Bent barrel

[Nick D]

I was inspecting some prefabricated parts that are going on to the matchlock I'm building, and noticed something I hadn't noticed before. The barrel is bent just a tiny bit. I checked it with a bar of flatstock, and it's not a swamped barrel, it's a definite bend. It's perhaps 3 millimeters from true.

Now, my thought at first was to put a rod at about the same diameter as the bore down the barrel, then heat a section of the barrel and tap it straight. I figure if I do that I'll have to widen the bore (which I don't really want to do).

Am I definitly going to have to straighten it, or is 2 or 3 millimeters an acceptable margin of error?

 

[Roy]

which way is it bent and does it already have the breech plug installed?

 

[Nick D]

It's basically a barrel blank: no touch hole, breechplug, or anything else.

 

[John Taylor]

I sometimes get barrels in that are bent. I use a press and straiten them without puting anything in the bore. I would not use heat as the bore will be effected.

 

[paulvallandigham]

Why not send it back to the supplier and demand a new barrel that is not bent?

 

[rich pierce]

Just make it so the bend is "up" not side to side, and don't worry about it much.

 

[mikelange]

If sending it back to the supplier isn't an option, for whatever reason, I second what Rich said. Install the breechplug into the barrel and the barrel into the stock so the bend is up -- in other words, so the gun shoots somewhat high. If you're using a front sight, install one that's a bit on the high side, which in straight barrels has a tendency to make them shoot a tad low. It ought to balance out.

If you're building a musket with no sights, odds are you'll be shooting at fairly close range and tending to hold low on whatever you're aiming (pointing) at, in which case the flaw in the barrel won't have any practical effect.

FWIW, my first deer rifle was a Remington 700 ADL, .243 Winchester. Turned out it had a very slightly bent-down barrel. My dad and I fiddled with the scope to compensate, and the gun was a tackdriver at 100 yards.

 

[robinghewitt]

Just make it so the bend is "up" not side to side, and don't worry about it much.

That sounds perfectly PC to me :thumbsup:

My matchlock barrel is bent and someone, in the last 360 years or so, fixed it by cutting back the rear sight to cant the gun so it shoots high rather than off to one side :grin:

 

[Nick D]

Thanks all, I think I'll just install the barrel "bend up".

Here's a pic of the barrel in question:

 

[John Taylor]

looks strait enough to me.

 

[bavarialand]

Navy? ship and station?... Me, USS Ranger CV-61 1984-88, SanDiego. Dave

 

[Nick D]

'Fraid not :redface: The hat was a gift from my Dad, who works on building ships and hardware for the Navy. It's become my shop hat after years of wear (and tear).

 

[bavarialand]

thanks, Dave

 

[John Taylor]

I was on CVA 61 for a few weeks in 71. On CVA 63 in 69. My brother was on CVA 61 in 67. I saw it sitting in Bremerton about 8 months ago.

 

[Zonie]

How the H did we get on board a bunch of Navy Ships? I thought the subject was a bent barrel.

I also didn't know until now that CVA even existed in 1961. :rotf:

As for the bent barrel, it can be rebent without structurally damageing the material.
To allow for springback, you will have to overbend it a little beyond the 3mm bend it currently has.
If you know which way it's bent and about how much, support the ends about 1/4 inch (6.3mm) off of the floor with the bend up. Stomp in the middle using all your weight to bend it down until it hits the floor.
(The 1/4 inch is a guess. If you don't feel daring, you may want to start with 1/8 inch blocks).

Recheck the straightness and adjust the height of the supporting blocks if required. My guess at 1/4 inch may not be enough to remove a .118 bend.

When you get tired of stomping on it, do as the others suggested and intall the barrel with the low part of the bow down into the stock (ends high so it shoots high).