swamped barrels

[flaming canvas]

Are they more susceptible to swelling in the stock than straight octagons? I haven't had mine for a year yet so I'm still learning how the rifle shoots, but it seems that the POI is shifting vertically on me.

 

[mazo kid]

Swelling in the stock?? Don't mean to belittle your question, but steel doesn't swell much. Make sure your barrel pins/keys have a bit of slack in the holes so the barrel heating up doesn't bind against them and cause the barrel to move POI.

 

[fw707]

Are they more susceptible to swelling in the stock than straight octagons? I haven't had mine for a year yet so I'm still learning how the rifle shoots, but it seems that the POI is shifting vertically on me.

I have 3 guns with swamped barrels and I've never had a problem with any of them.

 

[Zonie]

Because a swamped barrel tapers outward on both ends from the middle, theoretically the barrel is locked into the wood but in real life, the taper is very slight and the clearance between the barrel and the wood should allow it to expand and contract freely.

I would do as mazo kid suggested and look at the holes thru the underlugs on the barrel.

These holes should be elongated with the vertical dimension the same as the barrel pin and the horizontal dimension (in the direction of the barrel) elongated at least 1/16 more than the pin diameter. A elongation of 1/8 of an inch is even better. This allows the pins to move in the direction of the barrel as the barrel heats and cools and more importantly when the wood shrinks or grows due to humidity.

If your underlug holes are just round holes you can elongate them with the use of some needle files.

 

[rafterob]

As new barrels get "shot in" the POI may change somewhat. After a 100 or so shots it should have settled in.

 

[flaming canvas]

I will try elongating the holes for the pins. We have a lot of variation in humidity here. When I finished the gun last spring we were well into a period of low humidity, around 10%.
In August I was changing the rear sight and the barrel wouldn't come out of the stock because of the swelling. At the same time the patchbox got hard to open and the wood around the tang was standing proud so I know there has been some change in the wood. It has been dryer now for a month and things are going back to normal. The patchbox is loose again.

 

Hey Roger,

Before I moved out of NM, I had an O/R barrel that Dave Rase in humid Washington inlet for me into a sugar maple blank. It was perfectly inlet when I got it over the winter. When the monsoon season hit, that sucker swelled up and stuck in there until I couldn't budge it out of the stock for months. It finally came lose a month after we moved out onto the plains. I feel your pain. In the SW, its not about the average weather. Its about the variation. Its like the guy who was talking with the tourist down at Oliver Lee State Park. The tourist asked him how much rain they got in a year. He told her about 7". She said, "Well that certainly isn't very much." He replied, "You shoulda been here on the day it fell."

Sean