Barrel cylinder alignment

Kevin Stenberg

Well-Known Member
I didn't want to step on Brads thread. So i started this one.
When inspecting a revolver before purchase. #1 = Is there any way to check a revolver for cylinder alignment with the barrel when it is locked with the hammer cocked? #2 other than having a pin gauge with you. Is there a way to check the cylinder throat dia. when inspecting the revolver?
 

Ian

Notorious member
Mk I eyeball and a very bright LED pen light. Calibrate eyeball beforehand by practicing reading the light rings in your own revolvers at home. Shine light between cylinder and recoil shield to illuminate the recoil shield as you look down the muzzle. Line up the muzzle ring with the forcing cone ring and see if that lines up with the ring at the back of the chamber in the cylinder. Might have to move your head around a little (orbit) to see the edge of the chamber if the barrel is long and cylinder short, but you can get the hang of determining the concentricity of the three rings if you practice.

Carry some different sized bullets in your pocket. Scribe the size on the base with a pocket knife tip or nail. Use them for test fitting. Even having one of the size you prefer to shoot, or shoots well in your other guns of the same caliber, would be useful for determining how far over or under the prospect is in comparison.
 

358156 hp

At large, whereabouts unknown.
This method may not work with Colt revolvers. Colts have a 2 stage hand (pawl, whatever) that don't align the cylinder to the barrel, or even lock up fully until the trigger is fully depressed to the release point.
 

Jeff H

NW Ohio
This method may not work with Colt revolvers. Colts have a 2 stage hand (pawl, whatever) that don't align the cylinder to the barrel, or even lock up fully until the trigger is fully depressed to the release point.

I do what Ian said and then let the hammer down while holding the trigger back before looking down the bore - still holding the trigger back. It can be awkward and you will get some funny looks, but it works. Practice at home makes a big difference with recognizing what you're looking at, where/how to shine the light and how to more gracefully pull this off.

I would add that when looking down smaller bores and/or longer barrels, you have to consider practicing your best Popeye face to get anywhere. It's the hardest part to master but easiest to practice, because you don't have to have the gun or the flashlight to practice. You can even do while driving to/from work, but just not at stop lights. ;)
 

Paul Gauthier

Active Member
There are gages available for someone, I wish I could remember who. But they can also be made. They fit snugly in the barrel and slide into the cylinder if alignment is correct. I would check Brownells first.
 

358156 hp

At large, whereabouts unknown.
I do what Ian said and then let the hammer down while holding the trigger back before looking down the bore - still holding the trigger back. It can be awkward and you will get some funny looks, but it works. Practice at home makes a big difference with recognizing what you're looking at, where/how to shine the light and how to more gracefully pull this off.

I would add that when looking down smaller bores and/or longer barrels, you have to consider practicing your best Popeye face to get anywhere. It's the hardest part to master but easiest to practice, because you don't have to have the gun or the flashlight to practice. You can even do while driving to/from work, but just not at stop lights. ;)

This is pretty much the only viable option for a Colt, and this is the method I use. My only concern is trying to look down the barrel and manipulate the trigger & hammer simultaneously without pushing the trigger all the way back until it stops. Most Colt triggers don't have a lot of post-release travel anyway. Not like some Smiths & Rugers I've seen.
 

Charles Graff

Moderator Emeritus
Years ago, Elmer Keith wrote about checking the alignment by cocking the hammer and looking down the barrel at the light coming through the firing pin hole. With a little practice at looking at the light, it is pretty easy to spot a chamber that is not dead straight with the bore.
 

Pistolero

Well-Known Member
Range rods - yep. I haven't worried much about this but have a friend with range rods and he
has checked a few guns. All were OK.

Throat diam and thread choke are the big boogers in revolvers.

Bill
 

popper

Well-Known Member
Was comparing a LCR & SW at the LGS the other day, trigger pull on the SW was terrible and cylinder was a tad loose when I, assume, it should be locked.
 

Pistolero

Well-Known Member
No. But that is a common, yet erroneous assumption.

Cylinder locked is BAD news. This is the root of Colt's "won't hold timing for long" problem. Colt's have
the hand pushing up and the bolt holding solid so the cylinder is locked solid at firing. Seems wonderful, and works
fine if every cylinder hole lines up perfectly with the bore at that moment. The trouble is that they don't. So that
bullet will NOT make a corner as it exits the cylinder, but it WILL hammer the heck out of the hand at each shot as
it lines the cylinder up. Highly variable effect due to variations in how accurately the cyl bolt slots are cut relative
to the cylinder holes. When all are very close, timing is good for a long time. One or two off....timing does not
last as long.

S&W, OTOH, has a touch of slop. So, the bullet pushes the cylinder over a little right or left as needed and the bullet
goes on it's merry way, no harm to the innards. Way better, and this is why Smith's hold timing for years and year
and years, pretty much forever, actually.

Back to quick inspection.....take your good light and a set of appropriate gauge pins. .38 Spl and .357 should take
a .357 or 358 pin in the front of the cylinder if it is properly clean. Crud can defeat this, needs to be clean. A
.44 should have .430 throats, +/- 0.001, ideally. A .45 cal should have .452 or .453 throats, ideally. A couple thousandths
larger can be dealt with with larger bullets, but much more than .359 or .432 or .454 and you are going to have some
trouble getting best accy from the gun. Too small is easily fixed by reaming and polishing to your ideal dimension.

Look for an evenly cut, smooth forcing cone.

Bill
 
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