Barrel Change Old Model Blackhawk

[Pete]

I just removed a pitted barrel from an Old Model .357 in order to replace it with a take-off barrel I bought.The removed barrel screws in by hand but the replacement barrel will only screw in to the frame one full turn.Both barrels are .680 in. diameter on the threaded shank and have 24 T.P.I. Any suggestions on what else to check to see what is binding?

 

[rugerguy]

if you cannot "see" anything binding ,such as a burr or cross cut thread,,,then my guess is the thread pitch is OFF ,NOT the same.........check with a gage..............

 

[Pete]

Thank you,I will check again.

 

[Hondo44]

Chck the threads on the replacement barrel for a tiny ding in the threads. All barrels should interchange.

Is the replacement barrel an OM? But NM barrels should work.

Clean threads well in frame and on barrel with bore cleaner and barrel brush. Use a good lubricant like Breakfree. Sometimes you have to use whatever you grabbed the old barrel with to turn it in. As long as you don't have to force it in, it'll be fine. Snug is good.

Let us know how it tightens up; is front sight straight up and down, too far to right or left, etc.

 

[Pete]

Thank you much! It is an Old Model barrel.Soon as I can get to my tools I will check the thread pitch but I thought all the mid frame Ruger single action .357's had the same thread dimensions.The thing that bothers me is i have two other pitted barrels and both will turn into the frame but this one hangs.I will try tomorrow to clean again and lube it and see what happens.I really appreciate all the suggestions!

 

[Pete]

Another question,would it be beneficial to use an 11/16 - 24 re-threading die on the threads?

 

[jringo8769]

well i ran into this myself...i found out the barrel i had had at one time had a squib round and my gunsmith and myself measured the barrels and found out it was just a little larger at the threaded area...i am hoping u do not have that problem...i was going to rebore my barrel so it did not matter...but i would check as it is very easy to see...God Bless,John
our was very hard to tell without some tools to measure it

 

[Muley Gil]

I had Alan Harton down in Houston convert a OM Ruger Blackhawk .357 to .44 Special using a Super Blackhawk barrel. Alan also converted another OM .357 to .44 Special using a Colt New Frontier barrel.

 

[Hondo44]

Another question,would it be beneficial to use an 11/16 - 24 re-threading die on the threads?

Pete,

I would not run a tap thru the threads if they're not cross threaded or otherwise damaged. They take out too much metal resulting is loose threads. I'd use a thread chaser instead, if needed.

You're correct all mid size frame barrels and most large frame barrels (old and new models) use the same thread pitch and size with very few exceptions which are:

SBH Hunter barrels are the exceptions; thread pitch and diameter varies:

.41 SBH Hunter is 32 TPI x .708" (shank diameter is .623"),
44 SBH Hunter is 20 TPI x .747" (shank diameter is .680"), (same as Super Redhawk)
.45 SBH Hunter is 32 TPI x .703" (shank diameter is .623").

 

[Pete]

Thank you all for the help! I should have posted this earlier but both me and my wife have been sick.I got the barrel on and correctly timed,It was a little tight to begin with but finally with a little patience I got it fit to the frame.I have shot it several times since then and the only problem is the front sight is just a little short.Now I have to figure a way to add about 0.09 inches of height to the sight blade.

 

[Hondo44]

Bravo!

Were the two barrels the same length? 0.090" is a big difference, almost 1/10". The neatest way so you don't have to do any soldering and rebluing the barrel is to call Ruger CS (336) 949-5200 to get just a new front blade w/o the base WITH A CROSS PIN, and ask for the tallest they make like for the .45 Colt (.440" high). They'll send any parts less than $20 for free and one blade is about $8. They are for stainless guns which have a stainless sight base and a blue blade pinned in a milled slot.

You can cut the blade off, neatly level the surface, cut a 1/2 moon slot if you have a little skill with a Dremel tool using a carborundum cut off wheel. Make it snug so you a slight "interference" or "press" fit and drive the blade in with a brass punch. That may be all you have to do, or clamp sight in the groove, drill thru and install pin. Or have the slot milled locally.

Or ask for the whole sight base with blade $9 so it's also free, and also a singles six front sight screw. Cut and grind off the old sight being very neat when you get down close to the barrel bluing using tape. Drill and tap the barrel, and drill and countersink the sight (like on the Single sixes) and screw sight on. Ruger's front sights are silver brazed on and take so much heat to remove, the bluing is ruined on the front half of the barrel.

Any questions just ask,
Jim

 

[Pete]

Jim, Thank you very much for the help and information.The suggestions and help I have received from everyone is much appreciated! I calculated the height addition from at the groups I fired at the range and am confident on the increase.I have a sight coming from Two Dogs and hopefully can find someone close to silver solder it on the barrel.Once I get the sight set and the barrel re-blued I will report back how things went.
I wish I could cut the blade down and cut a slot with my Dremel but at my age things are a little shaky and I would hate to ruin something.

 

[Hondo44]

It you wanted to try using your Dremel tool just for fun, you have nothing to lose since you'll be removing the sight base any way.

Just FYI:
The trick, is to clamp the Dremel tool horizontally in a vise and use it like a bench grinder. And hold the gun. Because the gun is so heavy, it's much easier to hold it steady than the rotating Dremel tool.