer port and a probe seating pellet deeper than flush ?

--- End quote ---
The pellet loads into the breech of the valve body.
The transfer port is in the valve body, not the barrel.
The barrel buts up into the valve body maybe .060" beyond the TP
The bolt probe should about push the pellet skirt at or just past the edge of the TP....
Does this mean that the barrel does not need  any taper??
That would be great!

The 362 barrel does have a TP, hence the lead taper??
That will be removed for use in the 822........

Update:
I have half of an 22X barrel that must have come from a police auction...it was cut in 2.....
A pellet dropped into the breech end drops freely so that the end of the skirt is maybe 1/8" past flush.
The pellet drops into the loading end of the bore of the 362 barrel about the same,
but when dropped into the muzzle end, the skirt comes flush with the muzzle....

So...........back to the original question, I suppose..........

Maybe just a gentle grind with a Dremel while in the lathe??

--- End quote ---
If the barrel is.060 past the transfer port , it should only need to be faced off square and add the smallest of deburr and polish so not to shave the pellet.
The caliber is 5.5 mm (.216”) if one needed to drill the chamber.
I haven’t gotten technical enough on the lead angle and have just polished whatever angle is on the end of reamer or drill.

Motorhead:
1.5* would be a per side.

Tho jus at smoothed up Non abrupt entering onto rifling is all your looking for.

Ronno6:
I was only looking for the angle to see if there was a taper pin reamer that would do the job.
But, they are way too expensive.........
So, I am going to prescribe to the old "If it looks right, it must be right" philosophy.

Thanks. y'all !!

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