Did Ruger manufacture MK678G pistols in MkII and MkIII?

[rustymusket]

I saw and put a hold on a used Ruger MK678G pistol from an estate sale, although the executor cannot find any magazines for it. The price is low, the condition is great, and I've been told they will hold it for me for a few more days to obtain magazines for it.
In attempting to purchase replacement magazines at a local gun show today, I've discovered Ruger manufactured a magazine for the MKII pistol as well as a magazine which fits the MKIII and MKIV pistols.
What 'identifiers' should I be looking for on this pistol as being either a MKII or MKIII model?
Someone at the gun show said the magazine releases were different, but couldn't tell me what any of the differences are.
Also, does this pistol give best accuracy with standard velocity ammo (as does my S&W M-41) or with HV ammo? I usually shoot bullseye at 25 yds.
Thanks, Rusty Musket

 

[hittman]

The gun will have MKII or MKIII roll marked on it.
Also, I think but am not sure, the MKIII had a loaded chamber indicator.
If it is truly a "G" gun I believe Government Competition Target (or Model?) will also be roll marked on the gun.
Magazines are very common and plentiful and inexpensive. Any local sporting goods store should have some.
Mine shoots fine with basic Federal bulk ammo but, I don't shoot competition, only plinking.

 

[rustymusket]

Hittman:
Thank you for the valuable information. I am away from where the pistol is but will be going there this afternoon to inspect the pistol for any identification of the model as a MkII or MkIII. I do recall it bearing the identification of "Government Target" and will then head over to the gun show and grab some magazines.
Things are falling into place and I am very excited to buy the pistol and detail-strip it to give it a good cleaning and inspection, although the previous owner appears to have cleaned and oiled it after the last use.
Rusty Musket

 

[shootinfule]

My MKII 678G has "Mark II Target" on the left side of the receiver. The right side of the receiver is marked "Government Target Model". As stated above it takes the standard magazines with the release at the bottom of the grip. Mine prefers standard velocity 22s. It is a very nice shooter.

 

[lipofsky]

if it is a MK III, MK II magazines will not work due to the magazine safety.
If it is a MK II then th MK III magazines and the MK II magazines will work in a MK II gun.

 

[Highstandardguy]

The answer to your question is yes, but they made very few of the MKIII version. If you got you're in tall cotton.

 

[chet15]

The answer to your question is yes, but they made very few of the MKIII version. If you got you're in tall cotton.

#1
Correct...they didn't make very many. I don't believe the blue Government model was ever cataloged, but they do exist in the 227-04601 to 227-04698 and 227-06915 to 227-06937 serial number blocks, so there may be as few as 121 of those.
I'm thinking Ruger used up their left over MK678G barrel stock.
If you do have a MKIII678G be sure to send me a PM with the serial number so I can add it to my list of the few that are known.
Chet15

 

[SGW Gunsmith]

I saw and put a hold on a used Ruger MK678G pistol from an estate sale, although the executor cannot find any magazines for it. The price is low, the condition is great, and I've been told they will hold it for me for a few more days to obtain magazines for it.
In attempting to purchase replacement magazines at a local gun show today, I've discovered Ruger manufactured a magazine for the MKII pistol as well as a magazine which fits the MKIII and MKIV pistols.
What 'identifiers' should I be looking for on this pistol as being either a MKII or MKIII model?
Someone at the gun show said the magazine releases were different, but couldn't tell me what any of the differences are.
Also, does this pistol give best accuracy with standard velocity ammo (as does my S&W M-41) or with HV ammo? I usually shoot bullseye at 25 yds.
Thanks, Rusty Musket

Mark II magazines are smooth along both sides of the magazine body, no bumps or protrusions. The Ruger Mark III magazines have two protrusions, the one on the left side is for the trigger fin on the Mark III pistols to make sure the magazine is seated properly, due to the magazine disco parts. The protrusion on the right side of the magazine is for the magazine latch/release. Costs run about the same for new magazines.

 

[1gunsnotenough]

I had a KMIII678G a couple of years ago. But did not fit in with my Mark II collection. So sold it but kinda regret selling.

 

[chet15]

Not sure why Ruger doesn't bring a 678G variant back out in the MKIV. The MKII sold by the tens of thousands.
Chet15

 

[22/45 Fan]

If the gun is a MkII, it will have the magazine release at the base of the grip, i.e. a "heel" release. If it is a MkIII, the magazine release will be a push button on the left side behind the trigger guard like a 1911. Magazines for either are plentiful.

CDNN has MkII magazines: https://www.cdnnsports.com/mkii-22-10rd-ruger-fact.html?___SID=U#.WX5g8NMrI3g
Everyone has MkIII/MkIV magazines.