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frumious
February 9, 2011, 05:25 PM
Hi I have a Dan Wesson Pistol Pak that was my dad's. I guess it is between 30 and 35 years old. Shoots well, good trigger; I am happy with the gun. It has 4 barrels, from about 7" all the way down to about 2".

Here is how I change the barrel:

1. Unscrew and remove the barrel nut.
2. Remove the barrel shroud.
3. Unscrew and remove the barrel.
4. Screw in the new barrel almost all the way to the cylinder.
5. Right before the breech end of the barrel touches the cylinder, slip the gap gauge in between them. Finger tighten the barrel down against the gauge so that the gauge is sandwiched between the cylinder and the barrel.
6. Now back the barrel out a little, so the gap gauge slides pretty freely. Leave the gap gauge in place.
7. Place the barrel shroud over the barrel.
8. Thread the barrel nut onto the barrel and tighten it down with the supplied tool. Tighten it pretty tight.
9. As you tighten the barrel nut, the barrel itself will also tighten some more. This is why you backed it out a little in step 6.
10. Once the barrel nut is tight, remove the gap gauge. It will not slide as freely but should not be clamped in there too awful tightly.

I sort of figured this out on my own. I have changed the barrels a few times and shot the gun with no issue, but a couple of things bother me. Mainly, how tight does the barrel nut need to be, and how hard should the gap gauge be to remove once the barrel nut is tight? It doesn't seem possible to keep the barrel from tightening that extra bit as I am tightening the barrel nut, so I always have to play with how tight I initially get the barrel so as to keep it from "clamping" the gap gauge really hard.

Right now, in fact, I have just changed the barrel and the gap gauge slid out pretty easily, but I cannot get it back in there. If I hold the gun up to the light, I can clearly see the gap between the cylinder and the barrel. I can see it for every chamber of the cylinder. So I guess it is OK...?

Please advise.

-cls

wogpotter
February 9, 2011, 05:59 PM
I'd say close but no cigar. Not bad for just figuring it out though.
I'd just add:
1: Ensure pistol is unloaded. (I know, I know but you're putting body parts in front of a bore.)

2: Don't back off at all. Once you tighten the barrel firmly hand tight just leave the gap tool in place while finishing up the job. To remove a tight gap tool just open the cylinder. The tool should be removable with a firm tug, but not free enough to slide about or fall out.

Other than that you're good to go.:cool:

This is an excerpt from the factory manual on how to change the barrel & set the gap. The whole manual is available online as a.PDF file at the Dan Wesson website.

Dan Wesson Firearms Revolver Instruction Manual
Small Frame Models
CHANGING BARREL ASSEMBLY
CAUTION: BE SURE REVOLVER IS NOT LOADED BEFORE ATTEMPTING TO CHANGE BARREL.
1. Assemble the barrel wrench to the barrel nut in the muzzle of the barrel.
2. Unscrew and remove the barrel nut.
3. Remove shroud by sliding forward off the barrel.
4. Unscrew the barrel from the frame.
5. Screw new barrel with end containing most thread into the frame
6. Insert .006' feeler gauge against the front of the cylinder and screw barrel into frame until there is a slight pressure against the feeler gauge.
7. Keeping the gauge in place. install new shroud over barrel and locating pin
8. Assemble barrel nut (slots up) using wrench, Tighten so that firm pressure is required to unscrew the nut. DO NOT OVERTIGHTEN.
9. Recheck gap between cylinder and barrel by moving gauge There should be slight pressure against the gauge, but it should be possible to move it.
WARNING: THE BARREL AND CYLINDER GAP IS CRITICAL. FAILURE TO USE THE GAUGE CAN CASUE EXCESSIVE GAS LEAKAGE AND LEAD SPITTING, POSSIBLY CAUSING INJURY
10. Remove feeler gauge.
11. After firing the first six or twelve rounds, recheck for proper gap and barrel nut tightness. Make certain the gun is unloaded for this recheck.
12. If the barrel nut is too tight, making removal difficult, use the fallowing procedure: Be sure revolver is not loaded before attempting to tree barrel nut.
a. With wrench assembled to the barrel nut, press muzzle of the gun and wrench firmly against the edge of a bench and turn revolver counter clockwise.
b. With wrench assembled to the barrel nut, using a mallet, tap back of wrench sharply to loosen nut.

frumious
February 9, 2011, 06:34 PM
Thanks, wogpotter. And yes, I am making sure the gun is unloaded first :D :eek:

Mike Irwin
February 10, 2011, 05:14 PM
See ongoing discussion in The Art of the Revolver.

Please do NOT cross post!