Ruger MK III Sights

LBussy · March 27, 2018, 07:13 AM

I have a Ruger MK III, I think it has a 4-3/4" barrel. The rear sight is in a dovetail and the front sight looks as if it's a ring wrapped around the barrel end. There's no discernible adjustment on the front sight.

In order to "shoot straight" I've had to drift the rear sight over quite a bit ... like to the practical limit in the dovetail. If I had to guess, I'd guess the front sight is not on straight but since I can't move it I can't really check that.

Has anyone seen this before or have a clue why it seems so "off?" Other than this it's a fine shooter, groups are right where I'd expect them to be.

Mobuck · March 27, 2018, 07:37 AM

There was recent post on rugerforum about an off-center front sight on one of these pistols. IIRC the front sight blade may be pinned into the boss vs dovetailed so no adjustment. You might secure the barrel in a padded vise and carefully(not using the grip for a lever) check to see if the barrel is unscrewing itself from the receiver.
FWIw, Ruger will likely resolve the problem if you contact them.

LBussy · March 27, 2018, 07:54 AM

I had no idea the barrel was screwed into the receiver ... for some reason I thought they were a single piece. Makes sense though.

T. O'Heir · March 27, 2018, 02:45 PM

You sure that's a Mk III? Looks more like a Mk I or II. Mk III front sights have a screw holding 'em on. Your's appears to have the pin found in Mk I & II pistols.
Anyway, manuals for all of 'em are here. http://stevespages.com/page7b.htm
There are exploded drawings in the Manuals, but the I and II drawing are here.
http://stevespages.com/page7a.htm
You won't be moving a Ruger barrel in a padded vise. I'd be suspecting that front sight blade is bent. Check that first.

LBussy · March 27, 2018, 03:14 PM

Quote:

Originally Posted by T. O'Heir

You sure that's a Mk III? Looks more like a Mk I or II. Mk III front sights have a screw holding 'em on. Your's appears to have the pin found in Mk I & II pistols.
Anyway, manuals for all of 'em are here. http://stevespages.com/page7b.htm
There are exploded drawings in the Manuals, but the I and II drawing are here.
http://stevespages.com/page7a.htm
You won't be moving a Ruger barrel in a padded vise. I'd be suspecting that front sight blade is bent. Check that first.

Definitely a MKIII, says so on the receiver. Definitely has a pinned front sight too.

The blade might be bent, but if so it's been bent a really long time. The original owner (who could be lying but he seemed like an honest older gentleman) said it had "shot right" since he bought it.

**4V50 Gary** · March 27, 2018, 04:33 PM

Check alignment of barrel and receiver. Can it be offset?

LBussy · March 27, 2018, 05:52 PM

Quote:

Originally Posted by 4V50 Gary

Check alignment of barrel and receiver. Can it be offset?

I don’t know. Can it? Not sure how one would check that.

SGW Gunsmith · June 9, 2018, 10:43 AM

Definitely a Ruger Mark III. You can tell by the right end of the magazine release just in front of the right side grip panel. Concerning sights.

Being a Ruger Mark III, isn't the receiver drilled and tapped for an optics base? A red-dot would eliminate any crooked sight condition.

Scorch · June 10, 2018, 01:40 AM

It's actually a fairly common problem with the 4" fixed sight models. I have seen it for years, and my old Mark I had the same issue. You can live with it or go to the hassle of indexing the barrel, which sometimes causes them to become jam-o-matics.

zukiphile · June 17, 2018, 09:23 AM

Quote:

Originally Posted by LBussy

Other than this it's a fine shooter, groups are right where I'd expect them to be.

I've had Ruger fixed sight centerfire pistols that required the rear to be drifted well off center. It doesn't look right if you focus on it, but after a while I forget about it.

If you "fix" this, will it make the pistol any better, or risk making it worse in a way that matters?

If you don't mind my asking, what sorts of groups are you getting? I sold my last MKII, a 6 and 7/8 inch barrel, in the 90s and recently bought one with the short barrel, a 50th Anniversary model. I look forward to picking it up next week.

zukiphile · June 21, 2018, 12:15 PM

..

SGW Gunsmith · June 22, 2018, 01:16 AM

No, I don't know where you get that information about that being a common problem, but it's way off base and not anywhere near the truth!

March 27, 2018, 07:54 AM	#3
LBussy Senior Member Join Date: February 26, 2012 Location: Kansas City, MO Posts: 296	I had no idea the barrel was screwed into the receiver ... for some reason I thought they were a single piece. Makes sense though. __________________ -- Lee Bad decisions make good stories.

March 27, 2018, 02:45 PM	#4
T. O'Heir Senior Member Join Date: February 13, 2002 Location: Canada Posts: 12,453	You sure that's a Mk III? Looks more like a Mk I or II. Mk III front sights have a screw holding 'em on. Your's appears to have the pin found in Mk I & II pistols. Anyway, manuals for all of 'em are here. http://stevespages.com/page7b.htm There are exploded drawings in the Manuals, but the I and II drawing are here. http://stevespages.com/page7a.htm You won't be moving a Ruger barrel in a padded vise. I'd be suspecting that front sight blade is bent. Check that first. __________________ Spelling and grammar count!

March 27, 2018, 04:33 PM	#6
4V50 Gary Staff Join Date: November 2, 1998 Location: Colorado Posts: 21,832	Check alignment of barrel and receiver. Can it be offset? __________________ Vigilantibus et non dormientibus jura subveniunt. *Molon Labe!*

June 10, 2018, 01:40 AM	#9
Scorch Senior Member Join Date: February 13, 2006 Location: Washington state Posts: 15,248	It's actually a fairly common problem with the 4" fixed sight models. I have seen it for years, and my old Mark I had the same issue. You can live with it or go to the hassle of indexing the barrel, which sometimes causes them to become jam-o-matics. __________________ Never try to educate someone who resists knowledge at all costs. But what do I know? Summit Arms Services

June 21, 2018, 12:15 PM	#11
zukiphile Senior Member Join Date: December 13, 2005 Posts: 4,450	.. __________________ http://www.npboards.com/index.php Last edited by zukiphile; June 21, 2018 at 08:58 PM.

March 27, 2018, 07:37 AM	#2
Mobuck Junior member Join Date: February 2, 2010 Posts: 6,846	There was recent post on rugerforum about an off-center front sight on one of these pistols. IIRC the front sight blade may be pinned into the boss vs dovetailed so no adjustment. You might secure the barrel in a padded vise and carefully(not using the grip for a lever) check to see if the barrel is unscrewing itself from the receiver. FWIw, Ruger will likely resolve the problem if you contact them.

June 9, 2018, 10:43 AM	#8
SGW Gunsmith Junior member Join Date: December 31, 2014 Location: Northwest Wisconsin Posts: 285	Definitely a Ruger Mark III. You can tell by the right end of the magazine release just in front of the right side grip panel. Concerning sights. Being a Ruger Mark III, isn't the receiver drilled and tapped for an optics base? A red-dot would eliminate any crooked sight condition.

June 22, 2018, 01:16 AM	#12
SGW Gunsmith Junior member Join Date: December 31, 2014 Location: Northwest Wisconsin Posts: 285	No, I don't know where you get that information about that being a common problem, but it's way off base and not anywhere near the truth!