Discussion in 'Gunsmithing' started by nobu, Nov 14, 2016.
I think I know what back boring is but is that related in any way to forcing cones?
A forcing cone is the area of transition between the chamber of the barrel and the bore. It is also the area of transition between the bore and the choke. Both are technically forcing cones
Back Boring is the opening of the barrels original ID which also affects choke performance.
Lengthen forcing cones have nothing to do with felt recoil if that's what you're looking for.
Thanks for the replies. I never mentioned felt recoil but that is exactly what I was aiming for because I was told that both back boring and/or lengthening the forcing cones was a way of reducing felt recoil. I'm going to post another subject about my recoil persuit. Thanks.
When you change the specifications of the barrel you will affect the felt recoil. HMB
The concept of lengthened forcing cones was to reduce shot deformation as the shot was transferred from the hull to the bore. That's it
I disagree smokintom,
Removing and lengthening the forcing cones does reduce felt recoil. You are correct stating the original
concept of lengthened forcing was to reduce pellet deformation but the forcing cone alteration also reduces felt recoil.
The biggest reduction of recoil comes from increasing the inside diameter of the barrel through back-boring.
But Eddie ? Wouldn't that be Over-Boring a barrel as Back Boring is when , just the area of where a choke tube is , is swedged-out to a larger diameter ?
3200-man-2, But Eddie ? Wouldn't that be Over-Boring a barrel as Back Boring is when , just the area of where a choke tube is , is swedged-out to a larger diameter ?
I've had three OU's, an auto and a SXS ( with dedicated chokes) back bored and their choke areas were never touched .
Can you explain what advantage or benefit that altering the choke tube area would produce?
Opening just the area behind the choke for a few inches is normally called jug choking. Backboring without touching the choke area would increase the constriction of the choke by the amount of the backbore unless tapered backboring is used. I don't know if anyone is still doing that. Overboring is what manufacturers did to sell some sizzle on their new guns when backboring was the cure all for patterning, reducing recoil and various other claims. This resulted in the overall diameter of the barrels being larger and increasing the weight of the barrel sets as compared to that manufacturers pre-overbored barrels. Just compare a set of American Browning 325 32" barrels to the European non-overbored 32" barrels. I had a set of pre-overbored 32" barrels backbored .020" and they were lighter than the 28" overbored barrel set.
Smokintom has no idea...
I agree with Eddie.... backboreing DOES reduce felt recoil......as most recoil
occutes when the shot first leaves the hull.
So your saying take two identical guns. One with a standard forcing cone and one with a lengthened forcing cone firing identical shells that the one with the long forcing cone will kick less ??? Come to Ohio there`s a bridge down the road I would like to sell you.
When you back bore a barrel or when you lengthen the forcing cone of a barrel you remove metal from the barrel.
When you remove metal from the barrel you reduce the weight of the gun. When you lower the weight of a gun
the recoil increases. You can't argue with recoil science. HMB
Newton's rules apply to everything but shotguns.
Were Newton's barrels back bored? HMB
Find a copy of Barrel modifications by Tom Roster that should answer your Questions.
Lol! HMB, that was a good one. Thanks for the laugh!
Newton only owned rifles. I don't think he back bored them.
If Over-sizing the bore of a shotgun wasn't beneficial , why are most all manufactures offering over standard bored barrels ? I read where Newton loves them ......
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